Batropetes

Last updated

Batropetes
Temporal range: Early Permian
Batropetes.jpg
Restoration of Batropetes fritschi
Batropetes sp 54.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Order: Microsauria
Family: Brachystelechidae
Genus: Batropetes
Carroll and Gaskill, 1971
Species

B. appelensisGlienke, 2015
B. fritschiCarroll, 1991 (type)
B. niederkirchensisGlienke, 2013
B. palatinusGlienke, 2015

Contents

Synonyms
  • BrachystelechusCarroll and Gaskill, 1978
  • PetrobatesCredner, 1890

Batropetes is an extinct genus of brachystelechid recumbirostran "microsaur". Batropetes lived during the Sakmarian stage [a] of the Early Permian. Fossils attributable to the type species B. fritschi have been collected from the town of Freital in Saxony, Germany, near the city of Dresden. Additional material has been found from the Saar-Nahe Basin in southwestern Germany and has been assigned to three additional species: B. niederkirchensis, B. palatinus, and B. appelensis.

Description

Fossil Batropetes sp.JPG
Fossil

Batropetes is small and short-bodied for a microsaur. Its average total body length was about 8 centimetres (3.1 in). [1] The orbits are large and the skull is short. Batropetes possesses scales on its underside that are similar to those of reptiles. [2]

Batropetes is distinguished from Carrolla , another brachystelechid microsaur, by the presence of three cusps on the premaxillary and anterior dentary teeth. In Carrolla, there are only two cusps. Additional diagnostic features seen in Batropetes include a supraoccipital bone that is not fused to the otic capsule, the presence of a retroarticular process (a projection at the back of the lower jaw), and two proximal bones in the tarsus. [2]

Classification

The first known material now attributed to the genus Batropetes was originally referred to the genus Hyloplesion in 1882. [3] Several specimens from Freital were described under the name Hyloplesion Fritschi as small non-labyrinthodonts. Three years later, the specimens originally referred to as Hyloplesion Fritschi were reassigned by Carl Hermann Credner to the genus Hylonomus under the name Hylonomus fritschia. [b] [4] Newly discovered specimens of other forms from the same locality led Credner to believe that two taxa existed. He named one, an amphibian, Hylonomus geinitzi, and the other, a reptile, Petrobates truncatus. [5]

Later preparation of the material examined by Credner through a technique of removing the soft bone from the surrounding matrix mechanically and casting the cavities in liquid latex has revealed more anatomical detail suggesting that three taxa were present in Freital, not two. A specimen previously referred to Petrobates truncatus was first considered by Robert L. Carroll and Pamela Gaskill in 1978 to be a microsaur rather than a reptile. [6] It was considered distinct from Petrobates, then considered a captorhinomorph, based only on the structure of the atlas.

Of the three species represented in Frietal, Hylonomus geinitzi, as described by Credner, has since been reassigned to the microsaur genus Saxonerpeton , and Petrobates truncatus was designated as Batropetes truncatus by Carroll and Gaskill in 1971. [6] [7] Carroll and Gaskill still referred to B. truncatus as a captorhinomorph reptile.

Carroll and Gaskill described a new microsaur in 1978 from Frietal, which they called Brachystelechus fritschi. [6] It was noted that the skull of Brachystelechus bore a striking resemblance to that of Batropetes, which was considered to be unrelated. It differed from Batropetes in that it possessed an internarial bone which was not seen in known specimens of Batropetes.

