Monday, November 2, 2020

[Paleontology • 2021] Leptostomia begaaensis • A Long-billed, Possible Probe-feeding Pterosaur (Pterodactyloidea: ?Azhdarchoidea) from the mid-Cretaceous of Morocco, North Africa


 Leptostomia begaaensis 

Smith, Martill, Kao, Zouhri & Longrich, 2021
Illustartion: Nick Longrich
 
Abstract
The pterosaurs were the first vertebrates to evolve powered flight and they staged a major radiation in the Cretaceous. Cretaceous pterosaurs occupied many of the niches occupied today by birds, including aerial insect hawkers, piscivores, and filter feeders. The diversity of this radiation remains poorly known due to the uneven stratigraphic and geographic distribution of pterosaur fossils. Much of what is known about pterosaur diversity comes from a handful of Lagerstätten, representing primarily lacustrine, lagoonal, and marine palaeoenvironments, primarily in Laurasia. These sites may fail to capture pterosaur diversity in other habitats and regions, such as Gondwana. Here, we describe a unique small, long-beaked pterosaur from fluvial mid-Cretaceous (?Albian–Cenomanian) strata of Morocco, North Africa, with adaptations for sediment probing. The upper and lower jaws form a hyperelongate dorsoventrally flattened beak, with thickened bony walls. The morphology most closely resembles that of probing birds such as kiwis, ibises, and curlews that probe in mud or earth for invertebrates. The affinities of the new pterosaur are unclear. It likely represents an azhdarchoid, but does not clearly fit within any known azhdarchoid clade. The new pterosaur adds to the remarkable diversity of pterosaurs known from the mid-Cretaceous, and suggests that pterosaur diversity remained under sampled.

Keywords: Pterosauria, Probe-feeding, Cretaceous, Morocco, Kem Kem Group

Fig. 2. Holotype partial rostrum of Leptostomia begaaensis gen. et sp. nov. FSAC-KK 5075.
A, dorsal; B, ventral; C, right lateral; D, left lateral; E, anterior end; F posterior end.
Scale bar A-D represents 5 mm; E-F represents 1 mm. 
Artwork by Julian Kiely. 



Systematic palaeontology
 PTEROSAURIA Kaup, 1834
 MONOFENESTRATA Lü et al., 2009
 PTERODACTYLOIDEA Plieninger, 1901
 LOPHOCRATIA Unwin, 2003
 AZHDARCHOIDEA Unwin, 1992
 ?Family unknown 

Leptostomia gen. nov.

Etymology: Leptos Gr. slender; stoma Gr. mouth.

 Leptostomia begaaensis gen. et sp. nov.

Etymology: After the oasis village of Hassi El Begaa near the type locality of Aferdou N’ Chaft.

Holotype. FSAC-KK 5075. Partial rostrum, anterior to nasoantorbital fenestra and missing tip

Type locality. Aferdou N'Chaft, Hassi El Begaa, Province d'Errachidia, Morocco. 

Type horizon and stage. Upper Ifezouane Formation, Kem Kem Group, ?Albian — lower Cenomanian.




Roy E. Smith, David M. Martill, Alexander Kao, Samir Zouhri and Nicholas Longrich. 2021. A Long-billed, Possible Probe-feeding Pterosaur (Pterodactyloidea: ?Azhdarchoidea) from the mid-Cretaceous of Morocco, North Africa. Cretaceous Research. 118: 104643. DOI: 10.1016/j.cretres.2020.104643