Troglomorphism in the brittle star Ophionereis commutabilis Bribiesca-Contreras et al., 2019 (Echinodermata, Ophiuroidea, Ophionereididae)

By

Márquez-Borrás, Francisco
Solis-Marin, Francisco
Mejia-Ortiz, Luis

Type

Article

Date of Publication

2020

Original Publication

Subterranean Biology

Volume

33

Pages

87--108

Subjects

Adaptation , Aerolito , Anchialine system , cave , Cozumel , ophiuroid , stygobiotic

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/subtbiol.33.48721

 

Abstract

Due to their peculiar and sometimes bizarre morphology, cave fauna (across invertebrates and vertebrates from both aquatic and terrestrial cave habitats) have fascinated researchers throughout history. Despite their success in colonizing most marine ecosystems, the adaptations of cave brittle stars (Ophiuroidea) to a stygobiotic lifestyle have been scarcely examined. Employing comparative methods on a data set of two species belonging to the genusOphionereis, this study addresses whether a cave-dwelling species from Cozumel exhibited similar troglomorphic traits as those of other taxa inhabiting caves. Our work demonstrated that some characters representing potential morphological cave adaptations inO. commutabiliswere: bigger sizes, elongation of arms and tube feet and the presence of traits potentially paedomorphic. In addition, an element of ophiuroid’s photoreceptor system, as well as pigmentation, was observed to be peculiar in this stygobiotic species, plausibly as a result of inhabiting a low light-energy environment. Finally, we add evidence to the statement thatO. commutabilisis a cave endemic species, already supported by demography, distribution and origin of this species, and now by a typical array of troglomorphisms.