. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. C D E 0[ r ^^-17 #/' S© vv 1 jiijO X' ' i ' ^ 2lLL LJ ^iB. Figure 9. Anterior end of the dorsal armor, with selected precaudal scale rows numbered, PC 13 forward on: A. Osteolaemus tetraspis, USNM 193289. B. Alligator mississippiensis, MCZ 17723. C. A. sinensis, FMNH 38234. PC 17 forward on: D. Caiman crocodilus, MCZ 15334. PC 13 fonward on: E. C. latirostris, MCZ 3588. 19 to PC 24 to be accounted for by the three rows of the cervical shield a
. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. C D E 0[ r ^^-17 #/' S© vv 1 jiijO X' ' i ' ^ 2lLL LJ ^iB. Figure 9. Anterior end of the dorsal armor, with selected precaudal scale rows numbered, PC 13 forward on: A. Osteolaemus tetraspis, USNM 193289. B. Alligator mississippiensis, MCZ 17723. C. A. sinensis, FMNH 38234. PC 17 forward on: D. Caiman crocodilus, MCZ 15334. PC 13 fonward on: E. C. latirostris, MCZ 3588. 19 to PC 24 to be accounted for by the three rows of the cervical shield and the smaller nape row. The possibility of compounding is indicated by the large size of the anteriormost of the three rows of the cervical shield. Alligator mississippiensis In Alligator mississippiensis (Fig. 9B), the continuous and contiguous precaudal armor is five to eight, usually eight, scutes across at midbody, and there are no detached scutes on the flanks. The thoracic and cervical armors are barely continuous, having reduced elements in PC 18 to PC 19, and possibly PC 20, and two folds of skin in the cervico-thoracic juncture. PC 18 is ordinarily present as two small scutes. There are ordinarily lateral scutes which may be from PC 18 or traces of PC 19 (we don't know which). If PC 19 is absent on the midline, there are two scutes in PC 20, two very long elements in PC 21+22, two in PC 23, and then the nape scales. If the posteriormost neck scute is PC 19, PC 20+21 has two very long scutes, and PC 22+23 has two shorter scutes, and then there are the nape scutes in two or three rows separat- ed on the midline. The most prominent nape row is PC 25, ordinarily with two, but with up to six ossified elements. PC 25 is the postoccipital of Ross and Roberts (1979); in Crocodylus this term refers to PC 26. Caiman latirostris In Caiman latirostris (Fig. 9E) the con- tinuous and contiguous precaudal armor varies from regular to somewhat irregular in the alignment of the keels
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Keywords: ., bookauthorharvarduniver, bookcentury1900, booksubjectherpetology