A newly discovered specimen of microsaur from the Saar-Nahe district in southwestern Germany has confirmed that Brachystelechus and Batropetes represent the same species. [2] The characters that previously distinguished the two genera from one another are all found in one specimen, known as SMNS 55884, housed in the Staatliches Museum für Naturkunde Stuttgart. This a complete specimen preserved in ventral view and consisting of a part and counterpart. The skull roof was examined by excavating the matrix from the top of the block and exposing more anatomical features. The occipital condyle in SMNS 55884, not noticeable in the specimen of Brachystelechus, clearly indicates that it is a microsaur rather than a captorhinomorph reptile. An interfrontal bone is seen in material once referred to Brachystelechus but not in any material known from specimens previously attributed to Batropetes. This may be a result of poor preservation, or perhaps intraspecific variation. The parietals of the specimen are wide and the skull is short, both of which are features that associate it with the North American genera Carrolla and Quasicaecilia . [8] [9] On the basis of these and other similarities, Carroll, who described the new material in 1991, constructed a new microbrachomorph family called the Brachystelechidae to include Batropetes, Carrolla, and Quasicaecilia. [2]

A 2013 study of Batropetes erected a new species, Batropetes niederkirchensis, for specimen SMNS 55884. SMNS 55884 was noted to differ from the type specimen of B. fritschi in the number of presacral vertebrae, the width between the eye sockets, the shape of the prefrontal, postorbital, and scapulocoracoid bones, and the position of the obturator foramen in the hips. [10] Two additional species, B. appelensis and B. palatinus, were named in 2015 on the basis of new material found from the Saar-Nahe Basin. [1]

During the 2010s, recumbirostran microsaurs, including brachystelechids, were increasingly considered to be early diverging sauropsids, rather than reptiliomorphs. [11]

Notes

  1. ^ In European lithostratigraphy this is known as the Rotliegend.
  2. ^ Hylonomus is now known to be a genus of early reptile within the family Protorothyrididae.

Related Research Articles

<span class="mw-page-title-main">Araeoscelidia</span> Extinct clade of reptiles

Araeoscelidia or Araeoscelida is a clade of extinct amniotes superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the genera Araeoscelis, Petrolacosaurus, the possibly aquatic Spinoaequalis, and less well-known genera such as Kadaliosaurus and Zarcasaurus. This clade is usually considered to be the sister group to all later diapsids.

<i>Palaeohatteria</i> Extinct genus of synapsids

Palaeohatteria is an extinct genus of basal sphenacodonts known from the Early Permian period of Saxony, Germany. It contains a single species, Palaeohatteria longicaudata.

<i>Asaphestera</i> Extinct genus of tetrapods

Asaphestera is an extinct genus of a synapsid described on the basis of fossils from the Carboniferous of the Joggins locality in Nova Scotia, Canada. It was originally described as an undetermined lepospondyl and subsequently classified as a microsaur within the family Tuditanidae. A study published in May 2020 found that specimens referred to Asaphestera represented several unrelated species. Steen (1934)'s original species name Asaphestera platyris was retained for a skull which has been re-evaluated as the earliest known synapsid.

<i>Boii</i> (genus) Extinct genus of amphibians

Boii is an extinct genus of microsaur within the family Tuditanidae. It was found in Carboniferous coal from mines near the community of Kounov in the Czech Republic. The only remains of the genus consist of a crushed skull, shoulder girdle bones, and scales, which were similar to microsaurian elements originally referred to Asaphestera. Boii can be characterized by its heavily sculptured skull, thin ventral plate of the clavicles, and a larger number of fangs on the roof of the mouth. For many years the type and only known species, Boii crassidens, was considered to be a species of Sparodus, until 1966 when Robert Carroll assigned it to its own genus.

<i>Carrolla</i> Extinct genus of amphibians

Carrolla is an extinct genus of brachystelechid 'microsaur' that lived in the Lower Permian in North America. It was named in 1986 by American paleontologists Wann Langston and Everett Olson. The type species, Carrolla craddocki, is the only known species.

<i>Euryodus</i> Extinct genus of amphibians

Euryodus is an extinct genus of microsaur within the family Gymnarthridae. Euryodus is a Lepospondyl from the clade Microsauria that lived during the Lower Permian. The name comes from Greek, meaning ‘broad-tooth’. It has been found in the southern half of North America, from its original discovery in Texas up to Utah.

