Tanytrachelos ahynis

September 6, 2021, 2:16 pm

Tanytrachelos ahynis Olsen, 1979

Systematics: Archosauromorpha Tanystropheidae

Size: 20 cm long

Type Horizon and Locality: Late Triassic, Upper Member, Cow Branch Formation (Norian) Rockingham County, North Carolina, US

Type Specimen: YPM 7496, an articulated skeleton

This small lizard-like creature from the Late Triassic of North America, was an archosauromorph related to the large long-necked European Tanystropheus. It is known from abundant fossils of articulated specimens and was probably responsible of the many trackways (the trace fossils known as Gwyneddichnium majore) of a quadrupedal animal that scurried near the Late Triassic lakes of North America.

September 6, 2021

References:

Olsen, P. E. (1979). A new aquatic eosuchian from the Newark supergroup (Late Triassic-Early Jurassic) of North Carolina and Virginia. Postilla. 176. pp 1-14.

Lucas, S. G., Szajna, M. J., Lockley, M. G., Fillmore, D. L., Simpson, E. L., Klein, H. E. N. D. R. I. K., ... & Hartline, B. W. (2014). The middle-late Triassic tetrapod footprint ichnogenus Gwyneddichnium. New Mexico Museum of Natural History and Science Bulletin, 62, 135-156.

All illustrations on this site are copyrighted to Nobu Tamura. The low resolution versions of the images are licensed under Creative Commons Attribution- ShareAlike (CC BY-SA) license meaning that you are free to use them as long as you properly credit the author (© N. Tamura). High resolution versions are available upon request. Questions: contact me at nobu dot tamura at yahoo dot com.

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Symmoriiformes

September 12, 2021, 7:12 pm

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Symmoriiformes

Systematics: Chondrichthyes Holocephali Symmoriiformes

The Symmoriiformes form a group of cartilaginous fish related to the modern rat fishes. They had strange dorsal appendices that were probably used for sexual display. Symmorium is possibly a female Stethacanthus. They appeared during the Late Devonian and went extinct in the early Permian. Represented here:

Akmonistion zangerli Coates & Sequeira, 2001 (Manse Burn Formation, Serpukhovian, Scotland, UK)

Falcatus falcatus Lund, 1985 (Bear Gulch Limestone, Heath Formation, Serpukhovian, Montana, US)

Stethacanthus altonensis St. John & Worthen, 1875 (Bear Gulch Limestone, Heath Formation, Serpukhovian, Montana, US)

Symmorium reniforme Cope, 1893 (Linton Formation, Moscovian, Illinois, US)

September 12, 2021

References:

Maisey, J. G. (2009). The spine-brush complex in symmoriiform sharks (Chondrichthyes; Symmoriiformes), with comments on dorsal fin modularity. Journal of Vertebrate Paleontology, 29(1), 14-24.

Coates, M. I., & Sequeira, S. E. K. (2001). A new stethacanthid chondrichthyan from the Lower Carboniferous of Bearsden, Scotland. Journal of Vertebrate Paleontology, 21(3), 438-459.

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Colosteidae

September 18, 2021, 5:41 pm

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Colosteidae

Systematics: Tetrapodomorpha Stegocephalia

The Colosteidae were early tetrapods with unclear affinities. They had flat skulls, eel-like body with tiny limbs and were aquatic predators living in rivers and swamps of the Carboniferous period. Their body were covered with tiny scutes. Four species are currently recognized:

Colosteus scutellatus (Newberry, 1856) (Upper Freeport Coal Member, Westphalian D, Linton, Jefferson County, Ohio, US)

Deltaherpeton hiemstrae Bolt & Lombard, 2010 (Waugh Member, St. Louis Formation, Visean, Keokuk County, Iowa, US) [not represented]

Greererpeton burkemorani Romer, 1969 (Bickett Shale Member, Bluefield Formation, Serpukhovian, Monongalia County, West Virginia, US)

Pholidogaster pisciformis Huxley, 1862 (Lower Limestone Formation, Visean, Gilmerton, Scotland, UK)

In addition,

Ichthyerpeton bradleyae Wright & Huxley, 1866 from the Jarrow Colliery of Ireland, is considered a nomen dubium.

