Osseous anomalies of the cryptobranchid <i>Eoscapherpeton asiaticum</i> (Amphibia: Caudata) from the Late Cretaceous of Uzbekistan

Osseous anomalies/pathologies in the Late Cretaceous cryptobranchid salamander Eoscapherpeton asiaticum from the Turonian Bissekty Formation of Uzbekistan are analyzed using gross morphological description, microCT, and histologic analysis. These pathologies result from trauma (fractured and subsequently healed dentary and femora; hematoma on femur), possible infection due to trauma (prearticular with exostosis and necrotic cavities; anterior trunk vertebra and fused vertebra with pathological enlargements formed during reactive periosteal growth) and congenital disorders (hemivertebra and fused vertebrae with shortened asymmetrical centra and abnormal arrangements of transverse processes). The origin of the pathologies of two atlantal specimens (enlargement of transverse processes) is unclear. Our report of hemivertebra in Eoscapherpeton is the first occurrence of this congenital pathology in a fossil lissamphibian. The occurrence of several traumatic femoral pathologies in Eoscapherpeton could be a result of intraspecific aggressive behavior. Bone pathologies are described for the first time in fossil salamanders.

A Bestiary—Annotated Taxonomic Accounts

This chapter consists of annotated taxonomic accounts of Pleistocene amphibians and reptiles recorded from the study area (see Fig. 1). General external characters, habits, and distributional patterns of modern taxa of amphibians and reptiles that occur in the British and European Pleistocene in this and following chapters are from the author's unpublished field notes and photographs as well as the following sources: Arnold and Burton (1978), Ballasina (1984), Beebee (1983), Berger et al. (1969), Duellman (1993), Duellman and Trueb (1986), Engelmann et al. (1986), Ernst and Barbour (1989), Escriva (1987), Estes (1981, 1983), Frazer (1983), Frost (1985), Gunther (1996), Halliday and Adler (1986), Hellmich (1962), Hvass (1972), King and Burke (1989), Matz (1983), Noble (1931), Smith (1964), Sparreboom (1981), and Zug (1993). The reader is cautioned not to attempt to identify Pleistocene amphibian and reptile fossils solely on the basis of skeletal characters discussed or skeletal figures presented in this book—or in other publications. To identify Pleistocene amphibian and reptile fossils accurately, it is necessary to compare them with adequate modern and fossil skeletal material. Pleistocene locality numbers below correspond with locality numbers in Chapter 5. Pleistocene caudate amphibians are usually identified on the basis of individual trunk vertebrae (see Holman, 1995c, p. 83). Figure 3 illustrates the important features of a trunk vertebra of Triturus cristatus from the Middle Pleistocene of Cudmore Grove, Essex, England.