Polycirrus nervosus Marenzeller, 1884

Glasby, Christopher J. & Hutchings, Pat, 2014, Revision of the taxonomy of Polycirrus Grube, 1850 (Annelida: Terebellida: Polycirridae), Zootaxa 3877 (1), pp. 1-117 : 81

Polycirrus nervosus Marenzeller, 1884

Fig. 43a–h

Polycirrus nervosus Marenzeller, 1884: 209–210 , pl. 2 fig. 7.

Type locality. Japan .

Material examined. SYNTYPES: NMW 1794 . Japan, Musei Vindobonensis Evertebr. varia coll. Drasch , 1877.

Description. Syntypes well preserved with body wall intact and chaetae mainly intact, pale yellow in colour. Syntypes consist of one complete individual 20 mm long, 2 mm wide excluding buccal tentacles, with about 90 segments, and one anterior fragment 3 mm long, 1.5 mm wide for about 11 segments. Description based upon complete syntype. Sex unknown.

Dorsum anteriorly faintly tessellated. Venter anteriorly with mid-ventral groove and discrete ventro-lateral pads; pads incised and tessellated, extending from segment 3 to 11. Mid-ventral groove from segment 4 ( Fig. 43a ).

Buccal tentacles of three types, numerous although mostly detached: (1) cylindrical, thickened distally and distinctly grooved, (2) cylindrical, uniformly thin and weakly grooved, and (3) leaf-shaped ones also possibly present, all arising at junction between prostomium and upper lip. Prostomial ridge distinctly curved, extending laterally along anterodorsal base of upper lip. Upper lip with prominent medial lobe, small wing-like lateral lobes, margin of medial lobe convoluted; oral surface glandular and ciliated. Inner lower lip oblong, ridged; outer region flat, shield-like, inverted T-shaped, ridged and grooved, extending posteriorly to segment 3. Achaetous segments visible dorsally but obscured by expanded outer lower lip ventrally.

Notochaetigerous segments 42, extending approximately to segment 44. Notopodia more-or-less rectangular, prechaetal lobe low, postchaetal lobe digitiform, slightly longer than prechaetal ( Fig. 43b ). Notochaetae within a chaetiger consisting of one type (chaetigers 2, 26 examined), gradually elongating from dorsal to ventral, hirsute, uniformly tapered, posteriorly same form as those anteriorly ( Fig. 43c–e ). Neurochaetae beginning on segment 15. Neuropodial tori ridge-like, differ along body, becoming more erect posteriorly. Uncini with short neck and straight to convex base (Type 1), teeth above main fang arranged in one or two transverse series (MF:3–7 or MF:3–5:3–5) enlarged median tooth above main fang absent, subrostral process present as low protuberance sharp or rounded ( Fig. 43f–h ).

Nephridial papillae present, small, spherical. Pre-gular membrane nephridial papillae present on segments 3–4. Post-gular membrane nephridial papillae present, extending from segment 5 to 10 (at least, anterior body wall damaged); situated at ventral base of notopodia. Pygidium simple rosette.

Figures

FIGURE 43. Polycirrus nervosus Marenzeller. Syntypes NMV 1794.a. Anterior ventral view. b. Right side anterior lateral view of notopodium, chaetiger 2. c. Notochaetae from chaetiger 2 illustrated at x40 and x100. d. Notochaeta from chaetiger 12 illustrated at x40 and x100. e. Notochaeta from chaetiger 2. f. Lateral view of uncinus from segment 15. g. Lateral and frontal views of uncini from segment 28. h. Lateral and frontal views of uncinus from mid-posterior body chaetiger.