September 18, 2021

References:

Bolt, J. R., & Lombard, R. E. (2010). Deltaherpeton hiemstrae, a new colosteid tetrapod from the Mississippian of Iowa. Journal of Paleontology, 84(6), 1135-1151.

Godfrey, S. J. (1989). The postcranial skeletal anatomy of the Carboniferous tetrapod Greererpeton burkemorani Romer, 1969. Philosophical Transactions of the Royal Society of London. B, Biological Sciences, 323(1213), 75-133.

Hook, R. W. (1983). Colosteus scutellatus (Newberry): a primitive temnospondyl amphibian from the Middle Pennsylvanian of Linton, Ohio. American Museum novitates; no. 2770.

Panchen, A. L. (1975). A new genus and species of anthracosaur amphibian from the Lower Carboniferous of Scotland and the status of Pholidogaster pisciformis Huxley. Philosophical Transactions of the Royal Society of London. B, Biological Sciences, 269(900), 581-637.

Smithson, T. R. (1982). The cranial morphology of Greererpeton burkemorani Romer (Amphibia: Temnospondyli). Zoological Journal of the Linnean Society, 76(1), 29-90.

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Diplocaulidae

September 19, 2021, 7:58 pm

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Diplocaulidae

Systematics: Lepospondyli Nectridea Diplocaulidae

These lepospondyl tetrapods have horn-like protrusions on their skull. The boomerang shape headed Diplocaulus is their most famous representative. Apparently, the protrusions help them swim, providing a significant lift when swimming upward. They lived from the Early Pennsylvanian to the early Permian. Represented here:

Batrachiderpeton lineatum Hancock and Atthey 1869 (Early Pennsylvanian of England, UK)

Diceratosaurus brevirostris (Cope, 1874) (Middle Pennsylvanian of Ohio, US)
Diplocaulus magnicornis Cope, 1882 (Early Permian of Texas, US)

Diploceraspis burkei Romer, 1952 (Early Permian, West Virginia, US)
Keraterpeton galvani Huxley, 1867 (Early Pennsylvanian of England, UK)

September 19, 2021

References:

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Amphibamiformes

September 26, 2021, 3:35 pm

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Amphibamiformes

Systematics: Temnospondyli Dissorophoidea Amphibamiformes

Amphibamiformes is a clade within the Dissorophoid temnospondyls created by Schoch in 2018. It includes the Micropholidae, the Amphibamidae and the Branchiosauridae. It is believed modern Lissamphibians (frogs, toads, salamanders and newts) evolved from within this group.

Represented here:

Platyrhinops lyelli Wyman, 1858 (Middle Pennsylvanian, Ohio, US)

Micropholidae:

Micropholis stowi Huxley, 1859 (Early Triassic, Katberg Formation, South Africa)

Amphibamidae:

Amphibamus grandiceps Cope, 1865 (Middle Pennsylvanian, Illinois, US)

Doleserpeton annectens Bolt, 1969 (Early Permian, Garber Formation, Oklahoma, US)

Branchiosauridae:

Apateon pedestris von Meyer 1840 (Late Pennsylvanian, Meisenheim Formation, germany)

Branchiosaurus salamandroides Fritsch, 1875 (Middle Pennsylvanian, Kladno Formation, Czech Republic)

Leptorophus tener (Schonfeld, 1911) (Early Permian, Bortewitz Formation, Germany)

Stem Lissamphibian:

Gerobatrachus hottoni Anderson et al., 2008 (Early Permian, Clear Fork Group, Texas, US)

September 26, 2021

References:

Schoch, R. R. (2019). The putative lissamphibian stem-group: phylogeny and evolution of the dissorophoid temnospondyls. Journal of Paleontology, 93(1), 137-156.

