Anolis capito Peters, 1863

Castiglia, Riccardo, Flores-Villela, Oscar Alberto, Bezerra, Alexandra M. R., Gornung, Ekaterina, Annesi, Flavia, Munoz-Alonso, Luis Antonio & Solano, Emanuela, 2020, Detection of cryptic diversity in lizards (Squamata) from two Biosphere Reserves in Mesoamerica, Comparative Cytogenetics 14 (4), pp. 613-638 : 613

Anolis capito Peters, 1863

Distribution.

Anolis capito has been found from Tabasco and northern Chiapas south to Central America on the Atlantic coast, to Costa Rica and Panama, where it is found on both coasts.

Samples.

RCMX217 (female*), RCMX218 (female*) from Montes Azules, Chiapas, Mexico. The specimens were collected close to the northern part of species range and morphologically assigned to Anolis capito . Based on morphological studies from populations of almost all the species range, there is no evidence of cryptic species in A. capito ( Köhler et al. 2005).

DNA taxonomy.

We obtained a 685-bp MT-ND2 sequence showing 9% genetic divergence respect to an A. capito sequence collected in Costa Rica (GenBank AY909744). Such a high genetic divergence spurred us to perform a complete phylogenetic analysis with the MT-ND2 gene of Anolis species available in GenBank (not shown). The sequences from our samples cluster with the GenBank A. capito sequence, and together were sister to A. tropidonotus Peters, 1863. This tree topology has been already reported by Poe et al. (2017). Summarizing, the very high genetic divergence and discrepancies in diploid chromosome numbers (see below) of morphologically similar individuals recognized as Anolis capito indicate the possible existence of cryptic taxa. Further, it is worth noting that the specimens described here seem to have shorter limbs than other A. capito (O. Flores-Villela personal observation).

Chromosomes.

Gorman (1973) described the karyotype of Anolis capito , under the name of Norops capito , as 2n = 40 (24M + 16m) with no evidence of heteromorphic sex chromosomes, but no details on the shape of the chromosomes were reported. Our specimens have a 2n = 42 chromosome complement, with 24 micro- and 18 microchromosomes, and no evidence of heteromorphic sex chromosomes but no males have been studied (Fig. 6A ).

The specimens presently studied show, along with Anolis nebuloides Bocourt, 1973, the highest diploid number within the genus Anolis . The macrochromosomes include one pair of metacentric, six pairs of submetacentric, and five pairs of subtelocentric/acrocentric chromosomes. The chromosome shape of two pairs of microchromosomes appears to be biarmed. No heteromorphic sex chromosomes are discernible (unfortunately, no males have been analyzed).

The lack of description of chromosome morphology in Gorman’s study ( Gorman 1973) did not allow detailed comparison among the 2n = 40 chromosomal complements. Thus, Anolis capito occurs within a group of species with 2n = 40 ( Castiglia et al. 2013b) and its additional chromosomal pair is probably due to a fission event. It has already been hypothesized that chromosomal fission is a characteristic trait of Norops chromosome evolution ( Castiglia et al 2013b; Gamble et al. 2014).

Figures

Figure 6. Bayesian phylogenetic tree (A) and TCS network (B) of 16 S haplotypes belonging to Lepidophyma flavimaculatum. The colors refer to the geographic provenience of individuals. In bold, the new specimens from this study.