Ophiuroidea (Echinodermata) from the Central Mexican Pacific: an updated checklist including new distribution records

Abstract

The Central Mexican Pacific is an oceanographic transitional region with complex habitats and important conservation areas, but knowledge of its Ophiuroidea fauna is limited. A total of 61 localities on a variety of substrata were sampled between 2008 and 2014 using different methodology techniques. Twenty-four species were collected and members of the families Ophiocomidae, Ophiotrichidae and Ophiactidae were the most widespread. The new records of 28 species have relevance in terms of filling distribution gaps along the Mexican Pacific or extending their geographical distribution ranges. This considerable number can be attributed to a higher number of prospected localities and the diversification of collecting methods. An updated checklist from the study area is provided, including previous literature records and those found during this work, summarising 57 species. Islas Marias was the area with the highest number of species and with the highest value of taxonomic distinctness, which can be explained since these islands are considered as stepping stones for the dispersal of species in the Mexican Pacific. Despite the important diversity and composition of ophiuroids in our study area, a sample-based rarefaction curve suggests that at least 104 species can inhabit the area, so we recommend conducting more research in the region.