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Diadectomorpha

October 3, 2021, 9:57 pm

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Diadectomorpha

Systematics: Reptiliomorpha Diadectomorpha

Diadectomorph form a clade of medium to large size animals that had a mixture of amphibian and reptilian characteristics. They lived during the Late Pennsylvanian to the Early Permian period and included both predators and herbivores

Represented here:

Limnoscelis paludis Williston, 1911 (Late Pennsylvanian, New Mexico, US)

Tseajaia campi Vaughn, 1964 (Early Permian, Utah, US)

Diadectes sideropelicus Cope, 1878 (Early Permian, Texas, US)

Diasparactus zenos Case, 1910 (Late Pennsylvanian, New Mexico, US)

Orobates pabsti Berman et al., 2004 (Early Permian, Germany)

Silvadectes absitus (Berman et al., 1998) (Early Permian, Germany)

October 3 2021

References:

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Cervifurca nasuta

October 17, 2021, 6:12 pm

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Cervifurca nasuta Zangerl, 1997

Systematics: Chondrichthyes Holocephali Iniopterygiformes Iniopterygidae

Size: 25 cm long

Type Horizon and Locality: Late Carboniferous, Excello Shale, Carbondale Formation (Westphalian D), Pike County, Indiana, US.

Type Specimen FMNH PF13228, partial skeleton lacking the anterior end of the skull

Iniopterygiformes is an extinct order of small cartilaginous fish related to modern ratfish. They are characterized by enormous pectoral fins placed almost on their back rather than on their sides. Cervifurca ("deer fork") is one of the oddest members, being dorso-ventrally flattened. It probably lived at the bottom of the seas.

October 17, 2021

References:

Zangerl, R. (1997). Cervifurca nasuta n. gen. et sp., an interesting member of the Iniopterygidae (Subterbranchialia, Chondrichthyes) from the Pennsylvanian of Indiana, USA (No. 35). Field Museum of Natural History.

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Allenypterus montanus

November 21, 2021, 6:01 pm

≫ Next: Rainerichthys zangerli

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Allenypterus montanus Melton, 1969

Systematics: Sarcopterygii Actinistia Hadronectoridae

Size: 12 cm long

Type Horizon and Locality: Early Carboniferous, Bear Gulch Limestone member, Heath Formation, Big Snowy Group (Namurian) Fergus County, Montana, US.

Type Specimen MV 2555, complete skeleton

This odd looking fish was originally described as a ray-finned fish (Actinopterygia) but it was later realized that it was an unusually-shaped coelacanth instead.

November 21, 2021

References:

Lund, R., & Lund, W. (1984). New genera and species of coelacanths from the Bear Gulch Limestone (Lower Carboniferous) of Montana (USA). Geobios, 17(2), 237-244.

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Rainerichthys zangerli

November 26, 2021, 7:58 pm

≫ Next: Titanichthys clarki

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Rainerichthys zangerli Grogan & Lund, 2009

Systematics: Chondrichthyes Holocephali Iniopterygiformes Iniopterygidae

Size: 15 cm long

Type Horizon and Locality: Early Carboniferous, Bear Gulch Limestone member, Heath Formation, Big Snowy Group (Namurian) Fergus County, Montana, US.

Type Specimen CM 46097, almost complete specimen

Iniopterygiformes is an extinct order of small cartilaginous fish related to modern ratfish. They are characterized by enormous pectoral fins placed almost on their back rather than on their sides. Rainerichthys zangerli ("Rainer Zangerl's fish") had a laterally compressed body and some unique tooth whorls at the front of its mouth.

November 26, 2021

References:

Grogan, E. D., & Lund, R. (2009). Two new iniopterygians (Chondrichthyes) from the Mississippian (Serpukhovian) Bear Gulch Limestone of Montana with evidence of a new form of chondrichthyan neurocranium. Acta Zoologica, 90, 134-151.

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Titanichthys clarki

January 22, 2022, 5:01 pm

≫ Next: Monjurosuchus splendens

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Titanichthys clarki Newberry, 1887

Systematics: Placodermi Arthrodira Dinichthyloidea Titanichthyidae

Size: 6 m long

Type Horizon and Locality: Late Devonian, Cleveland Shale member, Ohio Shale Formation, Ohio, US

Type Specimen :

Titanichthys was a large placoderm fish from the Late Devonian. Its edentulous weak jaws indicate that it was most probably a suspension feeder similarly to the modern basking and whale sharks. Five species are known from North America to which T. clarki from the famous Cleveland Shale of Ohio, was the largest.

