I was recently asked for a few drawings representing the late cretaceous fauna found in the Coahuila province of Northeastern Mexico. The last decade indeed saw some interesting discoveries there including the hadrosaur Velafrons, a large but not fully described species of Kritosaurus (unofficially baptized “Sabinosaurio”) and the ceratopsian Coahuilaceratops which have the largest horns on record among the dinosaurs (this might be a subject of an upcoming post, so stay tune).
Fig 1.- A pair of Muzquizopteryx at sunset
This was a good opportunity for me to get into that peculiar group of pterosaurs called Nyctosaurids. The medium size Muzquizopteryx coahuilensis from the Late Cretaceous of Coahuila is known from a relatively complete articulated skeleton missing the front of the skull and the ends of the wings and feet (a picture of the fossil can be found here). The name somehow reminds me of mosquitoes and I first imagined tiny pterosaurs buzzing among gigantic hadrosaurs, but the wingspan was actually close to 2 meters (the name refers to the county, Múzquiz, where the fossil was found).
Fig 2.- Close up view of Muzquizopteryx.
Nyctosaurids show adaptation to an aerial lifestyle pushed to the extreme. They have lost the three-clawed fingers characterizing other pterosaurs, with only the wing finger remaining and their feet were relatively small, indicating that they would fare very badly on the ground so probably spent most of their time in the air. The remaining body characteristics and proportions are comparable to those of the related pteranodontids (Pteranodon and friends). After Muzquizopteryx, how could you resist representing the amazing Nyctosaurus from the Niobrara chalk of Kansas with its large antler-like crest that is apparently present only on adults and the function of which is still unclear.
Fig 3.- Nyctosaurus over the Western Interior Seaway.
Bennett, S.C. 2003. "New crested specimens of the Late Cretaceous pterosaur Nyctosaurus." Paläontologische Zeitschrift, 77: 61-75.
Frey, E., Buchy, M.-C., Stinnesbeck, W., González, A.G., and di Stefano, A. 2006. “Muzquizopteryx coahuilensis n.g., n. sp., a nyctosaurid pterosaur with soft tissue preservation from the Coniacian (Late Cretaceous) of northeast Mexico (Coahuila)”. Oryctos 6:19-39.