''Harmothoe'' 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 ...

'' (scale worms). Species of ''Harmothoe'' are found world-wide to depths of at least 5,000 m but are more common in shallower water.

Description

Body dorsoventrally flattened, short, with 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 ...

and up to 50 segments; the body is more or less covered by elytra, although long specimens may have a short posterior region 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 rounded anteriorly and has distinct cephalic peaks on the dorsal surface. There are three antennae, a pair of lateral antennae inserted ventrally, directly beneath the median antenna ceratophore. The

neuropodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; : parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed late ...

are elongate and tapering. The notoochaetae are stout with transverse rows of spines and blunt tips. 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 ...

also have transverse rows of spines and both unindentate and bidentate neurochaetae are present.Barnich R, Fiege D (2000) Revision of the Mediterranean species of Harmothoe Kinberg, 1856 and Lagisca Malmgren, 1865 Polychaeta: Polynoidae: Polynoinae) with descriptions of a new genus and a new species. Journal of Natural History 34: 1889–1938. https://doi.org/10.1080/00222930050144783

Biology

''Harmothoe'' is one of many genera in the family Polynoidae that contain bioluminescent species.

Taxonomic comments

In many parts of the world, identification of species in this diverse genus is problematic, however recently published revisions provide a guides to species of ''Harmothoe'' from the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

, Northeast AtlanticBarnich R, Fiege D (2000) Barnich R, Fiege D (2009) Revision of the genus Harmothoe Kinberg, 1856 (Polychaeta: Polynoidae) in the Northeast Atlantic. Zootaxa 2104: 1–76. https://doi.org/10.11646/zootaxa.2104.1.1 and from the

Subantarctic The sub-Antarctic zone is a physiographic region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46th parallel south, 46° and 60th parallel south, 60° south of t ...

and

Antarctic The Antarctic (, ; commonly ) is the polar regions of Earth, polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is antipodes, diametrically opposite of the Arctic region around the North Pole. The Antar ...

.Barnich R, Fiege D, Micaletto G, Gambi MC (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: 33–75. https://doi.org/10.1080/00222930500445044

Species

The genus ''Harmothoe'' includes 152 species as of June 2020

References

Polychaete genera Phyllodocida Bioluminescent annelids {{annelid-stub