January 22, 2022

References:

Boyle, J., & Ryan, M. J. (2017). New information on Titanichthys (Placodermi, Arthrodira) from the Cleveland Shale (Upper Devonian) of Ohio, USA. Journal of Paleontology, 91(2), 318-336.

Coatham, S. J., Vinther, J., Rayfield, E. J., & Klug, C. (2020). Was the Devonian placoderm Titanichthys a suspension feeder?. Royal Society open science, 7(5), 200272.

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Monjurosuchus splendens

January 23, 2022, 6:39 pm

≫ Next: Eretmorhipis carrolldongi

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Monjurosuchus splendens Endo, 1940

Systematics: Sauria Choristodera

Size: 40 cmlong

Type Horizon and Locality: Early Cretaceous, Yixian Formation, Jehol Group (Aptian) Liaoning Province, China

Type Specimen : The holotype specimen has been destroyed during WWII, the designed neotype is GMV 2167, a nearly complete skeleton with soft tissue preserved

Choristoderes form a small group of lizard-like semi-aquatic creatures that appeared during the middle Jurassic and went extinct in the Late Miocene. Monjurosuchus ("Manchukuo's crocodile") is known for several specimens both from the Liaoning province of China and Japan. It was a small member of the group, measuring less than half-a-meter in length. Some fossils show soft tissue impressions indicating that the feet were webbed and the body covered with small scales, with two rows of larger scutes along the back.

January 23, 2022

References:

Matsumoto, R., Evans, S. E., & Manabe, M. (2007). The choristoderan reptile Monjurosuchus from the Early Cretaceous of Japan. Acta Palaeontologica Polonica, 52(2).

Gao, K. Q., & Li, Q. (2007). Osteology of Monjurosuchus splendens (Diapsida: Choristodera) based on a new specimen from the Lower Cretaceous of western Liaoning, China. Cretaceous Research, 28(2), 261-271.

Keqin, G., Evans, S., Qiang, J., Norell, M., & Shu'An, J. (2000). Exceptional fossil material of a semi-aquatic reptile from China: the resolution of an enigma. Journal of Vertebrate Paleontology, 20(3), 417-421.

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Eretmorhipis carrolldongi

February 5, 2022, 6:06 pm

≫ Next: Paludidraco multidentatus

≪ Previous: Monjurosuchus splendens

Eretmorhipis carrolldongi Chen et al., 2015

Systematics: Sauria Ichthyosauromorpha Hupehsuchia Hupehsuchidae

Size: 80 cm long

Type Horizon and Locality: Early Triassic, Jialingjiang Formation, Hubei Province, China

Type Specimen : WGSC 26020, almost complete skeleton missing the skull

Eretmorhipis was an unusual aquatic creature with a tiny head of a platypus, tiny eyes, and large fan-shaped paddles as limbs.

February 5, 2022

References:

Cheng, L., Motani, R., Jiang, D. Y., Yan, C. B., Tintori, A., & Rieppel, O. (2019). Early Triassic marine reptile representing the oldest record of unusually small eyes in reptiles indicating non-visual prey detection. Scientific reports, 9(1), 1-11.

Chen, X. H., Motani, R., Cheng, L., Jiang, D. Y., & Rieppel, O. (2015). A new specimen of Carroll’s mystery hupehsuchian from the Lower Triassic of China. PloS one, 10(5), e0126024.

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Paludidraco multidentatus

February 6, 2022, 6:37 pm

≫ Next: Psephochelys polyosteoderma

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Paludidraco multidentatus de Miguel Chaves et al., 2018

Systematics: Sauria Sauropterygia Nothosauroidea Simosauridae

Size: 2.5 m long

Type Horizon and Locality: Late Triassic, Keuper (Carnian-Norian boundary) Guadalajara, Spain

Type Specimen : MUPA-ATZ0101, skull and partial postcranial skeleton

Paludidraco ("marsh dragon") was a rather odd nothosaur with a slender and fragile jaw equipped with many small teeth arranged in a comb-like structure. The ribs were very thick, similarly to modern sea cows, providing neutral buoyancy to the body. It was probably a filter-feeder.

