''Parahololepidella'' is a genus of marine

annelids The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ...

in 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). The genus contains a single species, ''Parahololepidella greeffi'', This species is known from the east equatorial

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

and

Cape Verde Islands Cape Verde or Cabo Verde, officially the Republic of Cabo Verde, is an island country and archipelagic state of West Africa in the central Atlantic Ocean, consisting of ten volcanic islands with a combined land area of about . These islands ...

at a maximum depth of 30m.Pettibone, Marian H. (1969). The genera Polyeunoa McIntosh, Hololepidella Willey, and three new genera (Polychaeta, Polynoidae). Proceedings of the Biological Society of Washington. 82: 43-62., available online at http://biodiversitylibrary.org/page/34595050

Description

Species of ''Parahololepidella'' are long-bodied, with 130 or more segments and 60 or more 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 ...

, which continue to the end of the body. The elytra are smooth and very small, leaving most of the parapodia and dorsum uncovered. 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 ...

have a sub-acicular process, and 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 ...

are more slender than

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 ...

, none of which are bidentate. Cephalic peaks are also present on 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 ...

Description of ''Parahololepidella greeffi''

Specifically, ''P. greeffi'' has 136 segments and 67 pairs of

. The dorsum is a greyish-yellow with a median purple band and there are dark spots near the base of the

parapodia 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 ...

. The lateral antennae are inserted ventrally (beneath the

and median antenna), and the

are thinner than the

. Bidentate neurochaetae are also absent.Britayev TA, Gil J, Altuna Á, Calvo M, Martín D (2014) New symbiotic associations involving polynoids (Polychaeta, Polynoidae) from Atlantic waters, with redescriptions of Parahololepidella greeffi (Augener, 1918) and Gorgoniapolynoe caeciliae (Fauvel, 1913). Memoirs of Museum Victoria 71: 27–43. https://doi.org/10.24199/j.mmv.2014.71.04.

Taxonomic comments

''Parahololepidella'' is distinguished from other scale worms by the subacicular neuropodial process and having numerous (50–60 or more pairs) of very small elytra which only cover the base of the parapodium.

Biology and Ecology

''P. greeffi'' is a

commensal Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit f ...

organism. Its host are antipatharian corals in the genus '' Tanacetipathes''.

References

{{Taxonbar, from=Q61609157 Phyllodocida