Molecular cytogenetics markers reveal the existence of a cryptic complex of Mazama temama species

Abstract

Mazama temama, commonly named Central American red brocket deer, was described in Veracruz, east-central México. Cytogenetic studies have characterized differentiated karyotypes observed in captive individuals of the species with a diploid number (2n) = 49 to 50, in a recently collected neotype with a diploid number (2n) = 44 and fundamental number (FN) = 70, and in specimens collected in Campeche in the southeast of México with a diploid number (2n) = 47 and fundamental number (FN) = 70. Then, we used BAC probes derived from cattle genome aiming to describe the chromosomal differences in M. temama karyotypic variants. We compared three individuals from Campeche (CAM) and the Veracruz neotype (VER). A total of 38 clones have been mapped by fluorescent in situ hybridization onto the chromosomes of both variants and a comparative map has been established. We assessed Cytochrome b (Cytb) gene sequences to perform phylogenetic analyzes including M. temama individuals from these localities and other Neotropical deer. The integrated analysis of hybridization results showed the real and surprising differences between the specimens. Besides the morphological similarities between the M. temama specimens, the results showed a difference of 10 chromosomes involved in rearrangements that separate their karyotypic composition, associated with tandem and centric fused chromosomes. Bayesian Inference tree evidenced Campeche and Veracruz individuals in two separated subclades within M. temama clade. The observed chromosomal and genetic differences are a substantially evidence of a reproductive isolation mechanism between the Veracruz and Campeche individuals suggesting the existence of a cryptic complex of species under M. temama nomenclature. Therefore, conservation strategies should be considered separately for each population of central American red brocket deer.