Hesione helenensis Salazar-Vallejo 2018, n. sp.

• Main Author: Salazar-Vallejo, Sergio I.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2018
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Phyllodocida; Hesionidae; Hesione; Hesione helenensis; South Atlantic Ocean; James Bay
• Online Access: https://doi.org/10.5281/zenodo.3810264; http://treatment.plazi.org/id/C17687BDFFFFFFD7FC3EFAB6DBEFFD5B

Hesione helenensis n. sp. (Fig. 20) urn:lsid:zoobank.org:act: F44B445E-71C8-493B-B59F-2B193435A522 TYPE MATERIAL. — South Atlantic Ocean. Holotype, USNM 33148, and one paratype, USNM 1479052, Saint Helena Island, James Bay, IV.1964, A. Loveridge coll. [paratype 39 mm long, 4 mm wide; slightly distorted; anterior end compressed; dorsal cirrostyles swollen basally, multiarticulated; chaetal lobes markedly contracted, invaginated into neuropodia; acicular lobes barely seen, rounded, upper tine 3-4 times longer than lower one; ventral cirri basally swollen, longer than neuropodia, slightly articulated; posterior end truncate; anus with about 6 anal papillae]. ETYMOLOGY. — The species name is an adjective derived from Saint Helena island, and as in some other similar names, the last vowel in the proper name is suppressed, and the suffix - ensis is added to indicate its current distribution. DISTRIBUTION. — Only known from Saint Helena island, in subtidal rocky bottoms. DIAGNOSIS. — Hesione with prostomium slightly curved laterally; parapodia with dorsal cirri basally swollen, dorsal cirrophore twice as long as wide; larger acicula blackish; acicular lobe single, short, massive, blunt, upper tine 3 times longer than lower one; neurochaetal blades bidentate, 4-6 times as long as wide; subdistal tooth smaller; guards approaching distal tooth. DESCRIPTION Holotype, USNM 33148, complete, subcylindrical, tapered posteriorly, without pigmentation (Fig. 20A) in ethanol; most cirri and many neurochaetal blades broken; left parapodium of chaetiger 9 removed (kept in vial). Body 39 mm long, 4 mm wide. Prostomium slightly as wide as long, anterior margin projected anteriorly, lateral margins rounded, posterior margin with a shallow cleft, about 1/5 as long as prostomial length, longitudinal depression slight (Fig. 20B). Antennae minute, left one visible, fusiform, 2-3 times as long as wide, about as long as interocular distance. Eyes brownish, anterior ones larger and more separated than posterior ones. Tentacular cirri long, ...