#dipnoi

[herpsandbirds]

Australian Lungfish (Neoceratodus forsteri), family Neoceratodontidae, order Ceratodontiformes, class Dipnoi, Australia

ENDANGERED.

photograph by Bill Hawthorne

[mesozoicmarket]

A Cretaceous lungfish tooth plate of a Neoceratodus africanus or Ceratodus sp. from the Elrhaz Formation in Gadoufaoua, Niger. These giant Mesozoic lungfish would have been prey for genera like Suchomimus tenerensis and Sarcosuchus imperator.

[bestanimal]

Round 2 - Chordata - Dipnoi

(Sources - 1, 2, 3, 4)

Dipnoi is a class of Sarcopterygiian fish commonly called “lungfish”. While widely distributed since the Early Devonian, today only 6 species remain. They are the closest living relatives to tetrapods (amphibians, reptiles, and mammals).

Like other Sarcopterygiians, lungfish have lobed, bony fins and a well-developed internal skeleton. True to their name, they have a highly specialized respiratory system which includes lungs, subdivided into numerous smaller air sacs. Most extant lungfish species have two lungs, with the exception of the Australian Lungfish (Neoceratodus forsteri), which has only one. The Australian Lungfish can breathe through its gills without needing air from its lung, but in all other species the gills are too atrophied to allow for adequate gas exchange. Lungfish have unique dentition, bearing fan-shaped tooth plates called odontodes, which are used to crush hard shelled organisms. Some groups have ridges on these tooth plates that form occluding blades. They are omnivorous, feeding on fish, insects, crustaceans, worms, mollusks, amphibians, and plant matter. African and South American Lungfish are capable of surviving seasonal drying-out of their habitats by burrowing into mud and estivating throughout the dry season.

(own work)

How do you feel about Dipnoi? (Remember to vote for your favorite animal within this group, not how you feel about the group as a whole!)

One or more of my favorite animals is in Dipnoi

I love one or more of these animals

I like one or more of these animals

I am neutral about all of these animals

I dislike all of these animals

I hate all of these animals

Voting ended onDec 6, 2024

Propaganda under the cut:

The Australian Lungfish has existed in Australia for at least 100 million years, making it a true living fossil and one of the oldest living vertebrate genera on the planet. It is the most primitive surviving member of the ancient Dipnoi lineages.

The Marbled Lungfish's (Protopterus aethiopicus) genome contains 133 billion base pairs, making it the largest known genome of any vertebrate. The only organisms known to have more base pairs are the amoeboid Polychaos dubium and the flowering plant Paris japonica at 670 billion (possibly) and 150 billion, respectively.

The Spotted Lungfish (Protopterus dolloi) can aestivate on land by surrounding itself in a layer of dried mucus.

An Australian Lungfish named “Granddad” at the Shedd Aquarium in Chicago lived to be 109 years old, before he had to be euthanized due to an age-related decline in health. The current oldest Australian Lungfish is now “Methuselah”, who lives at the California Academy of Sciences, and is around 100 years old. Methuselah has been described as "mellow" by her keeper. She is also noted to like belly rubs, back rubs, and fresh figs.

Australian Lungfish are one of the cutest animals on the planet and I want a life-sized plushie/body pillow of one

[kataranah]

There is no such thing as a fish and on Neptune it’s raining diamonds.

These are facts that make the absurdity of this big old universe more clear.

This could be a comfort to me. It should stop me from taking myself too serious. It should encourage me in embracing the fullness and mysteries of life INCLUDING myself. I want it to be my “prescription for hope”.

I’m not there yet. But I truly am trying.

[animalids]

West African lungfish (Protopterus annectens)

Photo by Michel Gunther

[wtf-triassic]

Ceratodus

By Ripley Cook

Etymology: Horn tooth

First Described By: Agassiz, 1837

Classification: Biota, Archaea, Proteoarchaeota, Asgardarchaeota, Eukaryota, Neokaryota, Scotokaryota, Opimoda, Podiata, Amorphea, Obazoa, Opisthokonta, Holozoa, Filozoa, Choanozoa, Animalia, Eumetazoa, Parahoxozoa, Bilateria, Nephrozoa, Deuterostomia, Chordata, Olfactores, Vertebrata, Craniata, Gnathostomata, Eugnathostomata, Osteichthyes, Sarcopterygii, Rhipidistia, Dipnoi, Ceratodontiformes, Ceratodontidae

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.

http://www.paleobiodb.org

[just-call-me-ishmael]

Photoset 1 from the Melbourne Museum with @captain-amaezing! 

1. Cast of Inostrancevia, a Permian gorgonopsid and a relative of ours

2. A beautiful Banded Iron Formation with pyrite. My finger there for scale.

3. Phar Lap, the famous Australian racehorse. 

4. A paper-mache(!!!) model of the human body. If that wasn’t labor intensive enough, it opens up to show the internal organs. 

5. Neoceratodus forsteri, or the Queensland lungfish. One of the few surviving lungfish, this guy is truly a living fossil. 

6. The magnificent skull of Physeter macrocephalus, or the sperm whale. 

7. The skull of Janjucetus, a stem mysticete with teeth!

8. Aboriginal sculpture of my favorite marsupial, the tassie devil.

9. A quality rancho.

10. The arching skull of the pygmy blue whale, a subspecies, Balaenoptera musculus brevicauda. 

(Part 1) (Part 2)

[herpsandbirds]

This odd fish has 30 times as much DNA as humans—a new record for animals

Lacking key genes that control selfish bits of DNA, the South American lungfish’s genome just grew and grew.

A species of lungfish found in South America has claimed the title of the animal with the biggest genome sequenced so far. The DNA of Lepidosiren paradoxa comprises a staggering 91 billion chemical letters or “bases,” 30 times as many as the human genome, researchers report today in Nature. However, those 91 billion bases of DNA only contain about the same number of genes that humans have—roughly 20,000—with the rest consisting of noncoding, perhaps even “junk” DNA. By comparing this genome with those of other lungfishes, the researchers determined that L. paradoxa adds the equivalent of a human genome to its DNA every 10 million years...

Read more: https://www.science.org/content/article/odd-fish-has-30-times-much-dna-humans-new-record-animals