recursal/Fanatic-Fandom huggingface dataset:
Enhydrocyon

Credit: Mauricio Antón.

*Enhydrocyon* is an extinct genus of canid that lived during the Oligocene to the Early Miocene in North America.

## Description

*Enhydrocyon*'s dentition tells us that it led a hypercarnivorous or mesocarnivorous lifestyle. The shape of it's skull is close in shape to the modern otter's (*Enhydra*) skull; of which its name derives. *Enhydrocyon* was powerfully built and its jaw was like that of a jaguars. *Enhydrocyon* was the earliest adapted canine and was relatively large.

## References

https://en.wikipedia.org/wiki/Enhydrocyon
Gongpoquansaurus

Credit: Jack Wood.

*Gongpoquansaurus* is an extinct genus of basal Hadrosauroid that lived in China .

## Description

The name was proposed by Lü Junchang (1997) as *Probactrosaurus mazongshanensis*, but phylogenetic studies show a less derived position, opting for a new combination. The name "Gongpoquansaurus" was informally suggested and formally coined in a 2014 redescription. It is known from IVPP V.11333, a partial skull and postcrania from Mazongshan (which it is named after), Gansu Province, China. The individual is juvenile closely related to *Equijubus* and closer affiliated with other hadrosauroids than *Probactrosaurus*.

## References

* https://a-dinosaur-a-day.com/post/150229654885/gongpoquansaurus-mazongshanensis
* https://www.researchgate.net/publication/270571183\_Gongpoquansaurus\_mazongshanensis\_Lu\_1997\_comb\_nov\_Ornithischia\_Hadrosauroidea\_from\_the\_Early\_Cretaceous\_of\_Gansu\_Province\_northwestern\_China
Gillicus

*Gillicus* is an extinct genus of ray-finned fish that lived during the Late Cretaceous in North America.

## Description

*Gillicus* is known from many fossil specimens. *Gillicus* had numerous teeth that lined its jaws, which helped pin prey inside its mouth, to which it sucked in its prey by creating a small vortex. *Gillicus* may have also filter fed. *Gillicus* was a prey item of its much larger cousin, *Xiphactinus*. One specimen in particular, of a 13-foot-long *Xiphactinus* preserved with a *Gillicus* in its stomach collected by George F. Stenberg, shows this relationship. The current theory is that the thrashing of the *Gillicus* ruptured an organ, causing both to die and be rapidly covered in sediment. This fossil is held in the collections of the Sternberg Museum of Natural History, and is labelled as "Fish-Within-A-Fish".
Mantispa damzenogedanica

*Mantispa damzenogedanica* is an extinct species of mantidfly lacewing that lived in Russia during the Late Eocene.

## History

Viktor Baranov discovered a well-preserved insect specimen from Yantarny mine in Kaliningrad oblast, which was bought by private amber collector and paleoentomology supporter Jonas Damzen to alert researchers. They found it was very similar to *Mantispa*, but the rear wing venation and its genitalia are obscured by a film of verlummung, which made it enigmatic. However, it is likely a part of this genus, and was named in 2022 as *Mantispa? damzenogedanica*. The name is a combination of Jonas Damizen and "gedanicum", the Latin name referring to Gdańsk, Poland, where the specimen was deposited in the local museum. This is one of few lacewings in Baltic amber, and it is yet unknown why this is. The holotype is MG/B/1172.

## Paleoecology

*M. damzenogedanica* lived in the Middle-Late Eocene 38-33.9 million years ago, where the climate was warm and temperate. This temperature is perftect for modern lacewings, so it can be assumed that unsuitable climate accounts for rarity in the fossil record. Immense faunal turnovers from the K-PG mass extinction are hypothesized to have caused a decline of lacewing diversity due to a less conductive environment.

## References

* https://paleobiodb.org/classic/basicTaxonInfo?taxon\_no=450950
* https://phys.org/news/2022-03-million-year-old-baltic-amber-reveals-lacewing.html
Epieurycerus

Credit: paleozoobr.com.

*Epieurycerus* (also known as *Epieuryceros*) is an extinct genus of deer that lived in Argentina during the Quaternary.

## Description

*Epieurycerus* is just taller than a human, and is known by two spellings; *Epieurycerus* and *Epieuryceros*. *Epieurycerus* was made synonymous with *Blastocerus* in 1982.

## Paleoecology

*Epieurycerus* is a terrestrial grazer, and is known from three specimens from Argentina.

## References

https://paleobiodb.org/classic/basicTaxonInfo?taxon\_no=262022
Mapusaurus

Credit: Cisiopurple on DeviantArt.

*Mapusaurus* is an extinct genus of carcharodontosaurid theropod dinosaur that lived in Argentina during the Late Cretaceous.

## Description

*Mapusaurus* was close in size to *Giganotosaurus*, but some claim that isolate remains from *Mapusaurus* are larger than the latter. The Argentinian-Canadian Dinosaur Project team uncovered *Mapusaurus* from 1997-2001. It was then named by Rodolfo Coria and Phil Currie (2006) meaning "earth lizard" from the Mapuch word Mapu ("of the land"). It was closer related to *Giganotosaurus* than it was to *Carcharodontosaurus*.

## Paleobiology

Mapusaurus found in a bone bed with at least 7 individuals of many ontogimorphs. Coria and Currie (2006) speculate this could be long-term or a mass accumulation of individuals. Coria further states in a press-conference that they may be a family unit that may have worked together to take down immense prey such as the contemporaneous *Argentinosaurus*.

