Aquarium Information Bureau GmbH

Sound biological advice for the curious fishkeeper ... with an upcoming illustrated volume in the works

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There are some highly remarkable plants available to freshwater aquarists, some bizarre things that live in the water, and some bizarre living things that are also beautiful. Meet Neptunia oleracea - the water mimosa or water sensitive plant, also known as the sensitive neptunia - which is ideed one of the sensitive plants, that respond to touch as though they were an animal. This trait is known as seismonasty, and it is common (but not universally present) among the clade of plants called the mimosoids, and it evolved either as a defence against herbivores, or maybe to avoid potential leaf damage from raindrops in regions with rainy climates. Another particular terrestrial plant with this habit (Mimosa pudica) is appreciated by indoor gardeners as a novelty houseplants, as are unrelated touch sensitive plants, most of which ae carnivores, which mimosoids are not. However the non-carnivorous and seismonastic N. oleracea is much more obscure to green fingered aquarists, even though its tender stems, young leaves, and shoot tips are all eaten in vegetable, dishes, and parts of the same plant are further consumed for their medicinal properties.

Even the origins of N. oleracea were long considered to be shrouded in some degree of mystery. Currently the plant has quite a pantropical distribution, although it was first described using a plant from Vietnam. The very closest relatives of N. oleracea are indigenous to the Americas, therefore confirming their origin is also located in the western hemisphere. Some populations of this plant are known to have been naturalised recently, for instance, in the USA and Australia. Yet I cannot help but remember the mystery that the famous terrestrial sensitive plan (M. pudica) - which is likewise known to be of South American origins, and has similarly become widespread now in warm countries of the world - has names in Sanskrit, which has been interpreted to indicate a very early introduction. There is still a question mark over the distribution and history of these curious plants. Unlike some other plants implicated in the notorious 'before Columbus' genre of theories, I am not aware of any history of these plants, citing appropriately old sources, potentially verifying or strongly indicating their antiquity (or otherwise) in Asia or elsewhere; a Portuguese source demonstrates that M. pudica was entrenched in South Asian herbalism, by the late 16th century - late enough to be post-Columbian, sure, but by what route? Although most such suggestions have long since been disproved, or at least weakened, there are still mysteries about the dispersal and local antiquity of some plants.

When in the wild, N. oleracea is primarily found growing prostrate in wet, waterlogged soils beside the water's edge, in which situation it grows a long, deep taproot; or of more interest to the aquarist, floating on the water in still or slowly flowing freshwaters, that are up to 80 centimeters deep. The latter feat is possible because the floating stems possess a white and spongy air-conducting tissue that keeps them afloat, and that is appropriately absent in those stems growing on land. These plants grow to 6 inches or 15 centimeters tall, but they possess a creeping habit: their floating, aquatic stems may reach even 60 inches or 150 centibeters or thereabouts. Even the roots of this plant are of interest to the botanist; for like related plants, N. oleracea uses its roots to accommodate and employ symbiotic bacteria that fix nitrogen. But unusually it does not develop the expected root hairs, and instead develops nitrogen-fixing nodules at the emergence of lateral roots on the primary root, and on the adventitious roots emerging at the nodes that grow along its floating stems.

Although N. oleracea is a rare plant in home aquaria, it is considered eyecatching for its delicate foliage, which is respected as pretty, just as it is noteworthy for its behavior. For although its leaves look typical for a mimosoid, their appearence is exceptional for an aquarium plant species. Fortunately for the admiring aquarist, this species grows well in open top freshwater aquariums, as well as in paludariums and indoor ponds, as long as the plant recieves sufficient light and warmth as it would in the wild, since it mostly grows in tropical and subtropical climates, and in no more than light shade. Per expert opinion, the ambient temperture for this curiosity ought to be at least 21 degrees centigrade, making them appropriate for tropical aquariums. Where they grow wild the pH of the water may be anywhere from about 5.5 to almost 8, but they tolerate neither dryness nor brackishness. Given the correct environment it can grow quite rapidly, and fast enough, in fact, to choke inland waterways. In all this floating plant has a history of positive and negative implications for man, of which the ornamental planted aquarium is but a minor part.

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Most of the freshwater fishes in our aquariums are either catfishes, carps, characins, or perches such as cichlids and toothcarps. However there are more unusual fishes either regularly or sporadically encountered in the aquarium trade; the herrings are not usually among them, and fer herrings are freshwater fish. So there are reasons why Denticeps clupeoides, the denticle herring from West Africa, is worthy of zoological commentary. The denticle herring is distinguished from other herimgs by the remarkable presence of its namesake denticles - these being numerous small teeth on the surface of its head. These structures truly are teeth and do not merely bear a resemblance to teeth, and they resemble the oral teeth of the animal in their shape and size, although they are not used by the fish in biting. Some other true fishes also possess teeth outside of their mouths, but it is an exceptional characteristic nonetheless. Despite being found only in rivers, it is a true herring, and it is also an ancient offshoot of the other modern herrings that retains certain ancient traits that would have been present in ancestral herrings. Despite all of these points of interest, D. clupeoides is an unassuming size, no longer than 15 centimeters or 6 inches, and not usually longer than around 8 centimeters or 3 inches, and it is not visually dazzling.

Although only D. clupeoides is recognised today, the denticle herrings as an evolutionary line are ancient sisters to all other modern herrings, called the clupeoid herrings, which include the anchovies, sprats, shads, pilchards, and sardinellas - all varieties of herring. Although we usually think of herrings as marine fishes, the clupeoid herrings have colonised rivers more than once around the world, over the course of their evolution. The modern denticle herring almost certainly descends from a marine ancestor that colonised up freshwater rivers; there are no denticle herrings recognised among the fossil record of any continent excepting Africa. In all this little African fish is to the herrings, what the Australasian monotremes are to mammals; what the Asian tarsier is to the monkeys; and what the New Zealand tuatara is to lizards. It is not that Denticeps is unchanged from a known ancient ancestor - it is not truly a 'living fossil'; but that it is a phylogenetic outsider among its evolutionary line, one that has some ancient traits its relatives have modified or lost, during the same geological timescale since their ancient ancestor.

The denticle herring is indigenous to the lowland rivers of the Guinean region of Africa, such as the Oueme and the Mungo. It forms schoals in the midstream of the river, where the current is strong. This oxygen demand makes the denticle herring difficult to transport, and they need good oxygen levels and water flow if they are to survive and thrive in the aquarium. Once in the aquarium they are peaceful to other fishes and apt to cohabit with other species. Denticle herring possess numerous pointed and conical teeth suited to siezing small arthropod prey, as well as some gill rakers appropriate for filter feeding behaviors. In the aquarium they are observed to be unfussy feeders, although they are observed to be reluctant to feed from the bottom of the aquarium. This means that dentical herrings should share aquarium space well with bottom swimming fish like catfishes and loaches. Naturally they should be accommodated with numbers of conspecifics, and as they are active, powerful swimmers, they require much unobstructed swimming space. In addition to their requirement for space. and for high oxygen levels and water flow, these riverine herrings like soft water with a pH that is between around 6 and 7, and a temperature between 25 and 29 degrees, based on the water parameters of their habitats of origin.

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Today I saw some peninsula newts advertised for the aquarium; they are a regional race (named Notophthalmus viridescens piaropicola) of the more widespread red spotted newt, which was formerly more widely availabl to aquarists and exotic pet fanciers. Specifically they are natives of peninsular Florida, and are thus the southernmost populationss amid a wider distribution of N. viridescens as an entire species. Over the wide range of the species, it is noted that the southerly populations have a genetic disposition, to function at higher tempertures than those further north; and it is noted that the southern populations are active and feed all year round, athough with slower digestive passage in cooler temperatures such as 5 to 6 degrees centigrade. It is also worth pointing out that in all populations of N. viridescens, the adult newts are commonest in shallow water, in sunny areas; these newts remain just below the thermocline in the hottest weeks, to evade strong heat. N. viridescens is quite a habitat generalist: they are found in natural ponds and wetlands, and in slow flowing streams, as well as anthropogenic freshwater environments such as canals and ditches. However they are well associated with submerged and emergent macrophytes, and they are averse to fast flowing waters.

Like all other American newts the adults are amphibious and capable of migration between ponds. They will leave ponds to avoid desiccation and heat stress in hot weather, and if living terrestrially their skin cornifies and becomes more glandular, whilst the finnage of the tail decreases. Their behavior when out of the water is to hide amid forest debris and vegetation clumps; they are not in the least fossorial. Of course, the spawning and pre-metamorphic growth of these newts is entirely aquatic, and in ponds which the adults have vacated, the young metaporphose at larger sizes. Upon metamorphosis, N. viridescens famously disperses by an 'eft' (newly metamorphosed juvenile) stage on humid nights; although this is common in some populations and is not seen at all in others. At this time the dispersing efts start to behave as do adults when they are on the land, at which times efts are active above 12 degrees centigrade. (Originally the word 'eft' simply meant a newt in English, though the etymology of this word is actually unknown; the words 'eft' and 'newt' appear to both derive from 'ewte, efete, efeta'. The word 'eft' has since semantically divorced to ro refer to a terrestrial, juvenile life stage that is present in the American newts.)

Peninsula newts are noteworthy for being particularly tied to water, for example in lacking the juvenile eft stage and remaining aquatic; though it is not really remarkable for N. viridiscens living in securely permanent habitats to skip it altogether, because it is merely triggered - like adult dispersals over land - by environmental circumstances forcing unusual habitat use. (Given that adult newts living on land assume eft-like phenotypic traits, and that efts are defined by their metamorphosed status, I personaly consider the concept of an eft as a physically distinct life stage which may be skipped, to be a category error: it is simply that post-metamorphic N. viridescens can cross over land, and adopt appropriate physical traits as they do so.) Adult peninsula newts have been identified on land but this is rare because ot occurs in atypical situations. However they are more commonly found clambering out of the water, upon the floating water hyacinth plants which were was introduced into the range of the peninsula newt during the 1880s. Befitting of an aquatic salamander, sexually mature peninsula newts tend also to possess at a relatively frequent tendency, certain neotenic physical traits, although these tend to be more limited in Notophthalmus than in, for example, the mole salamanders belonging to the genus Ambystoma.

