Kryptops

 Kryptops  (meaning "covered face", in reference to evidence that the face bore a tightly-adhering covering) is a genus of theropod dinosaur from the Early Cretaceous of Niger. It is known from a partial skeleton found at the Gadoufaoua locality in the western Ténéré Desert, in rocks of the Aptian-Albian age Elrhaz Formation. This dinosaur was described by Paul Sereno and Stephen Brusatte in 2008, with a single species to date: the type species K. palaios ("old").

Discovery
The holotype skeleton, MNN GAD1, includes a maxilla (main tooth-bearing bone of the upper jaw), vertebrae, ribs, and articulated pelvic girdle and sacrum, belonging to an adult about 6 to 7 meters long (20 to 23 ft). According to the describers, this specimen represents one of the earliest known abelisaurids, and is notable for the heavily textured surface of the maxilla; the presence of pits and impressions of blood vessels indicates that there was a covering firmly attached to the face, perhaps of keratin. Sereno and Brusatte performed a cladistics analysis that found Kryptops to be the most basal abelisaurid. This was based on several features, including a maxilla textured externally by impressed vascular grooves and a narrow antorbital fossa, that clearly place Kryptops palaios within Abelisauridae as its oldest known member.[1] Carrano et al., on the other hand, consider Kryptops palaios to be a chimera, and state that its postcranial remains (especially a pelvis and sacrum), found some 15 metres from the holotypic maxilla, actually belong to a carcharodontosaurid (possibly to Eocarcharia dinops).