Cranial anatomy and phylogenetic position of the titanosaur sauropod Bonitasaura salgadoi

PABLO A. GALLINA; SEBASTIÁN APESTEGUÍA

ACTA PALAEONTOLOGICA POLONICA

INST PALEOBIOLOGII PAN

Lugar: Varsovia; Año: 2011 p. 45 - 60

0567-7920

The knowledge of titanosaur cranial anatomy has improved substantially in the last decade because several skulls have come to light or were restudied. The finding of Bonitasaura salgadoi, a partial titanosaur skeleton including cranial bones, permitted the definitive recognition of square jaws in titanosaur sauropod as well as a peculiar skull morphology which increases the morphological diversity of the group. Herein, a full description and illustration of skull materials of B. salgadoi is presented. Among cranial bones, the lacrimal, quadrate and dentary show strong differences with those of other titanosaurs. Conversely, the frontal and parietal are more conservative. A phylogenetic analysis portrays B. salgadoi as a member of Titanosauria, related with the mid to large–size titanosaurids from the Turonian–Campanian of South America, avoiding previous hypothesis that suggested a nemegtosaurid affinity. A skull restoration of B. salgadoi is provided, discussed, and compared with restorations of other related taxa.