Literaturdatenbank
Literaturdatenbank |
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Bertl, J., & Killebrew, F. C. (1983). An osteological comparison of graptemys caglei haynes and mckown and graptemys versa stejneger (testudines: Emydidae). Herpetologica, 39(4), 375–382.
Added by: Admin (06 Jan 2014 18:22:38 UTC) |
| Resource type: Journal Article BibTeX citation key: Bertl1983a View all bibliographic details  |
Categories: General Keywords: Emydidae, Graptemys caglei, Graptemys flavimaculata, Graptemys nigrinoda, Graptemys versa, Schildkröten - turtles + tortoises, Systematik - taxonomy Creators: Bertl, Killebrew Collection: Herpetologica |
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| Abstract |
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Skeletons of Graptemys caglei and Graptemys versa of the Guadalupe and Colorado rivers of Texas, respectively, are compared. G. caglei and G. versa differ in color pattern, morphology of the vertebral spines, and eight significant osteological characters. Osteological divergence is noted in the relative contribution of the jugal to the orbit, the shape of the rostral projection of the basisphenoid, the shape of the basisphenoid-basioccipital suture, the conformation of the ventral border of the apertura nervi trigemini, the shapes of the supraoccipital, the nature of the contact between the palatine process of the premaxilla and the vomer, and the presence or absence of a posterior process on the coracoid. The presence of a prefrontal process on the frontal, lack of broadening of the alveolar surfaces, and lack of excessive shelving on the parietals, supraoccipital, squamosals, and postorbitals support inclusion of G. caglei and G. versa in the "narrow-headed" Graptemys species group. Sexual maturity in both species is attained at a carapace length of 60 mm, unlike G. flavimaculata and G. nigrinoda (80 mm). Sexual dimorphism in the basioccipital and supraoccipital is displayed in both G. versa and G. caglei. The sexual dimorphism described for the supraoccipital is the same as that previously described for G. flavimaculata and G. nigrinoda.
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