''Hermadion'' is a genus of marine

polychaete Polychaeta () is a paraphyletic class of generally marine Annelid, annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called c ...

worms belonging to the family

Polynoidae Polynoidae is a family (biology), family of marine Polychaete worms known as "scale worms" due to the scale-like elytron (Annelida), elytra on the dorsal surface. Almost 900 species are currently recognised belonging to 9 subfamilies and 167 gen ...

, the scaleworms. ''Hermadion'' contains a single species, ''Hermadion magalhaensi'' which is known from the South

Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...

, South

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

and southern

Indian Indian or Indians may refer to: Associated with India * of or related to India ** Indian people ** Indian diaspora ** Languages of India ** Indian English, a dialect of the English language ** Indian cuisine Associated with indigenous peoples o ...

Oceans at depths to about 110 m.Kinberg, J.G.H. (1856). Nya slägten och arter af Annelider, Öfversigt af Kongl. Vetenskaps-Akademiens Förhhandlingar Stockholm, 12 (9-10), 381-388 ead 1855; printed 1856, available online at https://www.biodiversitylibrary.org/page/15970133Barnich, R.; Fiege, D.; Micaletto, G.; Gambi, M. C. (2006). Redescription of ''Harmothoe spinosa'' Kinberg, 1856 (Polychaeta: Polynoidae) and related species from Subantarctic and Antarctic waters, with the erection of a new genus. Journal of Natural History. 40(1-2): 33-75., available online at https://doi.org/10.1080/00222930500445044

Description

''Hermadion magalhaensi'' is a short-bodied scale worm with fewer than 50 segments and 15 pairs of

elytra An elytron (; ; : elytra, ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometime ...

. The elytra are large but leave a small median part of the body uncovered. The

prostomium The prostomium (From Ancient Greek, meaning "before the mouth"; : prostomia; sometimes also called the "acron") is the Cephalization, cephalized first body segment in an annelid worm's body at the anterior end. It is in front of (but does not in ...

is bilobed and rounded anteriorly, lacking acute cephalic peaks. The antennal styles have slender papillae and the lateral antennae are inserted ventrally, beneath the median antenna. The neuropodial lobe is elongate and tapering to a narrow tip. The

notochaetae A chaeta or cheta (; ) is a chitinous bristle or seta found on annelid worms, although the term is also frequently used to describe similar structures in other invertebrates such as arthropods. Polychaete annelids (''polychaeta'' literally mean ...

have pointed tips and are distinctly thicker than the

neurochaetae A chaeta or cheta (; ) is a chitinous bristle or seta found on annelid worms, although the term is also frequently used to describe similar structures in other invertebrates such as arthropods. Polychaete annelids (''polychaeta'' literally mean ...

. The neurochaetae are simple and none have bidentate tips.Bock, Gordon, Fiege, Dieter & Barnich, Ruth 2010. Revision of ''Hermadion'' Kinberg, 1856, with a redescription of ''Hermadion magalhaensi'' Kinberg, 1856, Adyte hyalina (G.O. Sars, 1873) n. comb. and Neopolynoe acanellae (Verrill, 1881) n. comb. (Polychaeta:Polynoidae). Zootaxa, 2554, 45–61, available online at http://www.mapress.com/zootaxa/list/2010/2554.html

References

{{Taxonbar, from1=Q3916435, from2=Q2627327 Phyllodocida Monotypic annelid genera Polychaete genera