First rostrum of carnivorous Vitakridrinda (Abelisaurid Theropod Dinosaur) found from the latest Cretaceous Dinosaur Beds (Vitakri) Member of PAB formation, Alam Kali Kakor Locality of Vitakri area, Barkhan District, Balochistan, Pakistan

Abstract

The finding of rostrum of Vitakridrinda theropod dinosaur is the first one from Pakistan. It is found from the the Latest Cretaceous Dinosaur beds/Vitakri member of upper part of Pab Formation in Alam Kali Kakor locality of Vitakri region, Barkhan District, Balochistan, Pakistan. The newly discovered rostrum consists of articulated premaxilla alongwith narial, dorsolateral and lateral processes; external naris; partial nasal, palate and maxilla. The subterminal rostrocaudally subcircular nares, V shape of anterior snout and teeth characters representing pleisiomorphies of theropods. The ornamentation like pits and grooves on the surface of rostrum is the synapomorphy of abelisaurids. Many autopomorphies and other different useful characters of this rostrum are described here. The external nares seem to be bounded by the premaxilla only. The palate is well exposed at cross section. This snout is found in the site of previously reported basioccipital condyle articulated with partial braincase and a pair of proximal femur of Vitakridrinda. Although fragmentary these three masses associate and belong to one animal. This specimen will facilitate comparisons with the Gondwanan as well as Laurischian forms. It has bite mark, puncture, teeth impression and the embedded teeth revealing confrontation between Vitakridrinda and its combatant belonging to same or different species. The skull parts of this theropod are found with the partial skull of adult/subadult titanosaurs. Its occurrences with adult/subadult titanosaur suggest that the theropod came to the titanosaur animnal for feed subsequent fighting with other theropod cauld cause its death. The discovery of Vitakridrinda abelisaurids, alongwith saltasaurids, and baurusuchid from Pakistan broadens the distribution and indicates a close affinity with South America, Madagascar and India of Gondwanaland. These assemblages underscore many taxonomical features useful for paleobiology, paleobiogeography, phylogeny, behaviour like fighting, scavenging, predatory and, interaction among other species.