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Archives of The Cold Blooded NewsThe Newsletter of the Colorado Herpetological SocietyVolume 29, Number 10; October, 2002 |
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Beautiful Loser Jaws Too Hard to Swallow? Jaw Bumps Help Gators Frog Poison Sunbeam Snake Backyard Pond Federal Plan Set Whiptails Next Issue November 2002 PREVIOUS ISSUES September 2002 August 2002 July 2002 June 2002 May 2002 April 2002 March 2002 February 2002 January 2002 Earlier Issues About the Cold Blooded News CHS Home Page |
Whiptail SystematicsReprinted from the Bulletin of the Chicago Herpetological Society, Vol.37, No.7, July 2002.T. W. Reeder et al. [2002, American Museum Novitates 3365] infer phylogenetic relationships of the whiptail lizards of the genus Cnemidophorus based on a combined analysis of mitochondrial DNA, morphology and allozymes. Within the Teiini, Teius and Dicrodon are the most basal lineages, and these two taxa form a graded series leading to a cnemidophorine clade containing Ameiva, Cnemidophorus, and Kentropyx. Cnemidophorus monophyly is not supported, with members of the Neotropical "C." lemniscatus species group (except "C." longicaudus) being more closely related to species in other Neotropical cnemidophorine taxa (Ameiva and Kentropyx). Ameiva is also paraphyletic. Because of Cnemidophorus paraphyly, nomenclatural changes are recommended. Aspidoscelis Fitzinger, 1843, is resurrected for the North American "Cnemidophorus" clade containing the deppii, sexlineatus, and tigris species groups (and the unisexual taxa associated with them). Lizards of the genus Aspidoscelis differ from all other cnemidophorine lizards by the combined attributes of absence of basal tongue sheath, posterior portion of tongue clearly forked, smooth ventral scutes, eight rows of ventral scutes at midbody, absence of anal spurs in males, mesoptychial scales abruptly enlarged over scales of gular fold (more anterior mesoptychials becoming smaller), three parietal scales, and three or four supraocular scales on each side. A review of current knowledge of teioid unisexuals and their hybrid origins is provided. Also, a reevaluation of teiine chromosomal evolution is presented from a phylogenetic perspective. These reviews elucidate the paradox that the capability of instantly producing parthenogenetic clones through one generation of hybridization has existed for approximately 200 million years, yet the extant unisexual taxa are of very recent origins. Consequently, these lineages must be ephemeral compared to those of bisexual taxa. Copyright © 1998 - 2006, Colorado Herpetological Society. All rights reserved. | ||
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