Tardígrados del Parque Natural Fragas do Eume (Galicia, NO España) con la primera cita de Echiniscus bigranulatus Richters, 1907 (Tardigrada, Heterotardigrada) en la península Ibérica

Abstract

Tardigrades are protostome invertebrate animals currently located in the clade Panarthropoda, related to Arthropods and Onichoforans. Despite their almost ubiquitous nature, as they can be found in both terrestrial and aquatic habitats (marine and continental), their microscopic size makes them often go unnoticed. There are very few studies regarding this phylum in Galicia, all focused on marine species. In order to at least partially overcome this lack of information, a sampling of a variety of terrestrial habitats was carried out (mosses, lichens, ferns, leaf litter, liverworts and fungi), in Fragas do Eume Natural Park (Galicia, NW Iberian Peninsula), as well as marine (intertidal sand) at a nearby beach, A Madalena, in the ria Ares-Betanzos. The eight identified species were typical of limnoterrestrial environments and, with the exception of individuals of genus Macrobiotus, constitute new record for Galicia. The species are: Macrobiotus furcatus Ehrenberg, 1859; Minibiotus intermedius (Plate, 1889); Tenuibiotus hystricogenitus (Maucci, 1978); Astatumen trinacriae (Arcidiacono, 1962); Echiniscus bigranulatus Richters, 1907; Hypsibius convergens (Urbanowicz, 1925) and one unnamed species belonging to the group H. pallidus Thulin, 1911 – H. microps Thulin, 1928. In this article, the species Echiniscus bigranulatus Richters, 1907 is recorded for the first time in the Iberian Peninsula. Three specimens of this heterotardigrade species were found on the fronds of the pteridophyte Blechnum spicant (L.) Roth, and among the main characters taken into account for their identification stand out the presence and distribution of the cuticular pores (design bigranulatus), echiniscus type claws, as well as the presence of various cuticular plates and appendages (cirri). As a consequence of this study the Galician diversity of tardigrades has been increased 70%.