Morphology, diversity, and distribution of the Cyclopoida (Copepoda) from arid areas of central-north. Mexico. II. Eucyclopinae and biogeographic analysis

Abstract

This work represents a continuation of a previous article about the cyclopoid copepod fauna in arid areas of northcentral Mexico, in this case about the subfamily Eucyclopinae. From samples previously collected (1985-2008) and from new samples, we reviewed the eucyclopine copepod fauna from this vast arid area of Mexico. Three priority ecoregions (CONABIO) were included, comprising part of the states of Aguascalientes, Zacatecas, San Luis Potosí, Durango, Chihuahua, and Coahuila. Up to 22 species of the Eucyclopinae were found, among which 18 are new state records. Diagnoses and taxonomic illustrations of the species recorded are provided together with a comparative analysis of the specimens examined. The records reported in this paper plus those previously published on the subfamily Cyclopinae, represented a 20% increase in the list of species of Cyclopoida from inland waters present in Mexico. An overall biogeographic analysis of the Cyclopoida was performed; it shows a high degree of endemism in this region (20%), similar to that detected for the group in the Yucatan Peninsula (19%). Using a Similitude Analysis (Jaccard) we found that the fauna of the northern arid areas is very similar to that of central Mexico and southern United States. Another group was formed by the Caribbean, Central America, and southern Mexico. There is a considerable divergence between the South American cyclopoid fauna with the rest of the continent.