Different N. viridiscens populations may vary as to the environmental conditions, such as pH, that their physiologies are optimised to. However the species as a whole are more likely to remain aquatic in ponds with a more circumneutral pH (above 6) than those with a lower pH of a little above 4. Peninsula newts are sympatric with lesser sirens which prefer a pH between 5 and 6.5, therefore I might suggest peninsula newts to prefer soft and slightly acid parameters. Peninsula newts should do fine in an unheated room temperature tank (that is, 18-22 degrees centigrade), but due to their Floridan origins they are active underwater where tempertures are as high as 26 degrees in the wild. Generally their care and compatibility is as for other newts from ponds and ditches: they are gape limited carnivores that grow 10 to 14 centimeters long, or between about 4 and (rarely) above 6 inches. In my experience, non-breeding adult newts cohabit very well with non-breeding fishes, although some of the latter can nip the gills of neotonic adults, which is not a concern for all peninsula newts. Newts detect foods by chemosensory cues that travel through water easily, so they readily accept defrosted foods and dried preparations, of a suitable nutritional content and size, from the substrate. As many fish are faster swimmers, the newts might not recieve enough foods, if greedy fish take it all first.

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Some people are fascinated by the very ancient animals called triops, tadpole shrimp, or shield shrimp. A part of their appeal is their unusual appearance; another is their reputation as an ancient life form, sometimes confused with extinct trilobites; and yet another is their annual life cycle, which allows these arthropods to be commodified in the form of 'kits'. Needless to say, triopids do require proper care, as do all other organisms. In Europe at least the 'go to' species in culture is Triops cancriformis, the European tadpole shrimp - though there may well be grounds to interpret T. cancriformis as a species complex. Indeed to Europeans, T. cancriformis tends to be the animal held reflexively in mind when talking about Triops. T. cancriformis is indigenous to Europe and adjacent areas as far away as India - but who kbows what the taxonomic future will hold. Large T. cancriformis may exceed 10 centimeters, of 4 inches, in length, although around half of this length is a more normal size. Admittedly these animals are fascinating to enjoy as pets, and they are also to learn about as miracles of evolution in their own right.

Triops sp. are classified into several species but the individual animals are variable, making their species identity difficult to discern. Together with their evolutionary conservatism or stasis, their morphological variability has also made the fossil tadpole shrimp difficult to interpret phylogenetically. However one chooses to interpretthe fossils, animals that are definitely tadpole shrimp are as ancient as the Fammenian stage of the Devonian, although they were not quite of a modern aspect. Thus in fact they are not as ancient as land plants, or insects, or scorpions; nor are they as ancient as four footed vertebrates. However in all the time that passed since the Fammenian, tadpole shrimp have differed from their ancestors much less, a phenomenon described as evolutionary stasis. It is a bit mysterious as to how tadpole shrimp arrived in their freshwater pools back then: but today their tiny, lightweight, resilient eggs are knowny be transported by the wind, by the actions of larger animals (such as humans or birds), or by the runoff caused by rainfall - all possibilities whilst they are still fertile but dormant and known as cysts. Today human activities have transported members of certain Triops populations far from their original places of origin, and usually inadvertently.

Despite their obvious similarity to the horseshoe crabs, Triops sp. are in fact more closely related to insects, and even moreso to the much smaller brine shrimp and daphnia. It is the kinship to insects that places the tadpole shrimp and its smaller relatives outside of the true crustaceans; thus these animals are only 'shrimp' in the same, allusory way that daphnia are 'water fleas'. (However, they were historically considered as crustacean fauna, nd they are still studied by crustaceologists rather than insect-focused entomologists.) Properly the insect-related group as a whole are called the atelocerates, whereas a grouping named tetraconates has substituted for the old use of crustacea by zoologists; the shift was neccessary because insects - by definition - cannot be crustacean arthropods. Too often the name 'Pancrustacea' is preferred for the tetraconates, and I admit that it has rather stuck: however it properly implies the total group of crustaceans, which must therefore - by definition - exclude the insects, and therefore the other atelocerates.

Triops sp. are dwellers of short lived freshwater pools, and accordingly they have short lives themselves. Dying en masse when the water recedes, their population persists as fertile eggs deposited on the bottom. These are resistant to drying out and other extremes of the envronment, prior to the seasonal refilling of the pool by the return of benevolent weather. Young Triops sp. are in fact averse to extremes of pH, and the larvae should not be exposed to a pH below 6; similarly they do not survive to complete their life cycle where the pH is above 9, and the occurrences of adult Triops sp. in alkaline freshwater environments, can be explained by relatively lower pH values at the time of inundation. The average pH where wild T. cancriformis was found, was a little above 7, and the temperture was compatible with an unheated living room. Naturally they will not suffer the drying of their homes in captivity, but natural selection did not grant them long lives: Triops sp. generally live for about 20–90 days in the aquarium, or if they are fortunate and their temporary pool habitat does not dry up in the wild.

All of the species of Triops are similar, and not least in their feeding habits: all of them happen to be omnivorous by niche, with tastes for biofilms and organic detritus, as well as impulses towards preying on smaller animals. Whilst the feeding apparatus of triopids is competent for tearing at materials such as plant roots or carrion, they cannot handle struggling prey a similar size to themselves. Therefore although these animals are cannibals, similarly sized individuals may be housed together with conspecifics, and likewise with the members of other Triops species. Although people often ask wether Triops may be housed together with sea monkeys (Artemia sp.) from the same kinds of habitats, the answer is no. In the aquarium, Triops sp. are fed such items as carrots and dried shrimp, so they are not really very fussy animals as to what they consume as nourishments. However they are strongly biased towards foraging from the substrate, rather than suspension feeding up above.

Due to their short, annual lifespan, Triops sp. are best cultured over generations from their eggs. Common pet tadpole shrimp like T. cancriformis, and the American T. longicaudatus, are generally self-fertilizing hermaphrodites. In fact T. cancriformis is so variable that some populations of this species require two sexes to breed, whereas others do not. Whereas in the Asian species T. granarius, two sexes are required. I should reiterate that it is not always clear which populations belong to which species, and it is speculative which naturally ocurring morphs are truly different Triops species. Also due to their size, 'pet appeal', and ease of culture, Triops have now been bred into ornamental color morphs - domesticated strains of some Triops species, that do not exist in the wild. Some other tadpole shrimp species that are traded as pets, such as the western hemisphere T. newberryi and the antipodean T. australiensis, require warmer aquarium water (such as 30 degrees centigrade - not below 25 and not as high as 34 degrees) although their care is broadly identical otherwise, such as a preference for circumneutral water chemistry.

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Sometimes I am asked questions about the care of the tropical lizards called basilisks. There are in fact a number of basilisk species, although not all of them are common in the exotic pet trade. One typical species might be the common basilisk of Central America, Basiliscus basiliscus. This species grows up to 75 cm or 30 inches long, of which the tail is responsible for up to 3/4 of its total length. The males of B. basiliscus are the larger sex per length and mass, and they possess more prominent dorsal and cranial crests. The snout to vent (or head and body) length of the adult male basilisk is between 1/5 and a 1/4 longer than that of the aduly female. However the degree of sexual dimorphism observable is greater in the species B. plumifrons and B. vittatus, than in B. basiliscus. Basilisks stereotypically inhabit tropical forest beside ponds, streams, rivers, sinkholes and sometimes even the sea; however, at least two basilisk species, B. plumifrons and B. vittatus, may also be found in forest far from the water, so some species of basilisk are more generalist than are others. B. basiliscus is found in suitable habitats of Central America, from Mexico to Panama, and into the north of Colombia and Venezuela. All of the basilisks are in fact found in Central America and the northernmost part of South America; surprisingly, they are not present as far south as Amazonia.

The same is true of the extant lizards that are the closest relatives of the basolisks, and with which they form a clade of climbing lizards, called the corytophanids (the helmeted or casqued lizards). Curiously, several fossil corytophanids are known today from localities in Europe and North America, where they thrivved during a time when the climates of these continents were warmer. The present distribution of corytophanids is suggestive that they colonised South America late and during a faunal interchange of animals between North and South America. Although they went extinct in the northern faunal realms, their range into tropical South America appears rather marginal. Basilisks stand out among other lizards, because they are visually regognizable by their contours. The notable bony head crests of corytophanids are formed by the bones pf their cranial vaults, and they first evolved as attachment points for the inserion of muscles that are associated with biting. In basilisks, the male of the species grows a lighter expansion of the crest, that happens to play no role in increasing their bite force. Similarly striking to the observer, are the tall, dorsal structures that are supported by long, slender neural spines rising from atop their backbones, thus forming elegant and remarkable sails crowninp their torsos and tails. Similar sails are seen in some other lizards today, and also in some extinct animals.

The basilisks are renowned for their amazing ability to run bipedally at the water surface, a habit that has earned them (and especially B. basiliscus) the name of Jesus Christ lizard. Although this ability is not exactly unique to the basilisks in the animal kingdom, it is an exceptional talent that is reminiscent of a miracle. When it is running along the water surface, the basilisk is dealing with the surface tension of a yielding, liquid surface; this is something difficult because it is unstable, and without a special running technique, the lizard would naturally sink towards its feet. The feet of a basilisk are large and their long toes are flanged at their sides with rectangular flaps of skin. These outgrowths trap air bubbles when the basilisk slaps down its foot fast, generating briefly an air filled pocket that displaces the surface water long enough to bear its weight, as the lizard pushes its foot back against the air pocket for forwards thrust; the foot must be retracted from the water fast, before the air cavity collapses. The flaps of skin maximise the surface area that is available upon contact between the feet and the water surface, and it is important that the water surface be disrupted as minimally as possible.