February 6, 2022

References:

de Miguel Chaves, C., Ortega, F., & Pérez-García, A. (2018). New highly pachyostotic nothosauroid interpreted as a filter-feeding Triassic marine reptile. Biology letters, 14(8), 20180130.

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Psephochelys polyosteoderma

February 13, 2022, 8:53 pm

≫ Next: Protoichthyosaurus prostaxalis

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Psephochelys polyosteoderma Li and Rieppel, 2002

Systematics: Sauria Sauropterygia Placodontia Placochelyidae

Size: 2.5 m long

Type Horizon and Locality: Late Triassic, Lower Xiaowa Formation (Carnian), Guizhou Province, China

Type Specimen : IVPP V12442, a partial skeleton

Placodonts form a group of aquatic shell-eating sauropterygians that thived during the Middle and Late Triassic period. The most derived form looked a lot like turtles. Psephochelys ("pebble turtle") is one of the more recently discovered placodonts known from almost complete skeletons.

February 13, 2022

References:

Li, C., & Rieppel, O. (2002). A new cyamodontoid placodont from Triassic of Guizhou, China. Chinese Science Bulletin, 47(5), 403-407.

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Protoichthyosaurus prostaxalis

February 20, 2022, 8:28 pm

≫ Next: Ankitokazocaris chaohuensis

≪ Previous: Psephochelys polyosteoderma

Protoichthyosaurus prostaxalis Appleby, 1979

Systematics: Sauria Ichthyosauromorpha Ichthyopterygia Ichthyosauria Ichthyosauridae

Size: 3.5 m

Type Horizon and Locality: Early Triassic, Blue Lias Formation (Early Hettangian) England, UK

Type Specimen : BRLSI M3553 (old B. 1963'5/O.S.), partial skull, pectoral girdle and forefins.

The genus Protoichthyosaurus ("First Fish Lizard") was erected by Appelby in 1979 but due to its similarity with Ichthyosaurus, it was synonymized with the later. The name was resuscitated by Lomax et al. in 2017 in view of differences in the forefin morphology. There are currently two recognized species of Protoichthyosaurus, the type species, P. prostaxalis and the smaller P. applebyi, both from the Lower Lias of England.

February 20, 2022

References:

Lomax, D. R., Massare, J. A., & Mistry, R. T. (2017). The taxonomic utility of forefin morphology in Lower Jurassic ichthyosaurs: Protoichthyosaurus and Ichthyosaurus. Journal of Vertebrate Paleontology, 37(5), e1361433.

Lomax, D. R., & Massare, J. A. (2018). A second specimen of Protoichthyosaurus applebyi (Reptilia: Ichthyosauria) and additional information on the genus and species. Paludicola, 11, 164-178.

Lomax, D. R., Porro, L. B., & Larkin, N. R. (2019). Descriptive anatomy of the largest known specimen of Protoichthyosaurus prostaxalis (Reptilia: Ichthyosauria) including computed tomography and digital reconstruction of a three-dimensional skull. PeerJ, 7, e6112.

Lomax, D. R., Massare, J. A., & Evans, M. (2020). New information on the skull roof of Protoichthyosaurus (Reptilia: Ichthyosauria) and intraspecific variation in some dermal skull elements. Geological Magazine, 157(4), 640-650.

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Ankitokazocaris chaohuensis

February 27, 2022, 12:42 pm

≫ Next: Glyptolepis paucidens

≪ Previous: Protoichthyosaurus prostaxalis

Ankitokazocaris chaohuensis Ji et al., 2017

Systematics: Arthropoda ?Crustacea Thylacocephala

Size: 6 cm

Type Horizon and Locality: Early Triassic, Nanlinghu Formation (Olenekian) Anhui Province, China

Type Specimen : NIGP 163032, a carapace

The Thylacocephalans form a group of extinct Arthropods of uncertain affinities. They are characterized by a laterally compressed carapace that cover the entire body, with large compound eyes and three pairs of raptorial limbs. Their exact phylogenetic placement is unknown as some fundamental details about their anatomy are lacking, but most specialists placed them tentatively among the crustaceans.

February 27, 2022

References:

Ji, C., Tintori, A., Jiang, D., & Motani, R. (2017). New species of Thylacocephala (Arthropoda) from the Spathian (Lower Triassic) of Chaohu, Anhui Province of China. PalZ, 91(2), 171-184.

