The first record of the chimaeroid genus Edaphodon (Chondrichthyes, Holocephali) from Antarctica (Snow Hill Island Formation, Late Cretaceous, James Ross Island)

GOUIRIC CAVALLI, SOLEDAD; CABRERA, DANIEL ALFREDO; ALBERTO LUIS CIONE; O'GORMAN, JOSÉ; CORIA, RODOLFO; FERNÁNDEZ, MARTA

JOURNAL OF VERTEBRATE PALEONTOLOGY

SOC VERTEBRATE PALEONTOLOGY

Lugar: Lawrence; Año: 2015

0272-4634

A new species of an edaphodontid holocephalian, Edaphodon snowhillensis sp. nov., is described based on a complete dentition collected in the late Campanian Herbert Sound Member of the Snow Hill Island Formation James Ross Island, Antarctica. The specimen consists of two almost complete vomerine, mandibular and palatine tooth plates. The new species is characterized by a unique character combination from which the presence of a subquadrangular vomerine tooth plates and a horse hoof-shaped anterior outer tritor in the mandibular tooth plates appear to be unique characters among the edaphodontids. E. snowhillensis sp. nov. represents the most complete dentition of a holocephalian fish from the Southern Hemisphere and the earliest record of the genus Edaphodon from the Antarctic continent and the Weddellian Biogeographic Province. Also, E. snowhillensis sp. nov. is the southernmost specimen of this genus and according to the size of the tooth plates, is one of the largest chimaeroid fish known.