In the water, juvenile basilisks swim by side to side oscillations, assisted by frog kicks. Though the dorsal crests or sails of basilisks may look like the fins of a fish, they are anatomically quite different and actually make these lizards less efficient in the water, because they make their bodies more rigid than are those of most other lizards. Thus basilisks perform a frog kick to compensate and to make good use of their intermembral disparity once they are in the water. Basilisks are slow runners, but they are agile, and their dependence upon their hindlimbs is good for extra thrust during climbing or when traversing uneven ground. Basilisks prefer to run on the water towards the safety of an item such as a floating water hyacinth, than to dive neneath the surface, although they are recorded to dive at least as deep as 3 and a 1/2 meters down. Typically basilisks are thought of as arboreal lizards that enter the water only to escape predators, but their gut contents demonstrate that some aquatic hunting occurs as an individual habit. Basilisks can be reluctant to take to the water for wariness of dangers from aquatic predators. Big, carnivorous fishes are known to attack them as they traverse the water surface. Amphibious foraging by the basilisks appears concentrated in the safety of shallow streams.

Basilisks can be skittish and injure themselves by darting off, at which point they hit themselves on the sides and especially the glass. Not all of them are, and in fact captive bred and long term captive animals may be quite tame; in which case they are regarded as a good pet lizard. Because spooked basilisks may be prone to dart off recklessly, skittish aquisitions should be housed in a large vivarium, and a room sized vivarium might well be optimal for this reason; it is also the best for accommodating a breeding colony. The minimal acceptable terrarium footprint for a calm basilisk, is said to be 2 and a 1/2 times its total length in both directions. But it matters that the juveniles will use the floor space more than will the adults, which is because they grow increasingly arboreal with age. Adult basilisks, especially, need height to climb more than they require floor space. Male adult basilisks will fight between themselves, but the females will share if the environment is sufficient for them spatially. Each lizard will need at least a fifth more floor space additiona to that for just one lizard. Whereas zoos regularly cohabit basilisks with other lizards, and with turtles, fish, stingrays, birds, and mammals. They will however eat what fits into their mouths, rarely including such prey as rodents and snakes, so care may ne taken as to the size of the other animals within their exhibit. Basilisks may be cannibalistic, so this same caveat must apply to keeping them with one another. Wild basilisks willingly share foraging sites and beaches with other species, and they will even climb onto large mammals to consume insects there.

The dietary habits of basilisks are well known but what they are willing to eat can be personal: some captive basilisks refuse to eat items that will not move, and some of them refuse to eat plant materials such as fruit. Purposeful plant consumption is limited to large individuals, and predation on fish, frogs, squamates, and mammals is only opportunistic: their primary food source throughout life is arthropods, both terrestrial and aquatic, but they do not dig for prey. As a result basilisks consume more winged insects than they do larvae. Adult basilisks possess a stronger bite force than do the juveniles, which are less likely than the adults to consume slow or stationery items, although they have been observed to scavenge after crabs that were feeding on barnacles, but they do not consume cracked eggs although they attract insects that the juvenile basilisk eats. The juvenile basilisks forage more on the ground than do the adults, and out in the open among grasses, or on the beach. Thus the juvenile basilisks are ecologically different in their habits than the adults. In principle basilisks should consume nonmoving items, though even when they are mature and more omnivorous, their diet should remain dominated by lean animal protein.

By their nature, the basilisks are heliothermic baskers and behavioral thermoregulators, so a heat lamp and UV source is ideal; however in reality heliotherms are really getting warm by conduction from substrates heated by the sun. Basilisks take care to avoid the sun when substrates are the hottest: they bask at tempertures of 26 to 33 degrees centigrade, function best at 35 degrees centigrade, and avoid tempertures of 38 degrees or above. The humidity ought to befit a rainforest biome, perhaps 75 to 90 percent, although it can fall lower without ill effect; and if in doubt the reptile owner should have more concertn that the terrarium is ventilated well. (This is because stagnant air is far more dangerous to reptiles, than is lowered air humidity.) They need an opportunity to climb, and in the wild they can be found in trees as high as twenty meters above the ground level, and they also climb onto river rocks. Even the toe fronges that the basilisk uses to run on the water, first evolved in the trees because they are shared by other corytophanids too. The relative stiffness of the basilisk torso surely aids it when climbing, and the tendency towards reduced lateral mobility is also seen in unrelated climbing animals.

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Not many true fishes from temperate marine environments, are traded in fish stores, online or otherwise. But sometimes a popular public aquarium species, the Garibaldi (Hypsypops rubicundus) is encountered for sale, although it must not be kept in a tropical reef tank (because the optimum tempertures for a reef tank, re 27 to 29 degrees centigrade). This species may also be called the catalina goldfish on account of its coloration; the Garibaldi is not related to the goldfish, which is a carp, because it is the worlds largest damselfish - it grows up to 12 inches long, or 30 centimeters - and is therefore a perch. 'Catalina' refers to an island near California, and the Garibaldi has a range from California to Baja California, and nearby islands.

There this damsel inhabits shallow seas, were there are rocky bottoms, and especially rocky reefs on exposed to semi-protected coasts with clear water; the complex natural aquascape of the reef provides plenty cover for the Garibaldi to set up territories and hids. The species is less often associared with kelp, where it eats encrusting organisms on the kelp, and the juvenile Garibaldis are hardy enough to be found in intertidal rock pools. One of the oddities about the Garibaldi, is that the mature males are about 2.5 centimeters or 1 inch longer than the females. which is the opposite of what is normal in the damselfishes. The males guard the nests at which time they become famously pugnacious.

Besides the fact that the Garibaldi is not a tropical fish, its diet would make it unsafe in a coral reef. Their broad spectrum diet definitely includes anemones and gorgonians, and they are able to consume both branching and encrusting growth forms of sessile fodder. As omnivores they do consume red, green, and brown algae, with a preference for fleshier red kinds. Although their diet varies depending on variables, Garibaldi on average are thought to feed mostly on such macroalgae, anemones, annelids, and sponges; they also consume sessile and other benthic animals, including arthropods, molluscs and brittlestars. Such an animal is best categorised as a generalist and an omnivore, so they should not be problematic to feed in the home aquarium, although based on studies of wild Garibaldis, their diet should have a little more animal protein than vegetable matter.

In the aquarium, their aquascape ought to be one of complex rockwork, and it should provide them with suitable caves for retreats. This species, like other benthivorous damselfishes, is quite territorial, so only in large aquaria should members of this species usually be cohabited. They are not really a comunity fish for this same reason. Living in Monterrey Bay, in the north of Garibaldi distribution, the sea temperture is 12 to 16 degrees centigrade. However in late summertime, the fish from the southern end of their range, experience water tempertures of 21–24 degrees centigrade. Thus the Garibaldi can live without a chiller if the ambient room temperture does not exceed 24 degrees; it is reccommended that a habitable room in a house be maintained at 18 to 22 degrees, but heatwaves do occur, and purchasing a chiller is reccomended if the room temperture is not especially stable - but it would probably not need to be running all of the time.

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A lot of folklore exists about the aggressiveness of Epalzeorhynchos bicolor, a two-tone fish that is popularly traded as the red-tailed black shark, or similar names like 'red-tailed shark'. The name 'shark' is an abbreviated form of 'sharkminnow', a label applied to a number of fishes that are in fact carps. The name sharkminnow was first applied to carp (or barbs) of the genus Labeo, which has a rather fetchingly Jaws-like dorsal fin; however it is far too large to qualify as a minnow. In the past E. bicolor was thought to be a species within the genus Labeo; but it does not possess the same shaped dorsal fin. Nowadays some popular small cyprinids are called 'sharks' because they have are active swimmers with a streamlined appearence. Children and even adults are sometimes excited to have such a 'real shark' in their aquarium: "How big will it grow?"

However the main folklore in the aquarium hobby, relates to their supposed temperament towards other fish, when they are in the confines of the home aquarium. E. bicolor is often reputed to be more violent than it actually is, and sometimes it is even blamed for directly killing other fish, when it is seen nibbling on the body of an already deceased tankmate. Doubtless the name of 'shark' fuels such suspicions, although E. bicolor and its kin are not habitual carnivores, but grazers. Whilst it must be agreed that this animal, although it is not predatory, is definitely territorial and its actions may sometimes stress other fish, such exagerrations of aggression by 'sharks' distort its natural behavior. Most fish of this sort are not outright 'terrors' though their habits and habitus must naturally be considered.

There is some confusion as to the maximum size of E. bicolor; they typically grow to 13 centimeters, or over 5 inches, although some exceptional specimens have reached more like 20 centimeters or 8 inches. They have a black elongated body shape that is moderately compressed, and juveniles are more slender and streamlined than are adults. The female E. bicolor tends to become deeper and broader bodied than the male, but sex differences are harder to identify in young fish. E. bicolor is a fish of Mainland Southeast Asia, where it is still found in lowland streams, rivers, and creeks in the lower Mae Khlong, Chao Phraya, and Bangpakong river basins. Specifically they favor habitat with vegetation and large rocks, from which they rasp biofilms.

E. bicolor and its kin are evolved to feed on biofilms ('algae and aufwuchs') and detritus. Red-tailed black sharks have an underslung mouth that faces conveniently downwards, which is a trait of many bottom feeding fishes, as well as two pairs of barbels around it. Whereas the upper lip of E. bicolor carries a short, bristly ridge, the lower one bears a hard, scraping edge with which they can dislodge edible items from their hard substrates. In the aquarium they are not fussy eaters and accept foodstuffs of both animal and plant origins, but they do like an established aquarium, in which algae grows on the surface of rocks. Given the opportunity they are known to scavenge carrion, but despite their label as 'shark' - which is based on a superficial sleekness and a cruising habit - they do not kill tankmates to eat them. However they are famously territorial and some individuals are more aggressive than are others.