## References

* https://www.nhm.ac.uk/discover/dino-directory/mapusaurus.html
* https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0063409
* https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3655119/
* https://www.researchgate.net/publication/228655543\_A\_new\_carcharodontosaurid\_Dinosauria\_Theropoda\_from\_the\_Upper\_Cretaceous\_of\_Argentina
* https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3061882/
* https://link.springer.com/article/10.1007%2Fs12542-014-0251-3
* https://www.researchgate.net/publication/287905148\_Sedimentary\_paleoenvironments\_in\_the\_Upper\_Cretaceous\_Plottier\_Formation\_Neuquen\_Group\_Confluencia\_Neuquen
* https://www.researchgate.net/publication/241723727\_Middle\_Cretaceous\_microflora\_from\_the\_Huincul\_Formation\_Dinosaurian\_Beds\_in\_the\_Neuquen\_Basin\_Patagonia\_Argentina
* https://link.springer.com/article/10.1007/s12542-014-0251-3
* https://royalsocietypublishing.org/doi/10.1098/rsos.210923
* https://www.sciencedirect.com/science/article/abs/pii/S0895981112000831
* https://www.cambridge.org/core/journals/journal-of-paleontology/article/carcharodontosaurian-remains-dinosauria-theropoda-from-the-upper-jurassic-of-portugal/52DA60451B9984FBD24B2B4B2390A281
* https://www.mindat.org/taxon-4822971.html
* https://dinonews.net/rubriq/docs/2006\_coria\_mapusaurus.pdf
* https://dinosaurpictures.org/Mapusaurus-pictures
* https://www.reuters.com/article/us-science-dinosaur-idUSKCN0ZT2BH
* http://lveho.ivpp.cas.cn/kycg/lw/201404/P020140409593112402367.pdf
* https://palaeo-electronica.org/content/2017/2073-theropod-trackway-at-las-hoyas
* https://doi.org/10.1016%2Fj.cretres.2019.104319
Keuppia

*Keuppia* is an extinct genus of octopus that lived in Asia during the Late Cretaceous.

## Description

*Keuppia* is known from fossils that preserve soft tissues, including internal organs and an outline of the body plan. *Keuppia* has a gladius vestige, showing the transition from squid to octopus. Keuppia is often found in deposits alongside *Styletoctopus*. The inner shell is divided in two, which would soon transform into lateralized stylets, which is another basal trait.
La Colonia Chelid

Crania and mandible, MPEF-PV 10570.

The La Colonia Chelid is an unnamed genus of Chelidae turtles that lived in Argentina during the Late Cretaceous.

## History

It is the first occurrence of chelids in the La Colonia Formation not in Hydromedusinae, and is much rarer than highly-decorated taxa from the Late Cretaceous, which has interesting applications in chelid evolutionary biology.

## Description

This taxon is known from a skull, a mandible, and postcrania; MPEF-PV 10570 (skull and mandible) and MPEF-PV 10830 (postcrania including shell, parts of the girdle and limbs). It was discovered from the Norte de Cerro Bayo 2 locality of the La Colonia Formation. The skull only lacks the posterolateral portion of the basioccipital, and the mandible is complete. Of the `preserved shell parts are the nuchal, periphericals and neurals, as well as the pectoral and pectorals and the long bones, phalanges and metapods of the limbs. It is a very large species, with a shell about 70 centimeters long that apparently lacks ornamentation. Along the skull is anteroposterior elongation of over 10 centimeters. The processus trochlearis pterygoidei is well-developed. The marked cheek and temporal emargination are defined and nearly absent, respectively. Separating both is a posterior bridge is more robust than extant chelids.

## References

* https://en.wikipedia.org/wiki/La\_Colonia\_Formation
* https://www.sciencedirect.com/science/article/abs/pii/S0195667114002225
Kaijutitan

Credit: CisioPurple on DeviantArt.

*Kaijutitan* is an extinct genus of titanosaur that lived in Argentina during the Late Cretaceous.

## Description

*Kaijutitan* is known from the Sierra Barrosa Formation, Neuquén Province, Argentina. Kaiju refers to a subgenre of Japanese movie monsters (most famous: Godzilla, King Kong, Mothra, etc), and is a reference to *Kaijutitan*'s immense size.

Wang et al. (2021) recovers the following cladogram:

## References

1. ↑ https://en.wikipedia.org/wiki/Kaiju
2. ↑ https://www.sciencedirect.com/science/article/abs/pii/S0195667118304816?via%3Dihub
3. ↑ https://www.nature.com/articles/s41598-021-94273-7
La Boucharde taxon

The La Boucharde taxon is an unnamed genus of majungasaurine abelisaurid that lived in France during the Late Cretaceous.

## Description

The taxon is known from a tibia bone, measuring 400 mm long recovered from the Campanian-aged Begudian beds of France. No specimen ID is known, so it is possible this taxon was sunk into another at some point.

## Classification

Filippe et al. (2016) recovered the taxon as the sister to *Arcovenator*, these two taxa, along with possibly the Pourcieux Abelisaurid may represent a distinct lineage of Abelisaurids of France.

## References

* https://en.wikipedia.org/wiki/Arcovenator
* https://www.theropoddatabase.com/Ceratosauria.htm
* https://www.sciencedirect.com/science/article/abs/pii/S075339691300089X?via%3Dihub
Ichthyodectes

Credit: Wsnyder on DeviantArt.

*Ichthyodectes* is an extinct genus of Ichthyodectid fish that lived in Canada and the United States during the Late Cretaceous.

## Description

*I. ctenodon* is 4 meters long, and lived in the Western Interior Seaway in North America, and was closely related to *Xiphactinus audax*. Like many other ichthyodectids, *Ichthyodectes* is a presumed pursuit predator of smaller animals, including other fish. As the species epithet suggests, *I. ctenodon* had small uniform teeth, it's smaller relative, *I. arcuatus* sharing this. The fish may have sucked prey into their jaws.

## Species

* *I. acanthicus*
* *I. anaides*
* *I. arcuatus*
* *I. cruentus*
* *I. ctenodon*
* *I. elegans*
* *I. goodeanus*
* *I. hamatus*
* *I. libanicus*
* *I. minor*
* *I. multidentatus*
* *I. parvus*
* *I. perniciosus*
* *I. prognathus*
* *I. tenuidens*

## References

https://en.wikipedia.org/wiki/Ichthyodectes
Machairoceratops

Before formal naming or identification, this organism was known as the following on this wiki:
**Star Seep Centrosaur**, **Wahweep Centrosaur B** and **UMHN VP 20550**

## Statistics

### Diet

Herbivorous

*Machairoceratops* Is a genus of Centrosaurine Ceratopsid dinosaur that lived in southern Utah during the Late Cretaceous.

