Polycirrus plumosus

Polycirrus plumosus (Wollebaek, 1912)

Fig. 51a–d

Ereutho plumosa Wollebaek, 1912: 82–83, figs 1–4.

Type locality. Norway.

Material examined. None.

Description. Body long, anterior and mid- body usually thick, about 100 segments (no dimensions provided). Body colouration when preserved whitish.

Venter anteriorly with mid-ventral groove and poorly defined ventro-lateral pads (about 9 unpaired narrow ventral pads, followed by 4–5 paired ones); pads papillose, incised. Mid-ventral groove from segment 3 (Fig. 51a).

Buccal tentacles two types: (1) cylindrical, thickened distally and distinctly grooved and (2) cylindrical, uniformly thin and weakly grooved. Upper lip comprising medial broad lobe only. Outer lower lip subconical lobe protruding above venter, long, prominent (Fig. 51a).

Notochaetigerous segments 17–19, extending to segments 19–21. Notopodia more-or-less rectangular, prechaetal lobe low, postchaetal lobe digitiform, longer than prechaetal. Notochaetae within a chaetiger two types: primary type smooth, narrowly winged, subdistally slightly expanded, posteriorly same form as those anteriorly (Fig. 51b); secondary notochaetae in all chaetigers pinnate (Fig. 51c). Neurochaetae beginning on segment 18–20. Uncini with short neck and straight to convex base (Type 1), teeth above main fang arranged in double transverse series (formula not deducible), subrostral process present as low, rounded protuberance (Fig. 51d).

Nephridial papillae present. Pre-gular membrane nephridial papillae present on segments 3–4. Post-gular membrane nephridial papillae present, extending from segment 5 to 9.

Comments. The above description is scored primarily from Holthe (1986b), which appears to be based on material collected in the Faroes, the eastern North Sea, the west coast of Sweden, and western Norway near the type locality. The one exception is that the ventrolateral pads are illustrated by Wollebaek (1912) as being slightly papillose (Fig. 48a), whereas this detail is missing in Holthe’s illustration. According to Holthe (1986b) the type should be in the Zoological Museum, Oslo; however, our correspondance with this institution indicates that they have failed to locate the types. Wollebaek provides sufficient character information for the species to be accepted as valid.