These are not fishes that appreciate companionship of their own or similar species, and can be very boisteros towards tankmates, with the most likely targets being other bottom dwelling fishes such as catfishes and loaches. However, I am convinced their supposed aggression is exaggerated by hobbyist folklore. Many people have housed them with disimilar species, and even bottom dwellers, without harm to the other fishes. It seems that although larger E. bicolor are more pushy, they are not so towards tankmates that became familiar to them whilst they were still small. In my experience E. bicolor rarely or never do physical harm, but their presence may be fatally stressful to fellow tankmates, unless the aquarium is large - though they are community fishes, they are not suitable for small community tanks. That and all other bottom dwellers must have access to an aqascape that facilitates their retreat.

In the wild, E. bicolor experiences environmental variables that change with the time of the year, because of the influence that is held by the monsoon over the climate of Southeast Asia. These fuish can tolerate a water temperture of 30 or 31 degrees centigrade in the summer months, but this drops to about 25 degrees in the cooler months. The pH is circumneutral but leans to the base side; in any case these fish are adaptable to any 'drinkable' water quality expected in an ordinary, freshwater aquarium. In the past E. bicolor was much more common in the wild than is the case today. Nowadays the species is so endangered in the wild, that it was recently feared extinct in nature. Fortunately captive breeding for the aquarium trade has saved its phylogenetc life, but its still sad that nearly a hundred years ago, this beautiful species was living even in the canals of Bangkok.

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Just as unrelated fishes are known as angelfishes and butterflyfishes, among other things, so too there are two kinds of batfishes encountered in the aquarium trade. The other batfishes, besides the deep bodied Platax sp. which are quite dissimilar, are actually squat and curiously shaped anglerfishes related to the frogfishes. In the trade it is possible, however rarely, to find these walking batfishes retailed; one such species is Ogocephalus cubifrons, the polka dot walking batfish. Sometimes it is known as O. radiatus, which is understood to be a junior synonym of O. radiatus; juvenile fishes are hard for even ichthyologists to distinguish from similarly aged O. cornutus, the longnosed walking batfish, with which it is sympatric.

O. cubifrons reportedly grows to 38 centimeters or 15 inches long: but specimens collected for the aquarium trade, are more typically 12 to 20 centimeters, or about 5 to 8 inches, which is not full grown. Such a maximum size as described must, however, be exceptional. This anglerfish is native to open sea bottoms in the shallow waters from North Carolina, southwards to Cuba and the Yucatan Peninsula. It is thus associated with the Caribbean Sea, and the Gulf of Mexico, and also the Bahamas. As it is found on rocky as well as soft seabed, it's habitat requirement appears to be a low relief seabed The reason these animals are not more often traded, is their poor survivability, which is due to unthoughtful practices during the time between the ocean and out tanks. Fortunately, advances in knowledge have been made by public aquariums, that help us understand why these fish have high mortality - and how to avoid this problem

Walking batfish are named for their amazing ability to walk, which is possible because their paired fins have evolved into bona fide walking limbs. As they move they keep their belly clear of the substrate, and employ a land vertebrate-type gait. Their pectoral fins and those of their close cousins, the frogfishes, have been well studied and compared to those of land vertebrates. Similarities include a ball and socket joint at the shoulder, an elbow, and something very like a wrist. The musculature is similarly modified to allow these joints to function as a true leg.

Batfishes and frogfishes are different in details of their forelimb anatomy, reflecting their lifestyle; frogfish forelimbs resemble toed feet in their ability to deal with complex substrates, whereas batfishes lack this skill but their walking strides are more powerful, as befits low relief, open habitats. The gaits of both frogfishes and batfishes have been compared to those of four footed land animals, although both types of anglerfishes are strictly submarine (Interestingly the limbs and even toed feet of ancestral four footed animals, are now thought to have evolved before the conquest of the land )

Although walking batfishes are gape limited suction predators, like their frogfish allies, they do not share the same cavernous maws, and take smaller prey items, as well as inhabiting different types of sea bottom. As expected for an anglerfish, batfishes entice victims close using twitches of a lure (or esca), which has evolved from their anterior dorsal fin rays. Anglerfishes actually twitch a fishing rod that belongs to their body. Unlike deep sea anglerfishes, walking batfishes do not have a glowing lure; but evidence indicates that they possess complex, glandular structures in their esca, that are used for secreting chemical attractants into the water.

They have been proven to lure in scavenging carnivores, such as dog whelks, as prey. Such small animals are often deliberately introduced to aquariums because they are helpful scavengers, or they enter aquaria accidentally but nonetheless are desirable and helpful. Walking batfish are obviously a danger to such 'janitors' and are plainly incompatible with, for example, the snails called nassas. However they do not consume corals in the least, and it would be wrong to think of these anglerfish as consuming tankmates nearly their own size. Their diet does, however, include crustaceans and small fishes, which again limits their compatibility in the reef tank.

In the aquarium walking batfishes have a poor survival rate upon import. The sad fact is that these fish often carry high parasite loads, to which they succumb when they arrive stressed by the process of their importation and acclimatization Other than this, they do not really deserve a reputation, as hard to care for in the aquarium. Public aquariums have obtained healthy specimens and kept them long term without difficulties; though they have found a good de-worming to be the key to walking batfish survival. As with some other aquarium pets, their care of a healthy batfish is simply atypical; people have assumptions about how to care for a fish, that do not apply to all aquarium fishes.

These animals will eat prey such as bristleworms, so they do better in an established tank that is rich in 'hitch hikers' - though these are the sort of benign organisms, that keep the aquarium tidy. However their main prey are crustaceans and small fish; thankfully they acclimatize to a diet of chopped seafood, as from the fishmongers. Caution must be taken that other animals do not snatch the same food so greedily that the poor batfish gets none; otherwise these anglerfishes are compatible with tankmates that are too large to be swallowed. In a sufficiently large aquarium it is even possible for batfish to cohabit, though they can be standoffish to one another. Also they can scuff themselves on hard aquascape, which by its nature limits their ability to roam as on the wild. The substrate should be quite level, and the aquarium should have a footprint that is broad in two dimensions.

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There is much ado about which plants are reeds or rushes; the word 'rush' comes from a very old word related to weaving or knitting, and therefore to an ethnobotanical, economic use for such plants, rather than a botanical label in the stricter, modern sense. The related term, 'reed', is a West Germanic word of uncertain source: it is unknown in both North Germanic and Gothic. The word 'cane' comes to us from Latin as it derives from 'canna', and can ultimately be traced to a Mesopotamian source referring to reeds, canes, pipes, arrows, and measurement. The word is cognate with 'channel' and 'canal', indicating an ancient, watery association.

In botany the word 'rush' came to be associated with the genus Juncus, henceforth the 'true rushes'. Yet whilst tall rushes and their kin are among the plants that clothe wild watersides - and that water gardeners cultivate as marginals - there are also short species of rush. One of these is quite widely cultivated in our aquariums: it is the lesser creeping or soft rush, Juncus repens. This species is best associated with the southeastern USA, with records from such locations as Mexico and Cuba. In the wild, J. repens is a habitat generalist, which adapts to streams, ponds and lakes, and manmade ditches.

Wild J. repens possess two growth forms, one terrestrial which can reach 1 and a 1/2 meters, or 60 inches; and the other is, of course, the submerged form of interest to aquarists. This form even flowers underwater, so there is no question that J. repens can grow as a true aquatic plant - a fact confirmed by many aquarists. Although it's rhizome is quite short, it spreads using modified, prostate shoots, and can thus spread quite well. In the wild it is considered an effective competitor. Ecologically, J. repens shows some preference for a wet, acidic environment with slightly enriched nutrient conditions. It is less common where the pH exceeds 7 but can tolerate as low as 3.5. Beyond this, the rush has a broad ecological range.

In the aquarium, J. repens has earned a reputation as an undemanding, hardy, and versatile grass-like plant, that is commonly used in the mid- and backgrounds of aquascapes. This rush has 'medium' light demands, but tolerates brighter light. It does not really need CO2 dosing specially. In the aquarium it commonly grows to 10 centimeters or 4 inches tall, though 30 centimeters or 12 inches is certainly possible. This fine plant tolerates the temperatures of ordinary, tropical aquariums, because the summer temperatures within it's native range may be so high.

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Few fish have the untapped potential to captivate and amuse aquarists, as do the flying gurnards, of which only one species - Dactyloptena orientalis, the oriental flying or helmet gurnard - seems ever to be traded. Yet few aquarists ever attempt their care. These cute and interesting fish do not belong to any of the major clades or 'families' of marine aquarium fishes, though they somewhat resemble the mandarinfishes, to which they are, actually, quite related. D. orientalis can reach 40 centimeters, or 16 inches long; but more commonly they are half this length. It is a benthic species, native to sandy bottoms in shallow, Indo-Pacific waters, and all the way from East Africa to the distant Hawaiian and Pitcairn archipelagos.

The name 'gurnard' originally applied to triglid scorpionfishes, which through convergent evolution, have evolved a few traits shared with flying gurnards. Formerly, the two clades were assumed to be related in the sense of evolutionary kinship, though this is due to the wonders of convergent evolution; flying gurnards are not scorpionfishes at all. Another early misconception surrounds the supposed flight of the flying gurnards; earlier naturalists had assumed the large pectoral fins, which have a different shape to those of the exocets and freshwater hatchetfishes, were actually aerofoils.

Although flying gurnards possess wing-like pectoral fins, they do not swim close to the water surface, and therefore they are unable to escape dangerous predators by gliding through the air. Like the true gurnards, they have achieved the ability to walk by making use of their paired fins; unlike the kind of skeleton that exists in the limbs of four footed vertebrates, both kinds of gurnard have evolved a series of jointed limbs that are modified from the bony rays of ordinary pectoral fins, and thus resemble human digits. Indeed, it is amusing to watch flying gurnards forage, using their anterior limbs to sense nearby food. These structures constitute true, jointed legs, and these fish can truly walk on the seabed, and they walk more often than they choose to swim.