## Description

the taxon was recovered at the upper part of the Star Seep member of the Wahweap Formation, named in 2016 by Eric K. Lund, Patrick M. O’Connor, Mark A. Loewen and Zubair A. Jinnah. The persevered elements, UMHN VP 20550, included 2 elongate horn cores over the eyes, a partial braincase that is somewhat deformed, the left jugal, the left squamosal, and a mostly complete parietal adorned with ornamentation. The preserved elements indicate that it is likely a very close relative of *Diabloceratops* and the Pilot Knoll Centrosaur, with all material collected in association.

The genus derives from Greek machairis, meaning "bent sword", referencing the unique frill ornamentation (including two forward curving horns at the uppermost section), and Latinized Greek ceratops, meaning "horned-face", a common suffix for ceratopsian genera. The specific epithet name, *cronusi*, refers to Cronus, a Greek god who deposes his father, Uranus, by using a sickle or scythe to castrate him. This is based on mythology, often depicted wielding a curved, bladed weapon.

## Classification

Lund et al. (2016) tested *Machairoceratops*' placement in Centrosaurinae by using maximum parsimony and Bayesian phylogenetic species-level analyses. Maximum parsimony showed a large polytomy basalmost of centrosaurinae, with only Centrosaurini, the majority of Pachyrhinosaurini (including *Einiosaurus*, *Wendiceratops* and Pachyrostra), and the *Avaceratops*-*Nasutoceratops* clade being resolved. The Bayesian showed a fully-resolved topology, depicted below:

The cladogram below is the conclusions by Chiba et al. (2017):

## References

* https://www.academia.edu/32383050
* https://en.wikipedia.org/wiki/Machairoceratops
Issi

*Issi* is an extinct genus of plateosaurid dinosaur that lived in Greenland during the Late Triassic.

## History

*Issi* was recovered by Harvard paleontologists from the Malmros Klint Formation during the summer of 1991. There, it was deposited into the Natural History Museum of Denmark alongside many other undescribed specimens. It was excavated in cold conditions, from which it was named after.

## Description

*Issi* is known from holotype NHMD 164741, a subadult, and paratype NHMD 164758, a late-stage juvenile. These are two articulated mostly complete skulls. The genus is diagnosed by a small foramen on the medial of the premaxilla, an anteroposteriorly-elongate dorsoposterior process on the squamosal, a high quadrate compared to the rostrum and a developed posterodorsal process on the articular. Though no size estimate was given since both were immature, the skull is ~190 millimeters long, and so it has an estimated rough length of 5 meters.

## Classification

The holotype was first assigned to *Plateosaurus engelhardti* (=*P. trossingensis*) by Jenkins et al. (1994). However, Victor Beccari, Octávio Mateus, Oliver Wings, Jesper Milàn and Lars B. Clemmensen (2021) reassigned it to a new genus and species, translating to "cold bone" (*Issi*="cold", *saneeq*="bone") in a local Inuit language. It is very similar to *Unaysaurus* and *Macrocollum*. It seems to be intermediary of Brazilian species and *Plateosaurus*. Thus, it is recovered as a plateosaurid via a new phylogenetic analysis:

## Paleoecology

*Issi* is the first sauropodomorph discovered to have reached latitudes over 40° North. It is from the 'Iron Cake' site, Fleming Fjord Group, Malmros Klint Formation of the Late Norian. Most of the formation is exposed from a cliff with the typical thickness of 125 meters. Fish such as *Ceratodus tenuensis*, theropods, temnospondyls, turtles, aetosaurs, phytosaurs and pterosaurs are present. Early mammaliaform teeth and bony fragments are also reported. This specific group *Issi* is a part of was deposited 220-209 million years ago. Theropod ichnofossils such as footprints are also known.

## References

* https://www.researchgate.net/figure/Footprint-of-theropod-dinosaur-from-the-Malmros-Klint-Member-of-Liasryggen-Photo-by-G\_fig2\_269411243
* https://www.mdpi.com/1424-2818/13/11/561
Lythronax

Credit: Andrey Atuchin.

*Lythronax* is an extinct genus of tyrannosaurid dinosaur that lived in North America during the Late Cretaceous.

## Description

*Lythronax* is a large-bodied tyrannosaur that had short forelimbs, strong legs, a long tail, wide jaws, and a constricted snout. *Lythronax* had pronounced bony ridges above its eyes, and relatively small crests reaching down the skull. Compared to *Tyrannosaurus*, the back of *Lythronax'*s head was broad, but slender near the snout tip. *Lythronax* has two fingers on each forelimb, which sat but the side of its body uselessly.

*Lythronax'*s teeth are closely compared to serrated bananas. *Lythronax* may have possessed lips on its upper jaw, and is sometimes depicted with a light covering of feathers.

## Paleoecology

*Lythronax* lived in the Wahweap Formation in the Late Cretaceous and was the apex predator of its ecosystem. *Lythronax* lived when the Western Interior Seaway was at its greatest expanse, and the land was dominated by floodplains, lakes and rivers. Evidence of a wet season is present due to the abundance of sediment and well preserved fossils. *Lythronax* lived with the hadrosaurs *Acristavus*, *Adelolophus*, a ceratopsian; *Diabloceratops*, and an abundance of fish, sharks and rays.The Wahweap Formation also has several unnamed pachycephalosaurs and ankylosaurs.
Kootenichela

*Kootenichela* is an extinct genus of arthropod that lived in Canada during the Middle Cambrian.

## Description

*Kootenichela*'s body is 29 segments long, all similar in size and shape. The animals had has large stalk eyes and a structure resembling an antenna. The limbs attached at the trunk are sclerotized poorly. Of *Kootenichela*'s appendages, most prominent is the scissor-like spinose cephalic limbs. *Kootenichela* appears to be a sister taxa to *Worthenella*, based on cladistic analysis. *Kootenichela* has been proposed to be a chimera by other scientists.