Hapsidopareion is an extinct genus of microsaur belonging to the family Hapsidopareiidae. Fossils have been found in the early Permian of Oklahoma.

Llistrofus is an extinct genus of early Permian microsaur within the family Hapsidopareiidae that is known from Oklahoma.

<i>Odonterpeton</i> Extinct genus of tetrapods

Odonterpeton is an extinct genus of "microsaur" from the Late Carboniferous of Ohio, containing the lone species Odonterpeton triangulare. It is known from a single partial skeleton preserving the skull, forelimbs, and the front part of the torso. The specimen was found in the abandoned Diamond Coal Mine of Linton, Ohio, a fossiliferous coal deposit dated to the late Moscovian stage, about 310 million years ago.

<i>Quasicaecilia</i> Extinct genus of tetrapods

Quasicaecilia is an extinct genus of microsaur. It is known from the Early Permian of Texas in the United States. A single specimen is known, collected from the Texas Permian redbeds by Charles Hazelius Sternberg in 1917. It was originally identified as a specimen of the gymnarthrid microsaur Cardiocephalus. The skull is small, less than 2 centimetres (0.79 in) in length, and the otic capsule is very large in comparison to the rest of the skull. The skull of Quasicaecilia superficially resembles those of extant but unrelated caecilians, hence the genus name. Quasicaecilia was assigned to the new family Brachystelechidae in 1991 along with the genera Batropetes and Carrolla.

Pariotichus is an extinct genus of gymnarthrid microsaurs from the early Permian of Texas.

<i>Hyloplesion</i> Extinct genus of tetrapods


Hyloplesion is an extinct genus of microbrachomorph microsaur. It is the type and only genus within the family Hyloplesiontidae. Fossils have been found from the Czech Republic near the towns of Plzeň, Nýřany, and Třemošná, and date back to the Middle Pennsylvanian. The type species is H. longicostatum, named in 1883. Two species belonging to different genera, Seeleya pusilla and Orthocosta microscopica, have been synonymized with H. longicostatum and are thought to represent very immature individuals.

<span class="mw-page-title-main">Brachystelechidae</span> Extinct family of tetrapods

Brachystelechidae is an extinct family of Early Permian microsaurs. The family was first named by Robert L. Carroll and Pamela Gaskill in 1978, with the only member being Brachystelechus fritschi. Brachystelechus fritschi has since been reassigned to the genus Batropetes. Genera assigned to the family include: Batropetes, from Germany; Carrolla, from Texas; Quasicaecilia, also from Texas; Diabloroter, from the Mazon Creek lagerstätte of Illinois; and Bromerpeton from the Tambach Formation of Germany.

<span class="mw-page-title-main">Ostodolepidae</span> Extinct family of tetrapods

Ostodolepidae, also spelled Ostodolepididae, is an extinct family of Early Permian tetrapods. Initially they were considered microsaurs, but later were assigned to the group Recumbirostra. Ostodolepids were relatively large, reaching lengths of up to 2 feet (61 cm), terrestrial, and presumably fossorial. Ostodolepid remains have been found from Early Permian beds in Texas, Oklahoma, and Germany.

<span class="mw-page-title-main">Recumbirostra</span> Extinct clade of tetrapods

Recumbirostra is a clade of tetrapods which lived during the Carboniferous and Permian periods. They are thought to have had a fossorial (burrowing) lifestyle and the group includes both short-bodied and long-bodied snake-like forms. At least one species, the long-bodied molgophid Nagini mazonense, lost its forelimbs entirely. Recumbirostra includes the families Pantylidae, Gymnarthridae, Ostodolepidae, Rhynchonkidae and Brachystelechidae, with additional families such as Microbrachidae and Molgophidae being included by some authors. Brachystelechidae and Molgophidae have also been grouped together in the suggested clade Chthonosauria.

<i>Acanthostomatops</i> Extinct genus of amphibians

Acanthostomatops is an extinct genus of zatracheidid temnospondyl from the Lower Permian Döhlen Basin of Saxony.

