Revision of Sternaspis Otto, 1821 (Polychaeta, Sternaspidae)

• Published in: ZooKeys
• Main Authors: Sendall, Kelly, Salazar-Vallejo, Sergio
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2013
• Subjects: Widespread species; taxonomy; systematic; Annelida; Echiurida; ventro-caudal shield; Malmgren; New Zealand; Pacific; Iceland
• Online Access: https://zenodo.org/record/578335; https://doi.org/10.3897/zookeys.286.4438

Sternaspid polychaetes are common and often abundant in soft bottoms in the world oceans. Some authors suggest that only one species should be recognized, whereas others regard a few species as widely distributed in many seas and variable depths from the low intertidal to about 4400 m. There are some problems with species delineation and the distinctive ventro-caudal shield has been disregarded or barely used for identifying species. In order to clarify these issues, the ventral shield is evaluated in specimens from the same locality and its diagnostic potential is confirmed. On this basis, a revision of Sternaspis Otto, 1821 (Polychaeta: Sternaspidae) is presented based upon type materials, or material collected from type localities. The sternaspid body, introvert hooks and shield show three distinct patterns, two genera have seven abdominal segments and tapered introvert hooks, and one genus has eight abdominal segments and spatulate introvert hooks. The ventro-caudal shield has three different patterns: stiff with ribs, and sometimes concentric lines, stiff with feebly-defined ribs but no concentric lines, and soft with firmly adhered sediment particles. Sternaspis is restricted to include species with seven abdominal segments, falcate introvert hooks, and stiff shields, often exhibiting radial ribs, concentric lines or both. Sternaspis includes, besides the type species, S. thalassemoides Otto, 1821 from the Mediterranean Sea, S. affinis Stimpson, 1864 from the Northeastern Pacific, S. africana Augener, 1918, stat. n. from Western Africa, S. andamanensis sp. n. from the Andaman Sea, S. costata von Marenzeller, 1879 from Japan, S. fossor Stimpson, 1853 from the Northwestern Atlantic, S. islandica Malmgren, 1867 from Iceland, S. maior Chamberlin, 1919 from the Gulf of California, S. princeps Selenka, 1885 from New Zealand, S. rietschi Caullery, 1944 from abyssal depths around Indonesia, S. scutata (Ranzani, 1817) from the Mediterranean Sea, S. spinosa Sluiter, 1882 from Indonesia, and S. thorsoni sp. n. from ...