Eobaphetes

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Eobaphetes
Temporal range: Late Pennsylvanian, Westphalian D to Stephanian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Sarcopterygii
Clade: Tetrapodomorpha
Order: Embolomeri
Genus: Eobaphetes
Moodie, 1916
Type species
Erpetosuchus kansensis
Moodie, 1911

Eobaphetes is an extinct genus of embolomere which likely lived in the Pennsylvanian (late Carboniferous) of Kansas. The genus is based on several skull and jaw fragments of a single individual. They were originally described under the species Erpetosuchus kansasensis, but this was later changed to Eobaphetes kansasensis when it was determined that Erpetosuchus was preoccupied by a Triassic reptile.[1]

The provenance of Eobaphetes is uncertain. According to a now lost label, its specimens were supposedly found in a coal seam in Washington County, Kansas by fossil collector Gustav Hambach. However, coal deposits are unknown in this county. Plant fossils from Washington County, Kansas are of Early Permian age, which may suggest that Eobaphetes came from an unrecorded Early Permian coal seam. In 1963, A.S. Romer suggested that Hambach actually collected the specimens from Washington County, Arkansas.[2] Early Pennsylvanian coal deposits (the Namurian or Westphalian A Baldwin coal of the Bloyd Formation) have been found in that county. As a result, Eobaphetes may be one of the oldest embolomeres (if from Arkansas) or one of the youngest (if from Kansas). Hambach worked in both Kansas and Arkansas during his career.[1]

Chemical and spore analysis of the specimens' coal matrix finds little similarity to the Baldwin coal. Instead, it appears to be far more similar to the Nodaway coal of the Howard Limestone Formation. Spores indicate that this formation was deposited later in the Pennsylvanian, Westphalian D or Stephanian. The Howard Limestone is found in Missouri, Iowa, and Kansas. This suggests that Eobaphetes did come from Kansas, though not necessarily Washington County.[1]

Eobaphetes has often been compared to Anthracosaurus, and at one point was even synonymized with it. However, most authors consider it an eogyrinid like the majority of embolomeres. More specifically, it has been classified as a member of Leptophractinae, a subfamily of North American eogyrinids characterized by their circular orbits. Other leptophractines include Neopteroplax and Leptophractus.[1][3][4] Phylogenetic analyses suggest its closest relatives are Carbonoherpeton, "Pholiderpeton" (Eogyrinus) attheyi, and Calligenethlon.[5][6]

References[edit]

  1. ^ a b c d Panchen, A.L. (1977). "On Anthracosaurus russelli Huxley (Amphibia: Labyrinthodontia) and the family Anthracosauridae". Philosophical Transactions of the Royal Society B. 279 (968): 447–512. Bibcode:1977RSPTB.279..447P. doi:10.1098/rstb.1977.0096. JSTOR 2417840.
  2. ^ Romer, Alfred S. (February 1963). "The larger embolomerous amphibians of the American Carboniferous". Bulletin of the Museum of Comparative Zoology. 128: 415–454.
  3. ^ Clack, J.A. (1987). "Pholiderpeton scutigerum Huxley, an amphibian from the Yorkshire coal measures". Philosophical Transactions of the Royal Society of London B: Biological Sciences. 318 (1188): 1–107. Bibcode:1987RSPTB.318....1C. doi:10.1098/rstb.1987.0082.
  4. ^ Witzmann, Florian; Werneburg, Ralf; Milner, Andrew R. (2017-09-01). "A partial skull roof of an embolomere from Linton, Ohio (Middle Pennsylvanian) and its phylogenetic affinities". PalZ. 91 (3): 399–408. doi:10.1007/s12542-017-0374-4. ISSN 1867-6812. S2CID 89868170.
  5. ^ Klembara, Jozef; Hain, Miroslav; Ruta, Marcello; Berman, David S.; Pierce, Stephanie E.; Henrici, Amy C. (2020). "Inner ear morphology of diadectomorphs and seymouriamorphs (Tetrapoda) uncovered by high-resolution x-ray microcomputed tomography, and the origin of the amniote crown group". Palaeontology. 63 (1): 131–154. doi:10.1111/pala.12448. ISSN 1475-4983. S2CID 210778158.
  6. ^ Ruta, Marcello; Clack, Jennifer A.; Smithson, Timothy R. (2020). "A review of the stem amniote Eldeceeon rolfei from the Viséan of East Kirkton, Scotland". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 111 (3): 173–192. doi:10.1017/S1755691020000079. ISSN 1755-6910. S2CID 225452744.