Both, unrelated, types of gurnard also have expanded, wing-like pectoral fins, that are used for display; and pelvic fins that support the body from underneath, allowing the fish to move along the seabed. They also share the ability to communicate by making grunting sounds. Such an ability has evolved a number of times in the history of the fishes, and aquarists find it characterful; unsuspecting aquarists can also be puzzled by the sounds made by 'talking fish'! These noises are produced in the swim bladder of these fishes; unlike certain bottom living fishes, both true and flying gurnards have not reduced or lost their swim bladders - structures for which they have a use; not only for sound production, but because they walk with their bellies held off the seabed, which means the fishes benefit from some bouyancy.

However it is the paired fins of both types of gurnards, that is the most striking; and to most people, the notion of a walking fish is more wonderful than even a talking fish. Flying gurnards have so modified their paired fins, that their pelvic fins apparatus is not even visible from above, when the pectoral fins are outstretched. In their typical walking gait, the flying gurnards employ their pelvic fins, with extra thrust from their tail ends; at higher speeds, the pectoral fins are unfurled like great wings, which provides them extra lift; therefore,the expanded fins are not simply useful for display. (But when the fish swims, the reverse is true; the pectoral fins are folded during high speed swimming, so as to reduce drag.) The ordinary walking gait of flying gurnards, is bipedal, explaining why they have re-oriented their mai walking legs,to give the fish support beneath their bodies.

One of the amazing things about flying gurnards, is their adaptation to use the anterior portion of their pectoral fins, when procuring food beneath sand. Each pectoral fin has two distinct sections, that are articulated separately on the pectoral girdle, where the fin meets the torso of the fish. Thus the anterior portion is functionally distinct from the 'wing' behind; the anterior fin is itself composed, mainly, of jointed fin rays, that are tactile and used for both feeling and non-bipedal walking. But these legs or digits are preceded by a robust and unjointed anterior ray, that the fish uses to unearth food by digging. Is there nothing a flying gurnard cannot do?

Flying gurnards are found associated with seagrasses, and in other inshore habitats where the bottom is suitably soft and sandy, for them to dig up food. Their dietary niche is as foraging benthivorous carnivores, consuming mainly small arthropods, as well as similar items, such as small fishes, burrowing annelids, and bivalve molluscs. Flying gurnards strictly feed from the seabed, and not up in open water at all. Although they are entirely carnivorous, they can hardly be considered as hunters, and their entire anatomy and behavior is geared to suit a life looking for food lying just below the sand surface. For protection whilst they are foraging, flying gurnards possess body armor.

Although flying gurnards do not have enormous mouths, and are neither fast persuit hunters, nor are they ambush predators, they can and will eat small fishes and other motile animals. Similarly, their natural diet tis composed of the sorts of helpful creatures, that people want in flourish in their sandbeds. However flying gurnards are entirely benign to larger animals they will not see as food, as well as to plants and corals. Their own diet in the aquarium, ought to be meaty, defrosted fare.

Because they are genuine walking fish, flying gurnards require an aquarium with an appropriately large and unobstructed area of substrate. They do not make use of the rockwork that is available in an aquascaped reef tank, and their need is for a soft substrate of sand. Flying gurnards are more active than are some other benthic fishes, therefore they do need more space in the aquarium, so that they can roam around, and in doing so, they will be sure to entertain.

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Dorling Kindersley (odt abbreviated to DK) are a famous and prolific publishing house, respected internationally for pumping out countless titles of various quality, but always impeccable aesthetics. Perhaps unsurprisingly, given the popularity of aquarium pets, a few examples of their output now, have been aquarium related; this is Aquarium Fish belonging to the Eyewitness Handbook series; the cover blurb from 1993 promises coverage of more than 500 fish species, and the author is Britain's own Dick Mills.

Mills was at one point a very well known author, but his name is usually associated with the Interpet titles, rather than the output of the US-based Dorling Kindersley Most people might be familiar with those Eyewitness books that focus on travel destinations, for they are extremely popular - providing a different, more visual approach to travel than, say, a Rough Guide or Lonely Planet equivalent. But DK have in fact produced a plethora of other books, and even CD-ROMs, under their iconic Eyewitness label.

Because the format of this book is, basically, that of a field guide, it has not much focus on the pragmatic matters of running an aquarium. There is some information of this nature, right at the beginning of the book but not enough to detract from it's main focus - the aquarium fish. Mills poses for us, the question, 'What is a fish'? This sounds idiotic to most people; but since zoologists abandoned Pisces (it had become a waste basket taxon) the concept of a fish has lacked a scientific definition.

Oddly Mills does not attempt to answer his own question: instead he begins a superficial and illustrated coverage of piscine biology. He presents the tropical freshwater fishes as belonging to a few categories - cyprinids (carp); characins (tetras); cichlids; anabantids (labyrinth fishes); kilifishes; catfishes; loaches; 'other tropical aquarium fishes' (basically, 'oddballs'); and tropical livebearers (though really they are kilifishes, too, but it is customary to treat any and all livebearers apart from egg laying fishes).

It might be noted that the field guide format of the book, is poorly suited to conveying much information by the sidelined text. Yet as a photographic reference, the book excels. Each entry is illustrated by stunning photographs, which are perfect for identifying live fishes. Most of the entries represent a natural species, although sometimes a domesticated morph is featured, for example the goldfish and koi varieties. Many of the images capture the beauty of living fish perfectly well, and one wants to turn the page, just to see more pretty fishes.

Cyprinids, by custom, are classified into vernacular categories based on appearance, moreso than their relationships to one another. So it's unsurprising that Mills presents an impressive array of fishes named barbs - a word which, truth be told, is really an exoticising way to say 'carp', for in English is used only for foreign, mainly Asian cyprinids as we encounter in the trade. Mills also presents several rasboras and danios, some so-called 'sharks' (which is short for shark-minnow) and one or two minnows; but of course, the genus Garra cane to aquarist's attention too recently to be included in the book. There is not a single species of Garra in the book, but nowadays, they are mainstream in the trade. Aquarium history is like that.

The entries on tetras feature a good many well known species, such as the petite and popular rummynoses, cardinals, and the like. But Mills does not ignore the less familiar characins, such as the anostomids, that new aquarists might simply see as some weird fish. He also features the hatchetfishes well, which are a personal favorite of mine, and also a few interesting African characins. (Excepting the Congo tetras, all of the popular tetras are in fact South American.) Mills features more of the pencil fishes than one might expect in an early 1990s book, and also I'ma nice selection of basal, non-carnivorous piranhas - oddly, only one of the 'real' meat eating piranha species has an entry.

In my own opinion, the section Mills devotes to the cichlids is visually exceptional. The photographs really capture the appeal of small cichlids in their full vividness. As one reads what is, basically, a field guide to your local pet shop, the inner aquarist itches inside oneself to buy more cichlids. And the broad smorgasbord of little cichlids is not limited to only Apistogramma, Pelviachromis, and Mikrogeophagus, either.

When it comes to the plethora of East African lake cichlids that are native to 'Darwin's dream ponds' - meaning the ancient lake ecosystems of the Great Rift Valley' - Mills capably presents them for our eyes. The beauty of these cichlids can truly rival that of the coral reef fishes, and the freshwater lakes do indeed have rocky reefs, although of course they lack corals, which are purely marine.

He doesn't however separate the Rift Lake cichlids by their lake of origin - which would, perhaps, be senseless. Unless one is being strict about biotopes, Malawi and Tanganyika cichlids can cohabit together, in hard and alkaline freshwater, as represents their natural habitats. As long as the water is hard and alkaline, the exact pH does not really matter for these fishes.

The pages on gouramis and their allies only mention the controversial Betta splendens in a single entry. To many aquarists, this would seem odd today, and the name 'Siamese fighting fish' has all but disappeared from our collective vocabulary. Nowadays we just call them bettas, although this ignores that Betta is an entire genus of gourami - Mills himself features related, wild species of Betta on his pages.

At the time, the care of domesticated bettas was widely misunderstood, although the domesticated species had been bred into strains for generations, and the species is extremely hardy. At the time, the little fighting fishes were treated appallingly by retailers, so the history of betta care is a dark chapter. However although I'm aware of westerners fighting male fish of this species - a form of blood sport - the ornamental finnage of the colorful, domesticated strains we see, was not bred into them, just for it to be torn apart in a blood sport.

Misinformation about the species also had it, that the males are violent toward other fishes ; most bettas are placid towards tankmates such as catfishes, loaches, and tetras in community tanks. Of course their beautiful fins, for which the have been selectively bred, attract the unwanted attention of fin nippers, so care must still be taken. Yet it still feels odd that Mills devotes pages to domesticated angelfishes and discus, but not to 'siamese fighting fish', even back in 1993.

Proceeding through the book, we are introduced to a good number of lovely kilifishes, although let's be honest, few of the egg-aying kilifishes are regularly seen in pet stores. The catfish selection is broad but it feels a little odd today. As we might well expect there is a good selection of the popular Corydoras genus, and the loricarids. But among the latter, the delightful and hard working otos are represented by only one species.

Like the aforementioned garras, the otos or dwarf suckermouths rose sharply in popularity, only following increased hobbyist interest in managing lushly planted aquascapes., Such settings require small, herbivorous fish for that will control algae, without damaging live plants. Not much is presented about the genus Synodontis, either, although they had a decent number of admirers in 1993.

Following the coverage of the catfish clade, Mills moves on to introduce those other, classic bottom feeders, the loaches. Although he presents a good variety of loach species, that we might identify at the tropical fish store, I find it odd that his selection does not introduce a single hillstream loach. At the time a species of the latter was commonly sold as a 'Hong Kong plec', although it is, of course, neither a 'plec' nor a catfish.

Rainbowfishes are featured among the oddballs, although by 1993 they were surely more familiar, to the average freshwater aquarist, than were the kilifishes. Mills seems to feature as many rainbowfish species as he does loaches, yet he does not present them in a separate category of their own, as he does the former. One cutious inclusion among the roster assigned to the oddballs, is Gyrinocheilus; this streamlined grazer was understood to be a carp, or cyprinid, even then.

