A survey of pterosaurs from the Jurassic and Cretaceous of the former soviet union and Mongolia

Abstract

Remains of pterosaurs, the dominant aerial vertebrate throughout much of the Mesozoic were, until relatively recently, almost exclusively known from marine and marginal marine sediments of western Europe and North America. Prior to the 1960s Mesozoic deposits in the former Soviet Union and Mongolia had produced very few pterosaurs, but, in the last thirty years, many remains, including some from continental environments, have been found. Most important among these are Sordes and Batrachognathus from the Late Jurassic of Karatau in Kazakhstan, Azhdarcho from the Late Cretaceous of the Kyzylkum desert in Uzbekistan, and a number of new Mongolian pterosaurs, including a possible anurognathid from the Mid Jurassic of Bakhar, a dsungaripterid from the early Early Cretaceous of Tatal and an ornithocheirid from the late Early Cretaceous of Khuren‐Dukh. Although already documented to some extent, the significance of these discoveries remains underappreciated.

The discovery and collection of these pterosaurs is described and the bearing of some of the more important material on current problems of pterosaur biology is discussed. We confirm Sharov's observation that the hind limbs of Sordes form an integral part of the flight apparatus, attached externally to the cheiropatagium and internally to the uropatagium, which is supported and manipulated by the fifth toe. The former Soviet and Mongolian pterosaurs also help to fill a number of important morphological and temporal gaps in the pterosaur fossil record and provide the best available evidence of pterosaurs from continental environments. With the exception of insectivores, these and other continental pterosaurs appear to have pursued lifestyles similar to those of their marine counterparts, leading us to suspect that pterosaurs largely failed to exploit terrestrial habitats.

Key words:

• Soviet Union
• Mongolia
• Jurassic
• Cretaceous
• pterosaur
• functional morphology
• palaeoecology

Notes

Correspondence should be sent to: David M. Unwin, Department of Geology, University of Bristol, Queen's Road, Bristol BS8 1R J, U.K. Moscow‐Bristol Joint Palaeontological Programme, Contribution No. 13.

Currentaddress: Dept. of Geology, University of Bristol, Queen's Rood, Bristol BS8 IRJ, O.K.