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

GOURIC-CAVALLI, S.; CABRERA, D.; CIONE, A.; O´GORMAN, ; CORIA, R.; FERNÁNDEZ, M.

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 acomplete dentition collected in the late Campanian Herbert Sound Member of the Snow Hill Island Formation of JamesRoss Island, Antarctica. The dentition consists of paired vomerine, mandibular, and palatine tooth plates, which are almostcompletely preserved. The new species is characterized by a unique character combination out of which the presence of asubquadrangular vomerine tooth plate and a horse-hoof-shaped anterior outer tritor in the mandibular tooth plates appear tobe unique characters among the edaphodontids. Edaphodon snowhillensis, sp. nov., represents the most complete dentition ofa holocephalian fish from the Southern Hemisphere and the earliest record of the genus Edaphodon from the Antarcticcontinent and the Weddellian Biogeographic Province. Also, E. snowhillensis, sp. nov., is the southernmost specimen of thisgenus and according to the size of the tooth plates is one of the largest chimaeroid fish known.