Huskerpeton is an extinct genus of recumbirostran from the Early Permian period. They belong to the order Microsauria, which was established in 1863 by Dawson, and was quickly expanded to include many different small taxa. They lived in what is now Nebraska and Kansas. The holotype of Huskerpeton was uncovered at the Eskridge formation in Nebraska, which is part of how it got its name.

Proxilodon is an extinct genus of recumbirostran microsaur from the Early Permian Speiser Formation of Kansas, United States. It contains a single species, Proxilodon bonneri,.

<span class="mw-page-title-main">Palaeohatteriidae</span> Extinct family of Permian organisms

Palaeohatteriidae is an extinct family of basal sphenacodonts known from the Early Permian period of Saxony, Germany. Two genera are known: Palaeohatteria and Pantelosaurus.

References

  1. 1 2 Glienke, S. (2015). "Two new species of the genus Batropetes(Tetrapoda, Lepospondyli) from the Central European Rotliegend (basal Permian) in Germany". Journal of Vertebrate Paleontology. 35 (2): e918041. Bibcode:2015JVPal..35E8041G. doi:10.1080/02724634.2014.918041. S2CID   83855041.
  2. 1 2 3 4 Carroll, R. L. (1991). "Batropetes from the Lower Permian of Europe- a microsaur, not a reptile". Journal of Vertebrate Paleontology. 11 (2): 229–242. Bibcode:1991JVPal..11..229C. doi:10.1080/02724634.1991.10011390.
  3. Geinitz, H. B.; Deichmüller, J. V. (1882). "Die fossilen Saurier in dem Kalke des Rothliegenden von Niederhässlich im Plauenschen Grunde bei Dresden". Mineral.-Geol. Praehist. Mus. Dresden: 1–3.
  4. Credner, H. (1885). "Die Stegocephalen aus dem Rothliegenden des Plauen'schen Grundes bei Dresden. V. Theil". Zeitschrift der Deutschen Geologischen Gesellschaft. 37: 694–736.
  5. Credner, H. (1890). "Die Stegocephalen und Saurier aus dem Rothliegenden des Plauen'schen Grundes bei Dresden. IX. Theil. Hylonomus geinitzi Cred. Petrobates truncatus Cred. Discosaurus permianus Cred". Zeitschrift der Deutschen Geologischen Gesellschaft. 42: 240–277.
  6. 1 2 3 Carroll, R. L.; Gaskill, P. (1978). The Order Microsauria. Memoirs of the American Philosophical Society. Vol. 126. DIANE Publishing. pp. 1–211. ISBN   9780871691262.
  7. Carroll, R. L.; Gaskill, P. (1971). "A captorhinomorph reptile from the Lower Permian of Europe". Journal of Paleontology. 45 (3): 450–463.
  8. Langston, W. Jr.; Olson, E. C. (1986). "Carrolla craddocki, a new genus and species of microsaur from the Lower Permian of Texas". Pearce-Sellards Series, Texas Memorial Museum. 43: 1–20.
  9. Carroll, R. L. (1990). "A tiny microsaur: size constraints in Palaeozoic tetrapods". Palaeontology. 33: 1–17.
  10. Glienke, S. (2013). "A taxonomic revision of Batropetes (Amphibia, Microsauria) from the Rotliegend (basal Permian) of Germany". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 269 (1): 73–96. doi:10.1127/0077-7749/2013/0336.
  11. Mann, Arjan; Pardo, Jason D; Sues, Hans-Dieter (2022-07-19). "Osteology and phylogenetic position of the diminutive 'microsaur' Odonterpeton triangulare from the Pennsylvanian of Linton, Ohio, and major features of recumbirostran phylogeny". Zoological Journal of the Linnean Society. 197 (3): 641–655. doi: 10.1093/zoolinnean/zlac043 . ISSN   0024-4082.