Kinorhynchs are tiny (generally less than 1 mm) worm like Animals largely found in marine sediments, for which reason they are sometimes known as 'Mud Dragons'. They appear to be ubiquitous members of the interstitial meiofauna (Animals that live between sediment grains) in shallow marine habitats, but have been studied in relatively few locations. However, not all Kinorhynchs are sediment-dwellers, with members of the group having been found living on a wide range of Algae, marine Plants, and Animals.
In a paper published in The Eutopean Zoological Journal on 3 February 2024, Adele Cocozza di Montanara of the Department of Science and Technology at the Parthenope University of Naples, Alberto González-Casurrubios of the Department of Biodiversity, Ecology and Evolution at the Complutense University of Madrid, and Diego Cepeda of the Centre for Research on Biodiversity and Global Change at the Autonomous University of Madrid, and the Department of Life Sciences at Alcalá University, describe a new species of Kinorhynch from a macerating Neptune Grass environment off the coast of Ischia Island in the western Mediterranean Sea.
Neptune Grass, Posidonia oceanica, is a form of Seagrass endemic to the Mediterranean, where it forms vast meadows in the photic parts of the sea (i.e. those areas where sufficient sunlight penetrates to allow photosynthesis). Seagrasses are important habitat-forming organisms, and a wide range of Animals, including Kinorhynchs are adapted to life in these meadows. However, as well as meadows, Seagrasses also form areas called 'macerating Seagrass detrital bottoms', where large volumes of decomposing leaves and rhizomes accumulate, typically below the photic zone, forming an important marine carbon sink. Whilst these environments have been known since the 1950s, very little attention has been paid to them or the fauna which live there, to which end Cocozza di Montanara et al. have begun a project to study the fauna of the macerating Seagrass detrital bottom environment of the Regno di Nettuno Marine Protected Area, along the coast of Ischia Island off the western coast of Italy.
The new species is placed in the genus Echinoderes, and given the specific name semprucciae, in honour of Federica Semprucci of the University of Urbino Carlo Bo, for acting as co-supervisor for Adele Cocozza di Montanara's PhD and supporting and guiding her research on meiofauna. The species is described from two specimens, both collected on 19 June 2020 near Ischia Island, an adult female, collected at a depth of 80 m, and an adult male collected at a depth of 70 m.
The two known specimens of Echinoderes semprucciae are 202 μm (female) and 193 μm (male) in length, with a retractable mouth cone surrounded by oral styles. This retractable mouth is mounted on an organ called the introvert, which has six concentric rings of scalids and 10 longitudinal sectors defined by the arrangement of primary spinoscalids. Behind the head is a neck section, then a trunk comprising eleven segments, with spines on segments four, six, eight, nine, and eleven; the two spines on segment eleven being elongated to form a pair of tail-like structures.
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