A new species of killifish of the family Profundulidae from the highlandsof the Mixteca region, Mexico

Resumen

The family Profundulidae is one of the few families of freshwater fishes endemic to the Mesoamerican region. It includes the genus Profundulusthat has been divided into two subgenera, Profundulus, with a wider distribution and Tlaloc, which presents a more limited range. The speciescurrently recognized within the subgenus Profundulus are P. punctatus, P. oaxacae, P. guatemalensis and P. kreiseri. Results from a previous studyusing allozymes revealed a high degree of molecular differentiation of the populations inhabiting the Mixteca region (located at the north of Oaxacain Mexico), compared to the rest of the species in the genus, especially regarding its geographically nearest neighbor (P. oaxacae). The main goalof this study was to evaluate the morphological distinctiveness and to assess the taxonomic identity of the populations from the Mixteca regionin comparison with the morphological variation of P. oaxacae. Based on 22 measurements (17 morphometric and 5 meristic), we examined themorphological variation within and among species, including 50 individuals from 5 localities. Our results show a high degree of morphologicaldifferentiation between both populations in accordance to the molecular information reported before, supporting that populations from the Mixtecaregion are a new taxonomic entity, which is described in the present study.