Naturally Mills treats us to gobies and gars, knife and leaf fishes, spiny eels, ekephantnoses, et cetera. Speaking of gobies, some species that are reasonably popular today were all but unknown to British aquarists back then - there are no species of Rhinogobius, and none representing Stiphodon.

Curiously, although brackish environments are saltwater by definition, Mills lumps brackish associated scats and monos, into the freshwater oddballs; he provides no categorization of brackish fishes as neither freshwater nor marine. Until fairly recently this was a convention in the UK, but scats and monos are nowadays more likely to be lumped in with marine fishes - and traded as such.

Mills finishes his guide to the freshwater tropical species, with a surprisingly good variety of livebearers, including goodeids and a halfbeak. Although he does not truly dwell on the great variety of our domesticated livebearer morphs, he nonetheless treats our eyes to some very lovely swordtails, platies, and the like,

I find it odd that the domesticated livebearer morphs are ubiquitous in aquaria, whereas the keeping and breeding of wild livebearers has remained so very niche - although they are also easy to care for, and many of them are suited to community tanks. Simply by showcasing so many wild livebearers, Mills reminds is that the livebearers are not just black mollies, fancy guppies, and the aforementioned, similarly domesticated platies and swordtail breeding strains.

Mills does not stop at introducing us to tropical fish, for he showcases those for the unheated aquarium as well. Naturally enough, this section of the book has a strong focus on goldfish, and also koi, although our friends the koi are more associated with outdoor ponds, than indoor aquariums. However Mills covers other coldwater fishes better than most aquarium writers, after he presents the goldies and koi.

Somehow, some of the selected images capture the metallic sheen of some goldfishes outstandinglyy. Experienced fishkeepers often shun 'goldies' - excepting, of course, their diehard fans. But I am still partial to a metallic looking, relatively 'natural' common goldfish. I also like the yellow color morphs as well.

Whereas, although I believe animal domestication is not immoral, I actually am skeptical of selective breeding that distorts the form and function of wild-type animals, without a practical purpose to either man or beast. All living animals deserve dignity, and not a predisposition to disease, or a need for humans to trim their 'wen' so they might continue to see. Humans should breed their livestock responsibly, without imposing genetic impairments.

But Mills does not limit his coverage of coldwater fish, to the fancy goldfish and koi strains. Back then there were fewer controls upon which temperate climate species, could be imported or traded in the European Union, and Mills introduces us to fishes for room temperature tanks, that the British don't really get to see on sale anymore; although the 90s saw a fad for alternative species in room temperature tanks.

In particular, Mills features the North American freshwater sunfishes or centrarchid perches. These are a very important clade in North American freshwater ecosystems, but they are not familiar as aquarium fishes today. He also features a few cyprinids from Europe, Asia, and North America; cyprinids rule the northern continents as characins do South America.

Marine tropical fishes are introduced by the clownfishes - though they are really a subgrouping of damselfishes, aquarists usually consider tham as though they weren't. At the time, the nowadays popular,captive bred morphs of clownfish were not yet available; indeed, it was considered almost impossible for aquarists to raise baby clownfishes, although they paired up, spawned and hatched fairly regularly, and without prompting by man.

The charming clowns of the reef are followed by the angels and the butterflies. As with the pages presenting freshwater fishes, the photos of marine fishes trully present the striking colors and color patterns of fishes well. And what fishes have such color, as do the marine butterflyfishes and angelfishes?

As might be expected, Mills features a good number of damselfishes and tangs: he also as presents all the main groups of tropicalmarine fishes, that might be listed by a saltwater hobbyist: blennies, cardinalfishes, gobies, groupers, and the like, are all mentioned. Although some fishes inexplicably share a page with a heading that defies reason, and others are misclassified to a category - why not 'other tropical marine fishes'?

The diversity of groups like blennies and gobies feels severely understated, though; at the time such fish were sold genetically, without great effort towards identification - just the vague labels 'assorted' and 'miscellaneous' would usually be regarded sufficient. To this day a lot of gobies and blennies are only loosely identified; and the two categories categories are informally and inconsistently applied, so as to include such unrelated fishes, as sandperches, dragonets, and the mysterious Pholidoichtbys.

It has been ages since I last saw native marine fishes sold in a pet shop. People with an interest in the topic, either have to find their own by the seaside, or if they can, they must trace a specialist supplier. But Mills nonetheless treats us to a few coldwater marine fishes, of North Atlantic and Mediterranean origins. (Oddly, he hides the Catalina goby from California, among the tropical fishes, although it cannot survive the higher temperatures of a reef tank.)

The focus here is on subtle colors and interesting forms and behaviors, for this is the world of the lumpsucker and it's sculpin allies, and of the clingfishes, blennies and gobies of our own native rock pools What Mills does not mention is that some of these species will require a chiller if they are kept in a centrally heated, British living room all year round. Keeping true to the title of his book, Mills does not introduce us to any tank inhabitants, other than the fishes.

This is not a book that identifies corals, anemones, hermit crabs, clams, conches, sea urchins and cucumbers, or starfishes. In his pages about the freshwater aquarium, he does not introduce us to the shrimp, crayfishes, or snails; nor does he touch the aquatic amphibians and reptiles. No pages are devoted to saltwater macroalgae, or freshwater macrophytes, either. His firm focus is on fishes, and not cartilaginous or lung bearing fishes; he appears to define 'fish' phylogenetically, as do I.

As a guide to knowing which fish species is which, Aquarium Fishes is both a capable and a very, very stunning work. In fact, I cannot think of an aquarium book, that is illustrated with better visuals, than is this one. I could simply ogle the pages all day, the way lonely men ogle at pornography. This book is truly 'fish porn', but remember it is light on informative details.

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Today I was asked how to care for a New Guinea crocodile skink (Tribonolotus so ) with an obvious skin infection. The dermal scutes were discolored and one was rotting, revealing exposed, pink tissue. Of course I am not a veterinarian, but there are basic first aid solutions all reptile owners ought to know, and basic advice to be given about treating poorly reptiles.

If possible the lizard should be taken to a veterinarian, who would prescribe antibiotics - something I am unable to do. However, most vets have minimal experience in reptile care, and not much is known about the care of specific species of low economic value, anyway. Given the improbability of knowing an expert vet, care must - realistically - begin DIY. Fortunately the basic treatment of skin ulcers and infected wounds is not very difficult.

If you, as a human, have ever had a serious cut or external ulcer, it's likely the cut was swabbed with iodine. Iodine has strong disinfectant properties, and is safe for all vertebrates, though it can sting; obtain povidone-iodine which is usually available as Betadine. This can be swabbed on affected, external areas using cotton wool to dab it on and around the affected tissue.

People often keep crocodile skinks is a rainforest vivarium, and provide them sufficient water in which to submerge, as they do in nature. But these conditions are unclean as regards a wounded or ulcerated skin, zo the animal ought to be kept at the right temperature in a hospital setup. By this I mean a temporary vivarium with a changeable and disposable substrate of food grade paper.

The humidity should be lower in the hospital setup, and if possible, the water in the dish ought to not cover the damaged skin. Of course veterinary assistance might be needed, and suitable antibiotics can be purchased without a prescription in some countries. But still, a reptile keeper ought always to have iodine solution to hand, and also the right kit to set up an emergency hospital.

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The clade of shrimp called pistol or snapping shrimp, are one of the most commonly traded clades of shrimp in the aquarium trade. The species in question are those with the habit of forming symbuotic associations with particular fishes. Such a shrimp species is Randall's pistol or snapping shrimp,Alpheus randalli, which is also traded as the red and white striped pistol shrimp. Among the pistol shrimp this species is outstanding for its distinctive, red banded color pattern.

A. randalli is indigenous to parts of the Indian and Pacific oceans, at tropical latitudes. There it associates with gobies of the genera Amblyeleotris, Stonogobiops, Tomitamaichtgys, and Flabelligobius. This shrimp reaches a length of 3 centimeters, or over 1 inch long, so it is suitable for small aquariums. As this species is nainly a detrivore, it is not difficult to feed it in a reef aquarium with an established sandbed. When they are housed in established aquariums, these gentle shrimp will not need feeding per se, as their food will already be abundant in the substrate

Pistol shrimp are often confused with mantis shrimp because of the noise they make, which frightens paranoid fishkeepers. The claw and the noise it creates are actually of scientific interest, and they are very different, in fact, from the striking arm of the mantis shrimp clade. In fact snapping shrimp cannot employ their claws to hunt large animals, as do mantis shrimp, and the two kinds of crustacean are dissimilar as well as only distantly related: the snapping shrimp is more closely related to crabs and lobsters, in fact.

The claw of the snapping shrimp is employed as a weapon, though not one that is used to subdue large victims. If anything, their impressive claws are more amazing than are those of the mantis shrimp clade; for they have evolved to produce powerful bubbles of air, to blast and stun an opponent. Pressure increases when the claw opens wide, at which point surrounding water flows into a small chamber at the bend of the claw, which was once an ordinary shrimp pincer. Rapidly the claw snaps together, causing a small plunger to force out the water by pressure. Thus the shrimp launches the trapped water as a high speed projectile - these animals are truly a marvel of natural selection. But they can neither hunt fish nor break aquarium glass.

The habit of A. randalli is to dig into fine grained sand or silt substrates, and thus this species requires a suitable sand substrate in the aquarium. They make use of coarser material such as coral or seashell fragments to reinforce their burrow walls, therefore these elements must also be mixed into the otherwise fine material of the aquarium substrate. Despite the frequent and paranoid confusion of snapping shrimp with predatory mantis shrimp, they are in fact peaceful to ornamental fish and crustaceans. They are also completely harmless to corals and macroalgae, but although they can survive unpartnered with a goby, it is inauthentic for both species fare better together in the wild.

