Blog
About

0
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

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

      , ,

      Subterranean Biology

      Pensoft Publishers

      Read this article at

      ScienceOpenPublisher
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          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 genus Ophionereis, 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 in O. commutabilis were: 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 that O. commutabilis is a cave endemic species, already supported by demography, distribution and origin of this species, and now by a typical array of troglomorphisms.

          Related collections

          Most cited references 49

          • Record: found
          • Abstract: found
          • Article: not found

          Calcitic microlenses as part of the photoreceptor system in brittlestars.

          Photosensitivity in most echinoderms has been attributed to 'diffuse' dermal receptors. Here we report that certain single calcite crystals used by brittlestars for skeletal construction are also a component of specialized photosensory organs, conceivably with the function of a compound eye. The analysis of arm ossicles in Ophiocoma showed that in light-sensitive species, the periphery of the labyrinthic calcitic skeleton extends into a regular array of spherical microstructures that have a characteristic double-lens design. These structures are absent in light-indifferent species. Photolithographic experiments in which a photoresist film was illuminated through the lens array showed selective exposure of the photoresist under the lens centres. These results provide experimental evidence that the microlenses are optical elements that guide and focus the light inside the tissue. The estimated focal distance (4-7 micrometer below the lenses) coincides with the location of nerve bundles-the presumed primary photoreceptors. The lens array is designed to minimize spherical aberration and birefringence and to detect light from a particular direction. The optical performance is further optimized by phototropic chromatophores that regulate the dose of illumination reaching the receptors. These structures represent an example of a multifunctional biomaterial that fulfills both mechanical and optical functions.
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            The cave environment.

             Carl White,  T Poulson (1969)
              Bookmark
              • Record: found
              • Abstract: not found
              • Book: not found

              Cave Life

                Bookmark

                Author and article information

                Journal
                Subterranean Biology
                SB
                Pensoft Publishers
                1314-2615
                1768-1448
                March 05 2020
                March 05 2020
                : 33
                : 87-108
                Article
                10.3897/subtbiol.33.48721
                © 2020

                http://creativecommons.org/licenses/by/4.0/

                Comments

                Comment on this article