L - Tiktaalik is a monospecific genus of extinct sarcopterygian (lobe-finned fish) from the late Devonian Period, about 375 million years ago, having many features similar to those of tetrapods (four-legged animals). Tiktaalik is estimated to have had a total length of 1.25–2.75 metres (4.1–9.0 ft) on the basis of various specimens...
R - Panderichthys is a genus of extinct sarcopterygian (lobe-finned fish) from the late Devonian period, about 380 Mya. Panderichthys exhibits a range of features transitional between tristichopterid lobe-fin fishes (e.g., Eusthenopteron) and early tetrapods...
Thanks to these guys you get to vote and pay taxes. What a world!
It may not a direct lineage of fish -> fish-o-pod -> not a fish like we see in some diagrams; some of these guys may have lived too close in time to one another to be direct relatives. They do show the progression of lobe finned fishes (like Eusthenopteron) to more land oriented creatures (like Ichthyostega)
Stickers here!
Piscine Wyverns (Clade Vernopisces) are a clade of wyvern-like lobe-finned fish native to certain parts of Chortis. Despite the name, most members of this group can't fly, the best they can do is glide or leap very high. Many piscine wyvern species are also sluggish on land but faster in water.
They are the closest relatives of true dragons (4 ambulatory limbs, 2 wings), though they evolved wing-like structures independently.
Unlike last time, I won't provide scientific names.
Riverhat wyverns are elegant Piscine Wyverns named for their bony heads. Unlike most members of the clade, they are primarily herbivores. Due to their adaptability, they are common in their habitats. A domesticated subspecies is common in many villages.
Element: Typically Basic (though this might vary in breeds)
Kappa are green Piscine Wyverns that have a saddle-like shell somewhat similar to a turtle. Most of their magic lies in the water in their cephalic disc or sara. If the magic-infused water on its head is gone for a long period of time, the kappa will be severely weakened. Kappa behavior is similar to that of dolphins, both being intelligent animals.
Element: Plant/Water or Spirit/Water depending on the population
Mudflowers are social piscivores that live in groups containing 6 to 30 members. Unlike most Piscine Wyverns, mudflowers are capable of flight, albeit they aren't very good at it. The petal-like frill is a derived pair of pectoral fins. Their main method of hunting is swimming through muddy waters as their hindlimbs are poorly adapted for terrestrial locomotion.
Element: Earth/Water
Hipdemons are Shantungosaurus-sized piscine wyverns that feed primarily on amphibians, fish, and reptiles like crocodilians. It is unclear what purpose it's large legs serve though most believe that it might have a function in supporting it's weight on land or defense.
Element: Dragon/Water
Makara are large euryhaline piscine wyverns in the same family as the shachihoko. Male makara are larger than females. Many villages use makara as mounts. When threatened, makara emit a blinding flash of energy from their mouths, stunning would be hunters.
Element: Light/Water/Dragon
Sea goats are marine invertivores that feed on crustaceans, polychaetes and molluscs. They have well-developed chemosensory organs which they use to find their prey.
While male sea goats are similar in size to females, they have longer horns and are more colorful in appearance while the females have shorter horns and are dull in color.
Referred Species: C. africanus, C. carteri, C. diutinus, C. elegans, C. eruciferus, C. felchi, C. fossanovum, C frazieri, C. guentheri, C. gustasoni, C. hierogyphus, C. humei, C. kempae, C. kranzi, C. latissimus, C. molossus, C. nirumbee, C. robustus, C. stewarti, C. szechuanensis, C. texanus, C. tunuensis
Status: Extinct
Time and Place: 252 to 55 million years ago, from the Induan of the Early Triassic to the Ypresian of the Eocene.
Ceratodus is known from the United States, Peru, Uruguay, Greenland, Svalbard, South Africa, Madagascar, Morocco, Libya, Mali, Niger, Egypt, Sudan, Saudi Arabia, France, Spain, Switzerland, Liechtenstein, Germany, England, Russia, India, Mongolia, Thailand, and Australia.
Physical Description: Ceratodus is... a lungfish. Most of the fossil remains are distinctively-shaped teeth. These teeth are multicusped and in life would be incorporated into a solid crushing surface with other tissues in the mouth. Externally it would have looked very much like the Queensland lungfish. In fact, it used to be considered a species of Ceratodus, until it was moved to the genus Neoceratodus in 1977. Ceratodontiform morphology has changed little in the intervening time. Look at a lungfish and you know what Ceratodus was like.
Diet: Ceratodus would have eaten fish, small amphibians, a variety of invertebrates, and possibly plant matter, much like its living relative.
Behavior: Ceratodus is probably best compared to a fallen log. It would have sat quietly at the bottom of calm waters, waiting for food to come on by. It was likely primarily nocturnal, and more mobile at night. As a lungfish, it would have been able to breathe air, and thus would be able to survive its habitat drying up. Going off its modern relatives, it may have been able to live for absurdly long periods of time if left alone - captive Queensland lungfish can and have reached their 90’s.
