Polycirrus arenivorus Caullery, 1915

Glasby, Christopher J. & Hutchings, Pat, 2014, Revision of the taxonomy of Polycirrus Grube, 1850 (Annelida: Terebellida: Polycirridae), Zootaxa 3877 (1), pp. 1-117 : 24

Polycirrus arenivorus Caullery, 1915

Fig. 8a–e

Polycirrus (Leucariste) arenivorus Caullery, 1915: 244–248 , fig.1–2.

Type locality. Anse , France .

Material examined. HOLOTYPE?: MNHN 1546 , France, Anse , St. Martin, 49˚43′ N, 1˚55′30′′ W, sand, intertidal, coll. ix.1898. (Type status is questionable as this specimen was not included in the list of types held at the MNHN by Solís-Weiss et al. (2004)).

Description. Holotype well preserved with body wall intact and chaetae mainly intact, pale cream in colour, in two fragments, anterior fragment 5 mm long and 1.2 mm wide for 10 segments excluding buccal tentacles, another fragment 20 mm long and 1.2 mm wide with about 85 segments. Two fragments possibly previously connected forming an entire animal. Sex unknown.

Dorsum anteriorly tessellated becoming less so posteriorly. Venter anteriorly with mid-ventral groove from segment 3 ( Fig. 8a ) and discrete ventro-lateral pads from segment 2 to 18 (decreasing in size posteriorly); pads incised by transverse grooves.

Buccal tentacles detached, numerous, of two types: (1) cylindrical, thickened distally, distinctly grooved and (2) cylindrical, uniformly thin, weakly grooved; both types arising dorsally on prostomial ridge. Prostomial ridge slightly curved, extending laterally. Upper lip trefoiled with lateral, blindly ending, enclosed diverticulae; margin of medial lobe straight; oral surface glandular and ciliated. Inner lower lip oblong (hidden by upper lip), tessellated; outer region flat, shield-like, oblong, longer than wide, ridged and strongly grooved, extending posteriorly to segment 3 ( Fig. 8a ). Achaetous segments not visible.

Notochaetigerous segments 29, extending to segment 31. Notopodia more-or-less rectangular and tapered distally, prechaetal lobe low, postchaetal lobe digitiform, postchaetal lobe longer than prechaetal ( Fig. 8b ). Notochaetae all of one type (chaetigers 2, 19 examined), two distinct lengths, hirsute, uniformly tapered, posteriorly same form as those anteriorly ( Fig. 8c ). Neurochaetae beginning on segment 12. Neuropodial tori ridge like, similar along body. Uncini with short neck and straight to convex base (Type 1), teeth above main fang arranged in double transverse series ( MF:3:5) enlarged median tooth above main fang absent, subrostral process absent ( Fig. 8d, e ) .

Nephridial papillae present, globular, flattened. Pre-gular membrane nephridial papillae absent. Post-gular membrane nephridial papillae present, extending from segments 5–8; situated at base of notopodia. Pygidium simple rosette.

Comments. We assume that the specimen examined here is the holotype, but there is some uncertainty over its status as Caullery (1915) had previously indicated that he did not believe in depositing type material. The specimen examined is from the type locality specified by Caullery (1915) and it resembles the original description.

Figures

FIGURE 8. Polycirrus arenivorus Caullery. Holotype MHNS 1546. a. Anterior ventral view. b. Left side posterior lateral view of notopodium, chaetiger 2. c. Notochaetae from chaetiger 2 illustrated at x40 and x100. d. Lateral and frontal views of uncini from chaetiger 20. e. Lateral view of uncinus from posterior chaetiger.