## Etymology

*Kootenichela* means "Kooteni claw/scissors". This name is a reference to the film Edward Scissorhands, of which the first half of the name is a reference to. The species name "*deppi*" is a reference to Johnny Depp, who plays Scissorhands in the film. David Legg, discoverer of *Kootenichela* had this to say:

—David Legg

## References

https://en.wikipedia.org/wiki/Kootenichela
MCT 2670-LE

MCT 2670-LE is an unnamed genus of carcharodontosaurian theropod that lived in Brazil during the Late Jurassic.

## Description

MCT 2670-LE is a middle distal caudal vertebra assigned to a theropod, excavated in 1961 by Ignacio Machado Brito in mostly Aliança Formation strata, but was attributed to the Sergi Formation due to the rock matrix. This would make it the first archosaur from this unite. Since it is shaped like a hourglass and has a deep, narrow central groove, it was assigned to carcharodontosauria. This may provide insight on their paleogeographic distribution before the South American-African break-up and theropod faunal turnover during the J-K transition in Brazil.

## References

https://www.scielo.br/j/aabc/a/7bvvDZNDTwCxTvZWcCjSLmF/?lang=en#
Laramie polyglyphanodont

UCM 42164

The Laramie polyglyphanodont is an unnamed genus of polyglyphanodont lizard that lived in Colorado during the Late Cretaceous.

## Description

The presence of lizards in the Laramie formation was first reported by O.C. Marsh in 1892. In 2012, Longrich, Bhullar, and Gauthier noted specimen UCMP 42164, a dentary, likely belonged to a new genus of lizards. The Laramie pologlyphanodont lived during the Maastrichtian.

## References

* https://archive.org/details/b2230552x
* https://www.researchgate.net/publication/233909499\_Mass\_extinction\_of\_lizards\_and\_snakes\_at\_the\_Cretaceous-Paleogene\_boundary
Hydrochoerus

This page is about a genus that contains extinct and extant species; species marked with † are extinct.

## Hydrochoerus

Hydrochoerus hydrochaeris. Credit: Rutpratheep Nilpechr.

## Statistics

### Diet

Herbivorous

*Hydrochoerus*, capybaras, is a genus of Caviid rodents that have lived in the Americas since the Pliocene.

## Species

* *H. hydrochaeris* (common/greater capybara)
* *H. isthmius* (lesser capybara)
* †*H. ballesterensis*
* †*H. hesperotiganites*
* †*H. gaylordi*

### Reassigned Species

* †*H. holmesi*
* †*H. pickneyi*

## References

1. ↑ https://en.wikipedia.org/wiki/Hydrochoerus
KMSP-100117

Comparison of the tooth (right, attached to matrix) and a rendering of a complete ceratopsid tooth (left, placement marked with red)

## Statistics

### Diet

Herbivorous

KMSP-100117 is an indeterminate genus of ceratopsid dinosaur that lived in Japan during the Late Cretaceous.

## History

The tooth was discovered in the Imuta Formation, Shimokoshikishima Island, Japan and reported on in 2013, but only published in 2016. It is the first proper Ceratopsidae from Japan, and may be the inspiration towards the fictional "Mihunekisaurus". It is known from the Campanian-Maastrichtian.

## Description

The specimen was identified as a fragment of the bifurcated tooth root of a ceratopsid dinosaur. It was suggested that, including known Japanese dinosaurian diversity, Shimokoshikishima Island had an even more well represented and developed fauna than assumed, proving important in the larger scheme. The specimen is 8.6 millimeters high, 12.1 long and 3.7 thick.

## References

* https://www.kahaku.go.jp/research/publication/geology/download/42/BNMNS\_C42\_29-34.pdf
* https://www.nhregister.com/connecticut/article/First-Japanese-ceratopsian-fossil-found-11418357.php
Krokolithes

*Krokolithes* is an extinct oogenus of crocodile egg that lived in Portugal during the Jurassic.

## Description

Along with *Suchoolithus* of which it was found by, *Krokolithes* are small, and some of the oldest known crocodylian eggs.

## References

* https://en.wikipedia.org/wiki/Krokolithes

* https://en.wikipedia.org/wiki/Suchoolithus
Kataigidodon

*Kataigidodon* is an extinct genus of eucynodont that lived in North America during the Late Triassic.

## Description

*Kataigidodon* has large mental foramen, which is anteroposteriorly longer than its tail. The region opens at the lateral side of the first and second postcanines. The mental foramen is located at the anterior end of the lateral fossa. *Kataigidodon* possesses distinct, small and circular foramen, which is unlike other eucynodonts. This feature is most alike to those of *Boreogomphodon* and *Arctotraversodon*. The lateral dentary is covered in numerous tiny pits, which means the individual was immature at death.

## References

https://en.wikipedia.org/wiki/Kataigidodon
Megapiranha

This article does not meet the standards set by the Prehistoric wiki Manual of Style. Please edit it.

## Statistics

### Diet

Omnivorous?

*Megapiranha* is an extinct genus of ray-finned fish that lived in Argentina during the Late Miocene.

## Description

*Megapiranha's* bite is estimate at a whopping 1,240–4,749 Newtons. *Megapiranha* lived in South American river basins and was much larger than modern species. The holotype are premaxillae and a zigzag tooth row, with a double tooth row in pacus rather than modern piranhas. This, however, makes sense, as *Megapiranha* is a transitional form. This suggests the double tooth row may have rearranged to fit a single row during piranha evolution. 7 premaxillary teeth are present, with the first 4 arranged in a shallow zig-zag row, with the 3rd tooth shaped similarly to the 4th and 5th. It is large, triangular with unicuspid crowns with serrated edges. Parsimony analysis shows it is sister to the piranha clade. This is supported by 2 synapomorphies; triangular teeth in the labial view with well-developed serrated edges and serrations along both cutting edges.

## References

* https://en.wikipedia.org/wiki/Megapiranha
* https://www.angelfire.com/biz/piranha038/megapiranha\_paranensis.html
Meraxes

*Meraxes*, previously called the "Campinas carcharodontosaurid", is an extinct genus of gigantosaurinin carcharosaurid theropod dinosaur that lived in Patagonia during the Late Cretaceous.