Gobies of the prawn associating species associate and partner with a snapping shrimp such as A. randalli, after the shrimp has begun to burrow itself a new home. That only young shrimp usually live without a goby partner, indicates the extreme usefulness of the remarkable shrimp-goby partnership to them in the wild. A pistol shrimp without a burrow is extremely vulnerable to predators, and such a shrimp without a burrow will instinctively not feed whilst it concentrates all of its energy on excavating a safe, basic lair. The goby is better than the shrimp at watching for predators - like a watchdog, whereas the shrimp performs digging duties, and has the defensive weapon.

Like the photogenic association of clownfishes (Amphiprion sp.) with certain sea anemones, the association of gobies with snapping shrimp, is a textbook example of mutualism - the close and habitual co-existence of two organisms, that bestows benefits to both the living things in the partnership. The relationship and co-operation of gobies with snapping shrimp is one of such friendships that can be stimulated and observed in the aquarium, because both animals are easy to care for, and fascinating to watch as they behave as they would in the wild.

Generally snapping shrimp are simply traded as snapping shrimp, either alone or partnered with a goby as a pair. Alpheus randalli is distinctive enough to be traded; other distinctive species include A. bellulus, the tiger pistol shrimp, a close ally on A. randalli that may be considered similarly by the aquarist; although A. bellulus is the larger species, growing up to 5 centimeters or 2 inches long. Although the two species share a banded color pattern, that of A. bellulus is brownish against yellowish white.

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Sticklebacks have not captivated aquarists since the days when children went pond dipping to stock their aquariums. However Germans have lately imported an oriental species, Pungitius sinensis, the Amur or Chinese nine-spined stickleback. P. sinensis are small fish, growing usually to 6.5 centimeters or under 2 and a 1/2 inches, and sometimes 9 centimeters, or nearly 4 inches in length; reportedly, in favorable Korean environments, they reach 15 centimeters, or 6 inches long. This species is eastern Palearctic in its distribution, being native from Siberian locations like Kamchatka and the Amur basin, southwards to northern China, and is also present on nearby islands such as those of Japan.

Sticklebacks have long confused ichthyologists, enlightened ethologists, and amused children. Historically they were assumed to be related to the seahorses and other pipefishes, although this systematic position is now disfavored; instead they are thought to be related to the sculpins and eelpouts. Their namesake spines are, in fact, robust fin rays, which are the defence of these curious fishes. Sticklebacks are well studied for their complex behaviors, and this includes their nest building activities for the purpose of parental care. These are psychologically complex fishes, in a way that is easy to study, and should encourage us to respect fishes as we do other animals.

All the sticklebacks are native to the temperate zone, and therefore none of them can be considered as suitable fishes for tropical aquariums. An aquarium housing any P. sinensis should not become too warm, and ideally it seems the water temperature should not exceed 18 degrees centigrade. (Perhaps this species is one of those, that would well benefit from a chiller?) The entire stickleback clade are also considered to be carnivorous, consuming tiny arthropods and other small prey. In the aquarium defrosted items will be accepted, if they are of a suitable nature for microcarnivores. Upon hatching, the baby sticklebacks are known to begin subsisting on biofilms, from leaving their nest until graduating into carnivory.

P. sinensis is associated primarily with clean and well oxygenated freshwaters, although adult fish are able to survive even in marine environments However when this species is in saltwater environments, it's ability to build nests using a sticky secretion as a natural glue, appears to be curiously impaired; furthermore the offspring cannot survive a low salinity of 8 ppt. This is essentially a freshwater stickleback, one that seemingly fares best in downstream pools, thickly grown with plenty aquatic plants.

Natural nest building, which is performed only by the male fish, will obviously require suitable aquatic vegetation; it is the male stickleback that builds and guards his nest. Members of the genus Pungitius may be housed together with similarly sized fish, with similar environmental requirements, however their compatibility and broader captive care is not so well documented, as are those of the three- and fifteen-spined sticklebacks, which belong to allied genera. Incidentally sticklebacks are so individually variable, that the genera are difficult to demarcate using what seem to be obvious traits, like the number of dorsal spines they happen to possess - despite our habit of naming species by a number of spines.

Not much is written about the care of sticklebacks other than the three-spined species. The latter has a reputation as a fin nipper, with the males being more aggressive than the females; yet this is subject to individual personality, and wether the fish are in nesting mood. I have never witnessed aggression among the marine, fifteen-spined sticklebacks, but then again, I have never seen them nesting in a community tank: at other times, they were docile and unaggressive,at least towards pipefishes.

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In addition to the soft octocorals and the stony scleractinian corals, which are always called corals, and the actinarian anemones, there are some clades of flower-like animals, which may be viewed as either. Of course the distinction between a coral and an anemone is not, entirely,a natural one; the archetypal coral was an octocoral, prior the the discovery by westerners of tropical, shallow water coral reefs, dominated by reef-building scleractinians, primarily the acroporids. After the coral reefs captured the western imagination, stony corals became 'the' corals most people have in mind. Whereas the archetypal anemones are the actinarians, also known as 'true anemones' for this reason.

The zoanthids (or sea mats) are not actinarians, nor are they either octocorals, or scleractinian corals. This does not stop people shoehorning these creatures into the categories of 'anemone' or 'soft coral', and many people trade their colonies, attached to a fragment of a hard substrate, as 'polyp rocks' - a pragmatic descriptor that is shared with the unrelated corallimorphs or 'mushrooms', and certain octocorals. Zoanthids are also called 'button polyps' which reflects their appearance; they are often traded as either 'zoas' or 'palys', though sometimes this is based more on appearance than on genetic membership to either of the namesake genera, Zoanthus and Playthoa.

Outliers in appearance among the zoanthids in the aquarium trade, and not as common as either Zoanthus or Palythoa, are the snake polyps of the genus isaurus (sometimes mis-spelt as Isaura). Really these are one of the more offbeat and quirky choices of coral - if we call them such - that are hardy enough even for beginners. The species seen in the trade is known or assumed to be I. tubercularus, the knobbly (snake) polyp; this is a species recorded from both the Atlantic and the Pacific oceans, where is is encountered as an intertidal species, that in worldwide in warm seas, dwelling in rock pools between the tide marks.

Such are extremely difficult habitats for many organisms to survive in, for the simple reason that their environments are unstable, and prone to swing to extremes even within the course of a day. Of course this limits the number of predators in these micro-environments, so species specialised to tolerate rock pool extremes, may flourish there with low defences, and low need for them. I. tuberculata inhabits rock fissures and accesses the water column by reaching about 10 centimeters or four inches high. These are a nocturnal feeding species, and they also play host to internal symbionts, for the purpose of photosynthesis, giving them a brownish color. The species is, however, variable in its appearance. It is also reported from other shallow water environments, from high to low energy in nature; for example rock pools are periodically (but not constantly!) blasted by the tide, whereas I. tuberculata is also recorded in sheltered lagoon environments.

Snake polyps, also known as warry sea mats, are not considered difficult to care for in the least. These are rugged creatures adapted to resist harm that would destroy many other kinds of coral and anemone. Of course it might be borne in mind, that all fleshy polyps could entice bites from animals inclined to bite on fleshy objects; nothing is 'reef safe' in any idealized sense. But relative to some of the button-type zoanthids, the snake polyps are themselves less inclined to clothe the entire, available surface area as aggressive colonists, which can bring some zoanthids into conflict with other ornamental corals, and with human aquascapers. In all I. tuberculata is, in fact, a very easy coral, and a nice novelty coral, for anyone with the knowledge and means to provide basic care for corals. Low to moderate light is best because this species retracts by day and lives in turbid habitats; the flow regime should be turbulent, but no more than moderate in strength.

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Some of the most iconic fishes on the coral reef are the marine angelfishes or pomacanthids, fishes that are reef-associated and strictly marine by nature, and completely unrelated to the popular freshwater cichlids also known as angelfishes. It is unsurprising, then, that aquarists have often expressed an interest in keeping saltwater angelfishes in expensive aquarium aquascapes featuring living corals and clams. Opinions about this range from those alarmists who say it is impossible, to those boasting that they have in fact done so without consequences. The concensus of opinion would have it that the endeavor is risky: it does indeed that some individuals within certain species, will take bites out of corals or clams, whereas others would not. This does not help the aquarists to choose a 'reef safe' individual fish, of course, but it does explain the variance in the anecdotes about angelfishes in reefkeeping.

None of the angelfishes is a specialised corallivore, or coral eater. This does not mean that they are physically or physiologically incapable of eating coral tissues, and in fact it is verified that some large angelfish species do, in fact, consume corals and anemones as items within broader diets, in the wild. For example pomacanthids are adapted to accessing prey that are in and around crevices, and pomacanthids are known to extract and consume live sea anemones. It is unsurprising that such broad spectrum feeders will behave similarly when they are in captivity. Early on in their evolutionary history, pomacanthids evolved the ability to close their jaws whilst they are extended, as during normal suction feeding. This ability to bite down whilst reaching to items attached to the seabed, allows them to grip and tug efficiently at tough masses of sponges and colonial tunicates - items that are much more difficult for other fishes to eat. They are specialised in a very different way to the butterflyfishes, which also consume attached animals, but trend towards the evolution of corallivory. The difference is that between a horse and a deer on land, or maybe that between a white and a black rhinoceros. Angelfishes partition resources with butterflyfishes, because they eat in different ways; angelfishes as a whole are not inclined to be selective feeders, and they chomp indelicately at masses of tough, living tissues, whilst the butterflyfishes instead tend to nibble more selectively.

Surrogate behavior is thought to explain why individual angelfish start to bite corals and clams mantles in the aquarium. In the science of behavior, surrogate behaviors are those that arise when a natural instinct cannot find natural expressions; so that in humans, for example, shopping becomes a surrogate for gathering foods. Angelfishes in the wild, are surrounded by spongal growth and tunicate colonies, and the behavior of feeding on then consumes a great amount of their time. Not surprisingly a frustrated angelfish will not improbably begin to bite on surrogate items, in the same way, if the normal targets of such behaviors are not present. That some fish do this more predictably than others in the same species, is presumably due to personality traits such as curiousness and a tendency to act upon natural impulses - otherwise the unpredictability of coral and clam biting by angelfishes is inexplicable. The phenomenon is noted even in an unusually specialised non-coral eater (ie. Pygoplites) as well as the more typical, broad spectrum feeders.