Ecosystem: Ceratodus fossils are known from pretty much everywhere. In the Triassic, Ceratodus is known from North America, Europe, western Asia, India, and Australia. Most Ceratodus-bearing habitats were marshlands or other calm freshwater environments. Other Ceratodus-bearing sites are marine, meaning the Ceratodus found there were probably washed out to sea. The seasonal wetlands Ceratodus probably favored were also frequented by sharks such as Hybodus and xenacanthids, ray-finned fish, temnospondyls, and phytosaurs. The exact species vary by location; in North America, Ceratodus lived alongside phytosaurs like Rutiodon and Smilosuchus, while in Eurasia temnospondyls such as Metoposaurus and Cyclotosaurus were more common. Of course, many land-living animals would have come by these rivers to drink, such as cynodonts, rhynchosaurs, pseudosuchians, and early dinosaurs. To go more in-depth would make this article three times as large as it currently is.
Other: There’s a town in Queensland called Ceratodus.
~ By Henry Thomas
Sources under the Cut
Case, E.C. 1921. A new species of Ceratodus from the Upper Triassic of western Texas. Occasional Papers of the Museum of Zoology, University of Michigan 101: 1-4.
Gunther, A.C.L.G. 1871. Description of Ceratodus, a genus of ganoid fishes, recently discovered in rivers of Queensland, Australia. Philosophical Transactions of the Royal Society 161: 511-571.
Kemp, A. 1993. Ceratodus diutinus, a new ceratodont from Cretaceous and Late Oligocene-medial Miocene deposits in Autralia. Journal of Paleontology 67 (5): 883-888.
Martin, M, Ingavat, R. 1982. First record of an upper Triassic ceratodontid (Dipnoi, Ceratodontiformes) in Thailand and its paleogeographical significance. Geobios 15 (1): 111-114.
Time and Place: 252 to 247 million years ago, from the Induan to the Olenekian of the Early Triassic.
Rebellatrix is only known from British Columbia.
Physical Description: Rebellatrix is a coelacanth like no other. Its body is a more elongate and slender than other coelacanths, and each fin (which, being a sarcopterygian, has a fleshy “limb” for the base) has a reduced rays. But its most distinctive feature is its tail. In living coelacanths, the caudal fin forms a broad, continuous shape. It is formed from three lobes: a large upper and lower lobe, and one tiny one in the middle at the tip of the tail. In Rebellatrix, however, the upper and lower lobes have greatly expanded, projecting far posteriorly and forming pointed shapes. This gives the tail a half-moon shape, similar to tuna or some sharks. The body was covered with ridged scales and bore a complex lateral line system. The head shape is unknown, but here we’ve restored it as pikelike based on its inferred ecology.
Diet: Rebellatrix was likely an active predator; its diet likely consisted of smaller fish.
Behavior: Rebellatrix was unique among coelacanths in being a fast-moving pursuit predator; the shape of the tail fin is similar to those of fast oceanic predators today. Also uniquely, the elements of the tail fin have fused. This would have led to a less flexible tail than modern coelacanths, who are lazier “lurk-and-lunge” predators that use every fin except the tail fin for most movement. Rebellatrix, by contrast, used its tail as the basis of sustained, rapid movement, and used the other fins to fine-tune its swimming.
Ecosystem: Rebellatrix was found in the Sulphur Mountain Formation of Canada. At the time, the area was a continental shelf. Based on how rare Rebellatrix is, it is likely that it lived in the open sea and only occasionally visited the area. In fact, few other species are known from the same localities, but these include the coelacanthimorph Belemnocerca and the ichthyosaur Utatsusaurus.
Other: Rebellatrix shows that, contrary to popular belief, coelacanths were not evolutionarily stagnant for over 300 million years - there was some evolutionary innovations along the line. And, along with Saurichthys, Rebellatrix represents other fish filling the “active pursuit predator” niche that was dominated by sharks before the Permian-Triassic Extinction.
~ By Henry Thomas
Source (there’s only one so no cut)
Wendruff, A.J., Wilson, M.V.H. 2012. A fork-tailed coelacanth, Rebellatrix divaricerca, gen. et sp. nov. (Actinistia, Rebellatricidae, fam. nov.), from the Lower Triassic of western Canada. Journal of Vertebrate Paleontology 32(3): 499-511.
[Image Description: a digital illustration of a group of coelacanths swimming under an archway with skulls carved on it, they are lit by red light. There are also rainbow lens flares coming from the lights]
Sarcopterygian fish (Holoptychius quebecensis) from the Devonian period (417-354 million years ago). This was an early lobe-finned bony fish, and a relative of Tiktaalik; the fishapod that used its limbs to walk out of water and onto land.
On display in 'Evolving Planet' at The Field Museum.