## History

The holotype, MMCh-PV 65, was discoveredin 2012 and called the "Campinas carcharodontosaurid" before publication. It is one of the most complete carcharodontosaurs from South America, preserving a skull, complete fore- and hindlimbs, parts of the neck and torso, the pelvis and over half of the tail. Canale et al. (2022) named it after Meraxes, a fictional dragon from *A Song of Ice and Fire*, and with *gigas* indicating great size.

## Description

The forelimbs are considerable to derived tyrannosaurids, suggesting convergent evolution. Osteohistology suggests an age of up to 53 years at death, making it one of the oldest-living known non-avian dinosaurs. It had slower growth than tyrannosaurids that did not cease after maturity. Using this, most carcharodontosaurids reached maturity from 30-40 years. The reconstructed cranium recovers a length of 4 feet (127 centimeters) or 1.27 meters. In the press, it was compared to a gargoyle based on the rugose facial ornamentation. The teeth average 15 centimeters in length. It is diagnosed as having: two antorbital openings, a jugal stepping along the caudal of the postorbital process, a low and rounded lateral horn on the squamosal process, rounded projections along the dorsal margin of the lacrimal, deep and rounded fossa on the lateral of the quadratojugal, almost completel coossified sacral neural spines, complex hyposphene-hypantrum articulations on the anterior causal, an internal tuberosity separated by the humeral head by a cleft and an ovoid fossa at the anteroproximal and a 2nd pedal claw that is very large and almost twice the length of the digit IV ungual.

## Classification

Canale et al. (2022) find it to be the earliest-diverging member of Gigantosaurini:

## Paleoecology

*Meraxes* is known from the Huincul Formation, 13 meters above the Candeleros Formation in Las Campanas Canyon, Villa El Chocón, Neuquén Province, Patagonia, Argentina. It lived with dinosaurs such as *Huinculsaurus*, *Mapusaurus*, *Argentinosaurus*, *Choconsaurus*, *Cathartesaura*, *Limaysaurus*, *Gualicho*, *Aoniraptor*, *Skorpiovenator*, *Tralkasaurus*, *Ilokelesia*, *Overoraptor*, iguanodonts, abelisaurids and hadrosaurids.

## References

* https://en.wikipedia.org/wiki/Meraxes\_gigas
* https://www.cell.com/current-biology/fulltext/S0960-9822(22)00860-0?\_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982222008600%3Fshowall%3Dtrue
* https://www.reuters.com/lifestyle/science/argentine-gargoyle-shows-how-huge-predatory-dinosaurs-evolved-2022-07-07/
Irisosaurus

Irisosaurus is a naked genus of sauropodomorph that lived in China during the Early Jurassic.

## Description

Irisosaurus's skeleton shows multiple traits which are not unique. The genus is distinguished by large depression in the neurovascular foramen of the perinarial fossa. The premaxillary ramus on the maxilla is taller than it is long before the nasal process. The proximal half of metacarpal five is very asymmetrical.

Irisosaurus is a sister taxon to *Mussaurus*. However, it lacks a ZooBank, so it is a nomen nudum.

## Notable Specimens

* CVEB 21901: The holotype of Irisosaurus, consisting of metacarpals, several other postcranial elements and a partial skull.

## References

https://en.wikipedia.org/wiki/Irisosaurus
Maiasaura

Credit: Connor Ashbridge on the Wikimedia Commons.

*Maiasaura* is an extinct genus of hadrosaurid dinosaur that lived during the Late Cretaceous in Montana.

## History

*Maiasaura* is derived from the Greek μαία, the female variation of the Latin 'saur' meaning lizard or reptile. The name means 'good mother lizard' or 'good mother reptile' in its entirety.

## Description

*Maiasaura* had a flat beak, with thick nasal cavities. Males had a small spiky crest above their eyes, possibly for head butting competitions for females. *Maiasaura* was capable of standing in both bipedal and quadrupedal. Studies on the feet show that juveniles used a bipedal gait, and switched to a quadrupedal gait as they grew older. *Maiasaura* had no defense to their predators, lived inland, with herds of up to 10,000 individuals.

## Paleoecology

*Maiasaura* lived in Montana during the Late Cretaceous. Individuals lived in massive herds, that laid eggs once every month. *Maiasaura* cared for their young. Males bore a head crest for headbutting competitions, though had no defenses against predators.

A specimen auctioned off by Heritage Auctions, labelled as M. sp., is stated to be from the Hell Creek Formation. The specimen was inferred to be closer to but earlier than *M. peeblesorum*; however, *Maiasaura* lived millions of years before the Hell Creek fauna, so this must be untrue. The skull and jaw is in good condition with all teeth present and preserved in the upper jaw. The skull, after preparation, is reportedly 25 inches long. The braincase was also found, 5.5 inches long, with intact large, round olfactory lobes. It was found by a fossil collector whose daughter located a strange object, which turned out to be the skull. It was found disarticulated, the braincase partially embedded in rock. However, it is unlikely *Maiasaura* are present in Hell Creek. Some have noted a majority of the skull looks restored, with the presumed fossil parts assumed to be lambeosaurine, possibly of the Hell Creek lambeosaur. It may also be an amateur mistake or a lie used by the auction house used because Hell Creek is a popular geologic formation. Nonetheless, the skull was sold on September 28, 2014.

## Classification

Maiasaura classification per Horner et al., 2004 (top) and Gates and Sampson, 2007 (bottom).

## References

* https://en.wikipedia.org/wiki/Maiasaura
* https://twitter.com/BradtheCurator/status/1450862775744487427
* https://fineart.ha.com/itm/dinosauria/skulls/dinosaur-skull-with-incredible-brain-cast-maiasaura-spcretaceous-hell-creek/a/5192-73257.s
* https://archive.org/details/g.s.paul2016theprincetonfieldguidetodinosaurs/page/n258/mode/1up
Inachus

This page is about a genus that contains extinct and extant species; species marked with † are extinct.

## Statistics

### Diet

Carnivorous

*Inachus* is a genus of crab that lives in Africa, North America and Eurasia since the Miocene.