The diets of all angelfish are not equally well known, but as a clade, their anatomy is well studied as regards eating and digestion. Individual variation in behavior must be borne in mind, alongside the fact that some angelfish species actually have are faculative coral eaters in the wild. Most worry is expressed over the dwarf angelfishes - classically the genus Centropyge, but now three different genera - which older books as late as the 1980s, used to categorise as 'reef safe' - a meaningless term that ignores the realities of ecology, but one broadly defined as something like 'compatible with and harmless to living corals, and all (or almost all) sessile invertebrates'. Many dwarf angelfishes do, in fact, have diets rich in sessile, attached animals, and such items can even predominate in their diets on the reef.

The confusion perhaps arose from comparative anatomy: Centropyge teeth resemble those of blennies, another clade that consumes much algae, but cannot be regarded as strictly herbivorous, on the whole. The same older books used to tell the reader that blennies were reef safe, without reservation: in reality many eat coral polyps as natural parts of their diet, and one genus eats only stony coral, despite not having obvious craniodental adaptations to coral eating. The comb-like teeth of blennies, and of dwarf angelfishes, are actually efficient 'multi-tools' for using on a range of foods - like the chisel-like teeth of rodents, or the toothless beaks of birds. Even as fishes with comb-like teeth are restricted so as to not consume certain items, they can have either broad or narrow feeding habits, and eat either animal or vegetable resources.

Centropyge have teeth adapted for benthic grazing, and they resemble blennies and mbuna in this respect. They are among the most herbivorous angelfishes, but their diet still includes sponges and tunicates, and again dietary isotopes indicate extensive omnivory exists in these fishes. In the aquarium they do nip at coral polyps and clam mantles, so they ought not to be regarded as 'reef safe'. The Paracenteopyge angelfishes are basically carnivorous by nature. They should not be confused, ecologically speaking, with the dwarf angelfishes of Centropyge proper, or the pygmy angels of the genus Xiphypops; but their diet is not well documented in the literature, only that they eat sessile animals, and although the can be encountered in the shallows, they are more often associated with deeper reef habitats.

Xiphypops, the pygmy angelfishes, are different from the Centropyge angels, because natural selection has helpfully reorganized the orientation of their faces for a lifestyle of herbivory by dislodgement. Although I have again heard of pygmy angels nipping at tridacnid clam mantles, they are by far the safest of the angelfishes in coral aquariums. They simply possess too much specialization for a specific type of herbivory, for them to destroy corals. Again I offer the caveat that these animals may sometimes nip at fleshy polyps, although I have never witnessed this. Truthfully, the pygmy angels are specialised, obligate consumers of delicate and foliose algae, which they eat using combing and shearing strokes of their downwardly inflected jaws.

Two other genera of angelfishes can be considered, on phylogenetic grounds, to be allies of the dwarf angelfishes; these are Apolemichthys and the surprisingly planktivorous Genicanthus, or swallowtail angelfishes. Members of the delightful genus Apolemichthys are understood to be omnivores, with a diet that is dominated by sessile animals; specifically, some 3/4 of their diet in the wild is spongal. The diet of this genus in the wild, is not so well studied as some of the other angelfishes, although these are wonderful fish indeed. Whereas their allies Genicanthus have abandoned their lifestyle of benthic feeding, and they display evolutionary reversals associated with open water planktivory. Genicanthus are thus the most extreme outliers of the angelfish group, in terms of their unique feeding ecology and behaviors. For this basic reason, these specialists are considered to be entirely 'reef safe' among the angelfishes. All the same, Genicanthus in the wild are known to consume some benthic algae and sessile animals. To my knowledge they never eat anything that we would think of as corals when they are in the wild, and I regard these specialists as about as appropriate for reef aquariums, as are Xiphypops.

At the other end of the spectrum of specializations that are observed in pomacanthids, is the regal angelfish, Pygoplites. For Pygoplites are the most specialised of all angelfishes for a life of gripping and tugging tunicate and spongal masses, to the point that wild Pygoplites will consume nothing else at all. Nonetheless, aquarists have sometimes noticed that they appear to bite at 'softies', a non-zoological catch all category, that contains all popular anthozoans that neither secrete a stony skeleton, nor large actinarian anemones. Obviously the behavior arises out of frustrated instincts when it occurs, and at least in some cases, the angelfish is likely biting encrusting organisms near the base owhere the 'softies' are attached. Observations that fish happen to bite at coral are not necessarily observations that they eat corals; they can be eating items on their surface or near their base, and people should bear in mind conclusions based only on superficial observations, ought not to be jumped to.

The butterflyfish-like Chaetodonplus are quite reef safe angelfishes, although they have been reported to bite at the fleshy polyps of 'LPS' type colonies, and also at clam mantles. This is even though their basic diet in the wild is spongal and algal - and stable isotopes have determined that they also consume detritus deliberately, making them scavengers. Nonetheless Chaetodonplus are safe in aquariums that feature stony corals with short polyps. Different individuals appear to vary in their destructiveness to other corals, and I had no trouble with mine in a mixed reef. But other people have reported they inflict regular nippings upon fleshy, sessile ornamentals. Aquarists tend to classify their stony corals into the two non-phylogenetic categories, SPS and LPS, but they are poor predictors of coral vulnerability, because the categories ignore the stings and other defences of polyps. However, because angelfishes have evolved to grab and tear at bulky items, large polyps will be at potential risk of angelfish attack, whilst those coral colonies bearing small polyps will not.

The 'large angelfishes' are two wonderful genera of fishes that have long enthralled aquarists - Holacanthus and the archetypal Pomacanthus itself. Before the rise of reefkeeping, the large, showy angelfishes were staples of saltwater fish retailing. When the hobby refocused on smaller systems, small fish, and living corals, they dropped from popularity. And some of the large angelfishes, as omnivores, actually do eat anthozoans by their nature. The subgenus Euxiphypops - unlike their smaller namesakes - are typical angelfishes, as regards their jaw mechanics. However they too have evolved into a herbivorous ecological space, and their faces are able do deal with tough seaweed as a basic diet; they use the same eating techniques that other Pomacanthus angelfishes more normally employ to exploit ruggedly attached, sessile marine animals.

All large angelfishes are disinterested in corals that have branching forms, which means that well established gorgonians and 'SPS' with this growth habit shall be entirely safe from those impressive grazers. However large angelfishes are well known by aquarists and marine biologists, to consume both 'softies' and sometimes fleshy 'LPS'. Polyps the size of zoanthids may be swallowed whole by big angelfishes, and even large anemones may be eaten - and even if they are located in an otherwise inaccessible, well protected position. Large angelfishes are fortunately suited to 'SPS' tanks, although they have evolved to consume anthozoans as omnivores - thus, it is their nature.

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Some very endangered fishes enter the sphere of the aquarium hobby, and even aquarium retail, as a consequence of successful captive breeding for the purposes of wildlife conservation. One such fish is Paretroplus menarambo, the pinstripe damba or menarambo, which grows up to 13 to perhaps 25 centimeters, or 5 to about 10 inches long. Some sources deny the larger individuals, but I can verify their existence among captive bred fishes.

The pinstripe damba is native to the floodplain lakes of northern Madagascar; formerly this species was considered extinct in the wild, and reduced to breeding stick in captivity, before they were rediscovered in the ecologically important site of Lake Tseny. Tseny is a hardwater, alkaline lake with a warm enough temperature of 25 to 35 degrees centigrade,

The island of Madagascar is not, as people assume, simply a sort of strange outpost of neighbouring Africa; she has been regarded as a faunal realm in her own right, equal to the Afrotropical region to which most of Africa belongs. Her origin is that she was once connected, not to Africa, but to India, which migrated north to collide with Asia - a slow process that created the mighty Himalayas, when the rocks of the earth crumpled like a sheet of fabric.

The cichlids of Madagascar are not a part of the African cichlid group, as might be expected, nor of the American cichlids, which would not be expected. Rather, the Madagascan cichlid fishes constitute their own, unique evolutionary subgroup of cichlids; their closest kin are the Asian cichlids called chromides. It is assumed their ancestors lived on Indo-Madagascar, but if this was true, the first cichlids would have to be much older than the molecular clock and their known fossil record might suggest

In any case, the chromide-like cichlids of Madagascar are an ancient group of fishes, found nowhere else on Earth. The same is true of other Madagascan freshwater fishes, such the bedotid silversides, distant cousins of the Australasian rainbowfishes, and the anacharid catfishes. These three clades of fish are unique to Madagascar and must have been present since ancient, geological times. Like the lemurs, tenrecs, and the ground and cuckoo 'rollers', they are truly uniquely animals of Madagascar.

As a genus, Paretriplus sp. are categorized as benthic feeders with a diet of diet and algae, and this holds true for P. menarambo. They seem to be unfussy eaters in the aquarium, but their natural diet ought to be in mind when feeding these omnivores - though they will eat defrosted, meaty items, and pellets based on aquatic animal protein, they lean to vegetarianism.

P. menarambo will do very will in the kind of aquarium parameters that suit Central American and East African lake cichlids. Unlike some of the other Madagascan cichlids, P. menarambo is not found in brackish environments. It is thought that non-native carnivorous fishes have harmed wild Madagascan cichlids, and pushed some species into brackish habitats, the invasive species cannot well tolerate. Thus their fate parallels the effects of cats and foxes on indigenous Antipodean wildlife.

Although currently P. menarambo are still extremely endangered as wild fish, and it feels wrong to think of them as non-breeding display fish, they do appear in the aquarium trade as captive bred surplus stock. And they have proven themselves to cohabit well with other cichlid and catfish species, for example.

Since they have been brought into captivity, first for their own preservation, they have proved to be exceptionally hardy and adaptable fishes, and time will surely see them become more popular. Let us hope that we hobbyists preserve their 'wildness', rather than creating fancier, domesticated strains.