Tuesday, December 7, 2021

[Paleontology • 2021] A Large Pterosaur Femur (Pterosauria: Dsungaripteroidea) from the Kimmeridgian, Upper Jurassic of Lusitanian Basin, Portugal


 Pterosaur from the Kimmeridgian, Upper Jurassic of Lusitanian Basin, Portugal

in Bertozzo, Da Silva, Martill, et al., 2021. 
Artwork by Joschua Knüppe twitter.com/JoschuaKnuppe 

The pterosaur fossil record in Portugal is scarce, comprising mainly isolated teeth and rare postcranial material. Here,we describe a well-preserved right proximal femur of a pterodactyloid pterosaur from the Kimmeridgian, Upper Jurassic Praia da Amoreira–Porto Novo Formation of Peniche, Portugal. It is noteworthy for its relatively large size, compared toother Jurassic pterosaurs. It shows affinities with dsungaripteroids based on a combination of features including the bowing of the shaft, the mushroom-like cap of the femoral head, and the distinctly elevated greater trochanter. The femur hasa relatively thinner bone wall compared to dsungaripterids, and is more similar to basal dsungaripteroids. A histological analysis of the bone cortex shows it had reached skeletal maturity. The preserved last growth period indicates fast, uninterrupted growth continued until the final asymptotic size was reached, a growth pattern which could best be compared to pterodactyloid femora from the Early Cretaceous. The specimen is the second confirmed report of a dsungaripteroid from the Jurassic, and it is the first record of this group from the Iberian Peninsula.

Key words: Pterosauria, Dsungaripteroidea, histology, Late Jurassic, Kimmeridgian, Portugal.

A partial proximal right femur of a large indeterminate dsungaripteroid pterosaur (SHN.013) from the Kimmeridgian, Upper Jurassic, Praia da Armoreira-Porto Novo Formation, Peniche, Portugal.
 In ventral (posterior) (A1), dorsal (anterior) (A2), medial (A3), lateral (A4), distal (A3), and proximal (A6) views; A7, drawing of the distal end showing the thickness of the cortex compared to the lumen. Note that the sketch is about twice the scale of the images. The red dashed lines in A2 and A3 indicate the site where the histological section was taken.


Pterosauria Kaup, 1834 
Monofenestrata Lü, Unwin, Jin, Liu, and Ji, 2009 
Pterodactyloidea Plieninger, 1901 

Dsungaripteroidea Young, 1964 (sensu Unwin 2003) 

Dsungaripteroidea indet.

SHN.013



Filippo Bertozzo, Bruno Camilo Da Silva, David Martill, Elsa Marlene Vorderwuelbecke, Tito Aureliano, Remmert Schouten, and Pedro Aquino. 2021. A Large Pterosaur Femur from the Kimmeridgian, Upper Jurassic of Lusitanian Basin, Portugal. Acta Palaeontologica Polonica.  in press. DOI: 10.4202/app.00858.2020

CI2Paleo, Sociedade de Historia Natural, Travessa Florêncio Augusto Chagas nº8B, R/C, 2560-230 Torres Vedras, Portugal.