Monday, November 22, 2010

Butterfly Lizards, Recent Developments


Their bright coloration probably accounts for the common name ― the Butterfly Lizards, for members of the genus Leiolepis . The Butterfly Lizards are found from southern China, Vietnam, Laos, Cambodia, Myanmar, and Thailand southwest through Peninsular Malaysia. Of interest are early suggestions that Leiolepis ‘glides’ from trees (Cantor, 1847). And, Swinhoe (1870) wrote, that “if surprised far from their holes, they spring into the air while running, and, expanding the loose red skin of their sides, skim along the surface of the sand for a considerable distance (say, often 20 yards at a time) and thus reach their retreats at greater speed.” Probably because of these comments in the literature Edward Taylor suggested they “sail” off banks. Losso et al. (1988) measured locomotor performance of Leiolepis belliani running, jumping and parachuting and investigated whether performance capabilities are correlated with morphological features. They also examined the ability of this lizard to flatten its body. Larger lizards fell and ran faster and jumped further. Lizards that were experimentally prevented from flattening fell faster than control lizards. Cantor and Swinhoe comments were apparently exaggerated because a number of other observers have failed to see the behavior and found these lizards only able to run. Losso et al.(1988) concluded that it is unlikely that lateral flattening has evolved as an adaptation for parachuting in Leiolepis, However, they suggest the ability of Leiolepis to flatten its body may function in: thermoregulation; intraspecific communication (male butterfly lizards have brightly marked flanks), and lateral flattening has been observed during male combat. Or, Leiolepis may have evolved the flattening ability to startle predators.

The seven known species of Southeast Asian Buttererfly Lizards have been long considered to belong to the family Agamidae. Four of the seven species are sexually reproducing species: Leiolepis belliana (Gray, 1827); L. guttata Cuvier, 1829; L. peguensis Peters, 1971; and L. reevesii Gray, 1831); and the other three species reproduce asexually (L. boehmei Darevsky and Kupriyanova, 1993; L. guentherpetersi Darevsky and Kupriyanova, 1993, and L. triploida Peters, 1971).

Now, Grismer and Grismer (2010) have described a new asexual species from Binh Chau – Phuoc Buu Nature Reserve, in Vietnam where it is believed to be endemic. The new species, Leiolepis ngovantrii differs from all sexual species of Leiolepis by lacking males and from all asexual species by having nine rows of enlarged keeled scales across the forearm. Grismer and Grismer made phylogenetic inferences based on 700 base pairs of the mitochondrial ND2 region, and suggest L. ngovantrii's maternal ancestor was L. guttata, and found it was also the ancestral species of L. guentherpetersi, L. boehmei, and L. ngovantrii. L. boehmei was recovered as the maternal ancestor to L. triploida. Leiolepis is also of interest because they are often eaten by humans. Recent news reports (November 12,2010) are reporting that the Vietnamese are serving the just described, fast moving, L. ngovantrii in restaurants despite the fact that it is believed to be restricted to the Binh Chau-Phuoc Buu Nature Reserve. While it might be news that the newly described species is being eaten, it has been relatively well known that other members of the genus also find themselves in the kitchens of Southeast Asia.

As for the relationship of the Butterfly Lizards to other lizards, the studies have been a bit confusing. But, Okajima and Kumazawa (2010) have recently used the mtDNA genomes of agamid lizards to sort out relationships and found that within Agamidae, Uromastyx (Uromastycinae) diverged first and Leiolepis  (Leiolepidinae) diverged next. The Uromastycinae and Leiolepidinae are found to be sister to each other, forming a basal clade in the agamids.

Literature
Cantor, T. 1847. Catalogue of reptiles inhabiting the Malayan peninsula and islands, collected or observed by Theodore Cantor, Esq., M.D. Journal of the Asiatic Society of Bengal 16:607-656, 896-951, 1026-1078.

Grismer, J. L. and L. Grismer. 2010. Who’s your mommy? Identifying maternal ancestors of asexual species of Leiolepis Cuvier, 1829 and the description of a new endemic species of asexual Leiolepis Cuvier, 1829 from Southern Vietnam. Zootaxa 2433: 47–61.

Okajima, Y. and Y. Kumazawa. 2010. Mitochondrial genomes of acrodont lizards: timing of gene rearrangements and phylogenetic and biogeographic implications. BMC Evolutionary Biology 10:141. http://www.biomedcentral.com/1471-2148/10/141.

Srikulnath, K., K. Matsubara3, Y. Uno, A. Thongpan, S. Suputtitada, C. Nishida, Y. Matsuda, and S. Apisitwanich1. 2010. Genetic Relationship of Three Butterfly Lizard Species (Leiolepis reevesii rubritaeniata, Leiolepis belliana belliana, Leiolepis boehmei, Agamidae, Squamata) Inferred from Nuclear Gene Sequence Analyses. Kasetsart Journal (Natural Science) 44: 424-435.

Swinhoe, R. 1870. List of reptiles and batrachians collected in the island of Hainan (China), with notes. Proceeding of the Zoological Society of London 1870: 239-241.




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