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Glyptolepis paucidens

March 13, 2022, 4:32 pm

≫ Next: Pterichthyodes milleri

≪ Previous: Ankitokazocaris chaohuensis

Glyptolepis paucidens (Agassiz, 1844)

Systematics: Sarcopterygii Porolepiformes Holoptychiidae

Size: 60 cm

Type Horizon and Locality: Middle Devonian, Achanarras Fish Bed, Lower Caithness Flagstone Group, Middle Old Red Sandstone (Eifelian), Caithness, Scotland, UK

Type Specimen : NHM P.545, lower jaw

With size reaching more than half a meter, the porolepiform Glyptolepis was the top predator of the Middle Devonian Achanarras fish community of a large freshwater lake that occupied today's NortheEast Scotland. Glyptolepis paucidens is the slimmer and larger of the two species that lived in that lake at that time (the other being G. leptopterus).

March 13, 2022

References:

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Pterichthyodes milleri

March 13, 2022, 8:54 pm

≫ Next: Albalimulus bottoni

≪ Previous: Glyptolepis paucidens

Pterichthyodes milleri (Miller, 1841)

Systematics: Placodermi Antiarchi Pterichthyoidae

Size: 25 cm

Type Horizon and Locality: Middle Devonian, Achanarras Fish Bed, Lower Caithness Flagstone Group, Middle Old Red Sandstone (Eifelian), Caithness, Scotland, UK

Type Specimen : NMS G.1859.33.5 (Lectotype), an almost complete articulated specimen

This odd-looking armored fish from the Middle Devonian of Scotland was probably a bottom feeder. It was originally named Pterichthys milleri but the generic name was preoccupied.

March 13, 2022

References:

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Albalimulus bottoni

March 26, 2022, 7:12 pm

≫ Next: Cloudina hartmannae

≪ Previous: Pterichthyodes milleri

Albalimulus bottoni Bicknell & Pates, 2019

Systematics: Arthropoda Chelicerata Xiphosurida Limulina Limuloidea

Size: 2.5 cm

Type Horizon and Locality: Early Carboniferous, Ballagan Formation (Tournaisian), Berwickshire, Scotland, UK

Type Specimen : BGS.GSE2028/9680 (part/counterpart).

Horseshoe crabs first appeared in the fossil record during the Late Ordovician period and have hardly changed since then. Albalimulus (the name combines the Gaelic name of Great Britain, Alba, with the genus name of the extant horseshoe crab, Limulus) was a small one from the Early Carboniferous of Scotland, possibly the earliest member of the modern Limulidae family. It is known from the part and counterpart of a single fossil missing the telson (terminal appendage of the carapace).

March 26, 2022

References:

Bicknell, R. D., & Pates, S. (2019). Xiphosurid from the Tournaisian (Carboniferous) of Scotland confirms deep origin of Limuloidea. Scientific reports, 9(1), 1-13.

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Cloudina hartmannae

April 3, 2022, 5:40 pm

≫ Next: Ernietta plateauensis

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Cloudina hartmannae Germs, 1972

Systematics: Animalia Cloudinidae

Size: 8-150 mm

Type Horizon and Locality: Late Ediacaran, Schwartzkalk Limestone Member, Kuibis Formation, Nama Group, Namibia

Type Specimen : S.A.M.K 1072

Cloudina were tiny organisms with a worldwide distribution that were among the first animals with mineralized skeletons to appear in the fossil record. The fossils consist of a series of stacked vase-like tubes. Recent tomographic analyses of specimens from the Wood Canyon Formation of Nevada, USA, indicate the presence of a a digestive tract within the tube, the earliest known evidence of a gut in the fossil record. The representation of the living organism here is hypothetical.

April 3, 2022

References:

Schiffbauer, J. D., Selly, T., Jacquet, S. M., Merz, R. A., Nelson, L. L., Strange, M. A., ... & Smith, E. F. (2020). Discovery of bilaterian-type through-guts in cloudinomorphs from the terminal Ediacaran Period. Nature communications, 11(1), 1-12.

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