A new pterosaur mandible from the Lower Cretaceous of Brazil, and its implications on the taxonomy of the genus Anhanguera (Pterosauria, Anhangueridae)

Abstract

Pterosaurs are extinct archosaurs specialized in an active flight lifestyle, with more than half of the species described classified as pterodactyloids. Much of the anatomical knowledge on pterodactyloids originated from specimens collected in the Cretaceous deposits of South America. The Araripe Basin in Northeastern Brazil holds a remarkable record, particularly within the Aptian–Albian Crato and Romualdo formations, from which numerous specimens have been assigned to the genus Anhanguera. To date, three species from this unit are recognized as valid based on relatively complete specimens: A. blittersdorffi, A. piscator, and A. spielbergi. Here, we describe a new anhanguerid specimen from the Romualdo Formation, comprising an almost complete lower jaw and elements of the hyoid apparatus. MZSP-PV 368 is assigned to Anhanguera based on the presence of a well-developed ventral mandibular crest, specific alveoli count, and tooth morphology. The specimen has an overall shape of the crest that is unique among ornithocheiromorphs and supports its referral to A. robustus, a species recently considered a nomen dubium. Phylogenetic and morphometric analyses of MZSP-PV 368 further support its affinity with A. robustus, highlighting the diagnostic value of mandibular crest morphology in anhanguerid taxonomy. These findings indicate that A. robustus represents a diagnosable taxon, herein recognized as a valid species. However, the taxonomy of the genus Anhanguera remains unresolved and will require additional specimens with a greater degree of anatomical overlap for further clarification.