CERDA Ignacio Alejandro
Long-necked chelid turtles from the Campanian of northwestern Patagonia with comments on K/P survivorship of the genus Yaminuechelys
MARCELO DE LA FUENTE; IGNACIO MANIEL; MARCOS JANNELLO; LEONARDO S. FILIPPI; IGNACIO A. CERDA
COMPTES RENDUS PALEVOL
ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER
Lugar: Paris; Año: 2015 vol. 14 p. 563 - 563
tThe long-necked chelid turtle Yaminuechelys aff. maior is described on the basis of post-cranial material of two specimens from the Lower?Middle Campanian Anacleto Formation,nortwestern Patagonia (Argentina). These post-cranial remains are described macro-scopically (external morphology) and microscopically (histological sections of the shell).Although minor carapace and plastral differences are reported (e.g., extension of the axil-lary buttresses on visceral surfaces of the first costal bone, curled bridge peripheral bones,absence of a sub-rectangular fenestra retained in adults) the specimens exibit the shellmorphology and surface ornamentation of specimens referred to Y. maior (Staesche, 1929)from Paleocene levels of the Salamanca Formation (Central Patagonia). This assignment issupported by a phylogenetic analysis, in which the new material is the most closely relatedto Y. maior. As Yaminuechelys is hypothesized to be the sister taxon of Hydromedusa, thecapability of Hydromedusa tectifera to adapt to changing environments and the survivorshipof Yaminuechelys genus in K/P boundary is discussed.