## Species

* *I. aguiarii*
* *I. angolensis*
* *I. biceps*
* *I. communissimus*
* *I. complectens*
* *I. dorsettensis*
* *I. grallator*
* *I. guentheri*
* *I. leptochirus*
* *I. mauritanicus*
* *I. nanus*
* *I. phalangium*
* *I. thoracicus*
* *†I. eocenicus*
* *†I. lethaeus*
* *†I. tuberculatus*

## References

* https://en.wikipedia.org/wiki/Inachus\_(genus)
* https://paleobiodb.org/classic/basicTaxonInfo?taxon\_no=22492
Leptolepides

*Leptolepides* was a primitive bony fish that lived in Germany during the Early Jurassic.

## Description

*Leptolepides* is a standard bony fish, with a slender body and fins and a gaping mouth. *Leptolepides* swam in large shoals and was very agile in shallow bodies of water.

## Reference

* https://en.wikipedia.org/wiki/Leptolepides
* Dorling Kindersley Encyclopedia of Dinosaurs and Prehistoric Life, p. 50
Julieraptor

Reconstructed Skeleton. Credit: Black Hills Institute.

"Julieraptor" is an informally named genus of dromaeosaurid theropod that lived in Montana during the Late Cretaceous.

## History

"Julieraptor" was discovered and prepared by the Black Hills Institute of Geological Research in 2010. The specimen was found in the Judith River Formation in Phillips County, Montana. It will be permanently housed in the Royal Ontario Museum in Toronto.

## Description

The proposed holotype of "Julieraptor" is the most complete dromaeosaurid found in North America. It was about the same size as a turkey (*Meleagris gallopavo*).

## Paleoecology

"Julieraptor" lived in the Judith River formation, dated to 75 million years ago during the Campanian stage of the Late Cretaceous.  It lived alongside numerous dinosaurs such as *Mercuriceratops*, *Zuul*, *Daspletosaurus*, and *Hesperornis*, as well as turtles, lizards, and crocodilians including *Deinosuchus*.

## References

1. ↑ 1.0 1.1 1.2 1.3 http://www.bhigr.com/store/product.php?productid=679&cat=53&page=1
2. ↑ https://en.wikipedia.org/wiki/Judith\_River\_Formation
Macrocheira yabei

*Macrocheira yabei* is an extinct species of crab that lived in Japan during the Miocene.

## Description

The type was recovered from locality IGPS loc. no. N-5, being the only fossil site where *M. yabei* has been collected.

## References

* https://paleobiodb.org/classic/basicTaxonInfo?taxon\_no=223583
* https://www.jstage.jst.go.jp/article/rcustacea/2/0/2\_KJ00003289224/\_article/-char/ja/
LH-02-01

LH-02-01 is an unnamed genus of Ornithomimosaur that lived in China during the Late Cretaceous.

## Description

LH-02-01 is known from a complete pelvic girdle, 5 sacral vertebrae and 1 caudal vertebra, all in articulation. Only *Shenzhousarus,* *Archaeornithomimus asiaticus, Gallimimus* are known to posses 5 sacral vertebrae rather than six. "{The 2nd and 3rd] ventral surfaces are flattened, but bear anteroposteriorly extending sulci, which become gradually shallower posteriorly" which has only been found in *Archaeornithomimus* and the 4th sacral of *Sinornithomimus.* "The well-preserved neural spines of the third and fourth sacrals are anteroposteriorly expanded and fused together, forming a continuous narrow plate" which is a condition similar to Deinocheirids but diffferent that *Gallimimus*, *Rativates,* and the Bisskety Ornithomimosaur. "The lateral surface of the caudal centrum is smooth, and there is no sign of pneumatization. The posterior articular surface is flat but rugose, and subquadrangular. The ventral surface is also flat" Which is distinctly different than the caudals of *Archaeornithomimus.* Several other features of the skeleton distinguish it further than any known Ornithomimosaur; however, Xi et. al. didn't give this taxon a name because, "The pelvic elements of LH-02-01 show a suite of anatomical features not seen in any other known ornithomimosaurian pelvic material. Given the fragmentary nature of LH-02-01 and the lack of discernible autapomorphies, however, we refrain from erecting a new taxon based on this incomplete specimen."

## Classification

This phylogeny was recovered by Xi et. al. (2022):

## References

* Yao Xi, Corwin Sullivan, Qingwei Tan, Xing Xu, New ornithomimosaurian (Dinosauria: Theropoda) pelvis from the Upper Cretaceous Erlian Formation of Nei Mongol, north China, Cretaceous Research, 2022, 105234, ISSN 0195-6671, https://doi.org/10.1016/j.cretres.2022.105234. (https://www.sciencedirect.com/science/article/pii/S0195667122000982)
Marmarospondylus

Credit: Miracusaurs on the Wikimedia Commons.

*Marmarospondylus* is a dubious genus of sauropod that lived in England during the Middle Jurassic.

## History

*Marmarospondylus* was originally published as a species of the dubious Late Jurassic genus: *Bothriospondylus*. The two dubious genera have been proven to be different. Recent papers dub *Marmarospondylus* as a dubious genus in macronaria.

## Notable Specimens

* NHMUK R.22428: The holotype of *Marmarospondylus*, consisting of a dorsal vertebrae.

## Reference

https://en.wikipedia.org/wiki/Marmarospondylus
Labrador duck

## Camptorhynchus

Museum diagram.

*Camptorhynchus*, or Labrador Duck is an extinct genus of duck that went extinct sometime after 1878.

## Description

Labrador duck is known for it diet, small molluscs and its flattened leathery bill used for combing through sand. Labrador Duck males were considerably more large and colourful then females.

## References

https://en.wikipedia.org/wiki/Labrador\_duck
Leptocyon

*Leptocyon* is an extinct genus of canid that lived in North America from the Oligocene to the Micene.

## Description

*Leptocyon* resembled that of a fox, and was likely omnivorous. *Leptocyon*'s bite was powerful, built for killing and snatching small, nimble animals. *L. delicatus* is one of the smallest canines known in the fossil record.

## Species

* *L. delicatus*
* *L. gregorii*
* *L. vafer*
* *L. vulpinus*
Messelopython

*Messelopython* is an extinct genus of python that lived in Germany during the Middle Eocene.

