Karyotypes of Four Agamid Lizards from Southeast Asia.

Abstract

We karyotyped four lizards, Acanthosaura armata, Bronchocela cristatella, Calotes emma, and C. versicolor, all belonging to the tropical Asian Glade of the family Agamidae. The karyotype of A. armata consisted of 12 metacentric macrochromosomes and 20 microchromosomes, whereas B. cristatella had 14 metacentric macrochromosomes and 20 microchromosomes. Except for the presence of 22 microchromosomes, the karyotypes of the two Calotes species were similar to that of A. armata. The 20 microchromosome state in the A. armata karyotype may have emerged in the ancestral lineage common to Gonocephalus robinsonii, whose karyotype also exhibits a 12M+20m format. Comparison of the present results with previously published information suggests the presence of cryptic taxonomic diversity in B. cristatella and C. versicolor.

Karyological Analysis of the Indo-Chinese Water Dragon, <i>Physignathus cocincinus</i> (Squamata, Agamidae) from Thailand

“…One of these karyomorphs is considered to be derived from the other through a series of Robertsonian rearrangements (centric fusion) of macrochromosomes, sometimes accompanied with addition or deletion of one microchromosome pair (Bickham 1984, Diong et al 2000. The karyotypes of the sex chromosome of males and females are not different in contrast to the karyotypes of other agamid lizards (Diong et al 2000, Ota et al 2002, Srikulnath et al 2009). Morphologically differentiated sex chromosomes have been described in only two species of agamid lizards, Phrynocephalus vlangalii and Pogona vitticeps.…”