Ixchela azteca (Araneae: Pholcidae), a widespread spider species from Central Mexico: Underestimated diversity or morphological and genetic variation?
DOI:
https://doi.org/10.22201/ib.20078706e.2025.96.5466Keywords:
Delimitación de especies, Taxonomía integrativa, CO1, Ecología, Provincias biogeográficasAbstract
We describe the morphological and genetic variation in Ixchela azteca Valdez-Mondragón & Francke from central Mexico, based on morphology and DNA barcoding of the cytochrome c oxidase subunit 1 (CO1) mitochondrial marker. Molecular analyses of species delimitation included three methods under the corrected genetic p-distances neighbor-joining (NJ) criteria: 1) Assemble Species by Automatic Partitioning (ASAP), 2) General Mixed Yule Coalescent model (GMYC), and 4) Bayesian Poisson Tree Processes (bPTP). The genetic analyses between two populations of I. azteca found a genetic p-distance of 3.5%. The molecular methods and morphology were not congruent in delimiting and recognizing two possible different species, but two allopatric populations of I. azteca are recognized. In conclusion, the incongruence of the molecular delimitation methods for species delimitations in combination with the morphology, genetic, ecological, and biogeographical evidence, corroborates to I. azteca as a widespread species in central region of Mexico, with allopatric populations in temperate but also semiarid regions.
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