## Description

*Messelopython* is known as one of the oldest pythons, from a single articulated skeleton that is mostly complete from the Messel Pit (of which it is named), Germany. The species epithet is after Eberhard "Dino" Frey, an individual prominent in handling illegal fossils. Most pythons are not known in Europe, as European pythonids disappear in the fossil record, which shows they evolved in Europe and expanded outwards. European pythons reappear in our records sometime during the Miocene, likely due to climate. Modern pythons usually do not live with relatives, however *Messelopython* lived with *Eoconstrictor*, and likely competed with one-another.

## References

* https://phys.org/news/2020-12-world-earliest-python-million-year-old-fossil.html?deviceType=desktop
* http://www.sci-news.com/paleontology/messelopython-freyi-09168.html↑ https://www.smithsonianmag.com/smart-news/oldest-ever-python-fossil-found-europe-180976649/↑ https://scitechdaily.com/worlds-oldest-python-found-in-messel-pit/
Lusovenator

Credit: Gabriel Ugueto.

*Lusovenator* is an extinct genus of carcharodontosaurian that lived in Portugal during the Late Jurassic.

## Classification

*Lusovenator* is the oldest carcharodontosaurian from Laurasia, and is known from a juvenile postcranial skeleton. *Lusovenator* supports a theory that the clade Carcharodontosauria and the family Carcharodontosauridae radiated outwards before the Cretaceous even began. *Lusovenator* diversifies medium-to-large bodied coelurosaurids during the Late Jurassic on the Iberian Peninsula. More evidence will need to be uncovered to point towards carcharodontosaurids first emerging in North America's Morrison Formation.

## Description

*Lusovenator* has a bulky body, shark-like teeth, large clawed arms and a strong tail. *Lusovenator* lacks a crest above its eyes.

The genus itself is distinguished by three unique features:

1. Big recesses on the anterior dorsal vertebrae in the neural arch.
2. Continuous and developed longitudinal laminae, running from the tip of the prezygapophyses, down to the distal terminate of the prezygapophyses on the mid-caudal vertebrae.
3. The supraacetabular crest on the ilium forms a notable ventrolaterally projecting shelf.

## References

1. ↑ https://www.tandfonline.com/doi/10.1080/02724634.2020.1768106
2. ↑ https://en.wikipedia.org/wiki/Lusovenator
Leshansaurus

Credit: Cisiopurple on DeviantArt.

*Leshansaurus* is an extinct genus of theropod dinosaur that lived in China during the Late Jurassic.

## Description

The femur is 62 centimeters long anf the tibia is 52 centimeters long. Autapomorphies include: a sharp central ridge on the supraoccipital, elongate frontals 2.86x as long as their width, slender basipterygoid projections on the basisphenoid, the lower braincase having a bone, a horseshoe-shaped in cross section atlas intercentrum, slender diapophyses, thin dorsal and sacral spines, a clear keel at the bottom of the sacrals and an ilium with an inner side that bears a ridge along the edge of the joint. Li et al. placed it in Sinraptoridae, but did not provide a cladogram. Matthew Carrano (2012) found it as an afrovenatorine sister to *Piveteausaurus*.

## References

* https://www.researchgate.net/publication/291852089\_A\_new\_carnosaur\_from\_the\_Late\_Jurassic\_of\_Qianwei\_Sichuan\_China
* https://www.researchgate.net/publication/230808558\_The\_phylogeny\_of\_Tetanurae\_Dinosauria\_Theropoda
Latenivenatrix

Credit: Fred Wierum.

*Latenivenatrix* is an extinct genus of troodontid dinosaur that lived in Canada during the Late Cretaceous.

## History

The holotype of *Latenivenatrix* is CMN 12340, originally described by Dale Alan Russell (1969) and referred to *Stenonychosaurus* and then to *Troodon* in 1987. Irene Vanderloh had collected it in 1968 in the Dinosaur Park Formation, preserving frontals, prietals, postorbital, basioccpital and basisphenoid, four vertebrae, four ribs, chevrons, gastralia, a fairly complete forelimb and incomplete hindlimbs. Three more specimens from the same locality were reffered. UALVP 55804 represents a partial pelvis, TMP 1982.019.0023, a partial skull and TMP 1992.036.575, a right dentary and left metatarsals. *Latenivenatrix* is distinguished from *Stenonychosaurus* due to frontal and metatarsal III structure. Referred remains include CMN 12340, TMP 1979.008.0001, TMP 1980.016.1478, TMP 1986.036.0004, and UALVP 55285 and TMP 1997.133.0008, a metatarsal III.

## Description

*Latenivenatrix* has a skull 45 centimeters (18 inches) long, with an estimated 3-3.5 meters (9.8-11.5 feet) long, being the largest troodontid. *Latenivenatrix* is distinguished based on the pubis having a retroverted 17° angle, an anteriorly-curved pubic shaft, a large muscle scar at the lateral surface of the pubic shaft, a pubic boot that is slightly proximal (seen in *Hesperonychus*). Other features that separate *Latenivenatrix* from derived troodontids (especially *Stenonychosaurus*) is a triangular form with a deep groove in the frontonasal contact surface on each frontal and a metatarsal III with a concave anterior surface. This is absent in *Saurornithoides*, *Talos*, *Urbacodon* and *Stenonychosaurus*, but is present in *Philovenator*, but not verifiable in a few species.

## Classification

Latenivenatrix is a derived troodontid, part of the newer Troodontinae, likely related to coeval Asian forms, such as *Linhevenator* and *Philovenator*.

## Paleobiology

*Latenivenatrix* was the largest troodontid, and was likely semi-omnivorous, bipedal and lost the traits of primitive flyers. It probably had a distinct niche from *Stenonychosaurus*, which coexisted with it.

### Paleopathology

TMP 79.8.1, a parietal, bears a pthological aperture. Phil Currie (1985) hypothesized this was caused by a cyst, but Tank and Rothschild (1999) thought it was a bite wound. One specimen, a hatchling, may have suffered from a congenital defect, which resulted in the front of the jaw abnormally twisting.

## References

* https://cdnsciencepub.com/doi/10.1139/cjes-2017-0031
* https://www.researchgate.net/publication/318995288\_Troodontids\_Theropoda\_from\_the\_Dinosaur\_Park\_Formation\_Alberta\_with\_a\_description\_of\_a\_unique\_new\_taxon\_implications\_for\_deinonychosaur\_diversity\_in\_North\_America
* https://en.wikipedia.org/wiki/Latenivenatrix
Kryptops

Credit: Paleocolour on the Wikimedia Commons.

*Kryptops* is a potentially chimeric genus of abelisaurid theropod dinosaur that lived in Niger during the Early Cretaceous.

## Description

Paul Sereno and Stephen Brusatte (2008) named *Kryptops*, meaning "covered face" after evidence of tight integument. "Palaios" means "old". MNN GAD1, a maxilla, vertebrae, ribs and an articulated pelvic girdle and sacrum belonging to an adult 6–7 meters (19.7–23.0 feet) long, is the holotype. They place it as one of the earliest, basalmost abelisaurs. A notable heavily-textured surface of the maxilla with pits and blood vessel impressions suggest a sheath possibly made of keratin.

## Classification

It's placement as the basalmost Abelisauridae is prompted by a maxilla textured externally by vascular grooves and a narrow antorbital fossa. Matthew Carrano et al. (2012) find that it's postcrania (especially a pelvis and sacrum), which were found about 15 meters from the holotypic maxilla, actually belong to a carcharodontosaurid. Here, they suggest this carcharodontosaurid may possibly to *Eocarcharia*.

## References

1. ↑ 1.0 1.1 https://www.semanticscholar.org/paper/Basal-Abelisaurid-and-Carcharodontosaurid-Theropods-Sereno-Brusatte/f56350e33df3cf5bde537015186bcbf713261ac9
2. ↑ https://www.researchgate.net/figure/Abelisaurid-theropod-Kryptops-palaios-gen-et-sp-nov-MNN-GAD1-1-from-the-Lower\_fig1\_272152049
3. ↑ https://www.researchgate.net/publication/230808558\_The\_phylogeny\_of\_Tetanurae\_Dinosauria\_Theropoda
Lindwurmia

Credit: Nobu Tamura.

*Lindwurmia* is an extinct genus of rhomaleosaurid that lived in Germany during the Early Jurassic.

## Description

*Lindwurmia* is a moderately-sized plesiosaur, between 2 and 3 meters in length. *Lindwurmia* has a short, but robust premaxillary rostrum, which is constricted at the premaxilla-maxilla suture like the rest of Rhomaleosauridae. *Lindwurmia* is differentiated from other plesiosaurs based on minor differences. *Lindwurmia* is known from a single, uncatalogued specimen consisting of the anterior segment of its jaws, 69 vertebrae, incomplete pelvic and pectoral girdles and partial fore and hind limbs.

## Classification

*Lindwurmia* represents the basalmost spot in Rhomaleosauridae, and Plesiosauria in general.

## References

* https://pubmed.ncbi.nlm.nih.gov/30689058/
* http://spinops.blogspot.com/2019/05/lindwurmia-thiuda.html
Komlosaurus

Museum exhibit

*Komlosaurus* is an extinct ichnogenus of theropod dinosaur that lived in Hungary during the Early Jurassic.

## Description

*Komlosaurus* is known from several fossil trackway strips found in strip mines in Hungary. The trackways were first thought to have been created by an ornithomimid, but reevaluated to have been made by a theropod.

## References

https://en.wikipedia.org/wiki/Komlosaurus
Magallanodon

Credit: Mauricio Alvarez.

*Magallanodon* is an extinct genus of gondwanathere that lived in Chile during the Late Cretaceous.

## Description

*Magallanodon* is a relatively large mammal, only known from several molars found in Chile.

## Paleoecology

*Magallanodon* lived in the Dorotea Formation, and may have been herbivorous based off of *Magallanodon*'s flat molars.

## Notable Specimens

* CPAP 5916: The lower left molariform comprises the *Magallanodon* genus.

## References

* http://novataxa.blogspot.com/2020/06/magallanodon.html
* https://en.wikipedia.org/wiki/Magallanodon
Maccullochella

This page is about a genus that contains extinct and extant species; species marked with † are extinct.

## Statistics

### Synonyms

*Oligorus* (preoccupied)*Homodemus* (preoccupied)

### Diet

Carnivorous

*Maccullochella* is a genus of temperate perches (vernacularly referred to as cod) that live in Australia since the Miocene.

## Description

*Maccullochella* are known from the Murray-Darling rivers (Murray cod and trout cod), Clarence and Richmond Rivers (eastern freshwater cod), Brisbane River (*M. n. sp.*) and the Mary River (Mary River cod). They live long lives, with delayed sexual maturity and fertility. The are very vulnerable to overfishing, siltation and various, river regulation (via dams and weirs) other habitat degradation. Since European settlement, *Maccullochella* has not fared well. All are critically endangered, minus the Murray River cod, which is least concern.

## Species

* *M. ikei* (eastern freshwater cod)
* *M. macquariensis* (trout cod)
* *M. mariensis* (Mary River cod)
* *M. peeliii* (Murray cod)
* †*M. n. sp.* (Brisbane River cod)

## References

* https://en.wikipedia.org/wiki/Maccullochella
* https://www.iucnredlist.org/species/12576/103325360
Lance Albanerpetontid

The Lance Albanerpetontid is an unnamed genus of Amphibian from the Late Cretaceous of Wyoming.

## Description

The type specimen, UCMP 49547, is known from a left dentary. Estes (1981) described this taxon as a species of *Albanerpeton, A. nexuosus, however,* Daza et. al. (2020) *found Albanerpeton* to be paraphyletic and suggested that all Mesozoic taxa should be moved to their own genera. Fossilworks also states that this taxa is known from Alberta, Spain, Colorado, Montana, New Mexico, Texas, Utah. All localities seem reasonable besides the Spanish locality, and may just be Albanerpetontidae indet.

## Taxonomy

this phylogeny was recovered by Daza et al (2020):

## References

* http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon\_no=67753
* https://en.wikipedia.org/wiki/Albanerpeton