Polycirrus nephrosus Hutchings & Glasby, 1986

Glasby, Christopher J. & Hutchings, Pat, 2014, Revision of the taxonomy of Polycirrus Grube, 1850 (Annelida: Terebellida: Polycirridae), Zootaxa 3877 (1), pp. 1-117 : 78

Polycirrus nephrosus Hutchings & Glasby, 1986

Fig. 42a–f , Table 1

Polycirrus nephrosus Hutchings & Glasby, 1986: 338–339 , figs 8a–e, 12E.

Type locality. Port Hacking , Sydney, NSW, Australia .

Material examined. HOLOTYPE: AM W199641 , Australia, New South Wales, Port Hacking, Ship Rock , 34˚04′ S, 151˚06′ E.

Description. Holotype 27 mm long, 1.2 mm wide with 37 segments.

Dorsum anteriorly tessellated and annulated, dorsal annulations may extend ventrally. Venter anteriorly with mid-ventral groove and poorly defined, slightly inflated, ventro-lateral pads, more-or-less smooth. Mid-ventral groove from segment 3.

Buccal tentacles of two types although few tentacles remaining: (1) cylindrical, thickened distally and distinctly grooved and (2) cylindrical, uniformly thin and weakly grooved, both arising at junction between prostomium and upper lip. Prostomial ridge slightly curved, extending laterally along anterodorsal base of upper lip. Upper lip trefoiled with lateral blindly-ending enclosed diverticulae, margin of medial lobe convoluted; oral surface glandular and ciliated. Inner lower lip subtriangular (narrow), smooth; outer region subconical lobe protruding above venter (recurved posteriorly in some specimens), smooth. Achaetous segments not visible ( Fig. 42a ).

Notochaetigerous segments 18, extending to segment 20. Notopodia digitiform, rapidly decreasing in size posteriorly, lobes both similar, low and rounded, sometimes upturned, making notopodium appear knob-tipped ( Fig. 42b ). Notochaetae within a chaetiger consisting of one type, gradually elongating from dorsal to ventral, pinnate, uniformly tapered, posteriorly same form as those anteriorly ( Fig. 42c, d ). Neurochaetae beginning on segment 14. Neuropodial tori erect pinnules, differ along body, initially papilliform, then increasing in size slightly posteriorly. Uncini with short neck and straight to convex base (Type 1), although uncini have a main fang and crest similar to the elongate Type 2, teeth above main fang arranged in single transverse series ( MF:3–7), enlarged median tooth above main fang present, subrostral process absent ( Fig. 42e, f ) .

Nephridial papillae present, spherical. Pre-gular membrane nephridial papillae present on segments 3, 4. Postgular membrane nephridial papillae present, extending from segment 5 to 15; situated at anterior base of notopodia. Pygidium papillated ring.

Comments. Hutchings & Glasby (1986) report the following variation in the paratypes: 14–26 notochaetigerous segments, neurochaetae from segment 12–16 ( Table 1 ). The notochaetae are described by them as being hirsute, but the closeup figure in the original description (fig. 8d) clearly indicates that they are pinnate.

Figures

FIGURE 42. Polycirrus nephrosus Hutchings & Glasby. a. Ventral view of head end. b. Posterior view of notopodium, chaetiger 3. c, d. Notochaeta from notopodium, chaetiger 2. e. Lateral view of mid-posterior body uncinus. f. Frontal views from same. Scales c=0.03 mm, d, e=0.01 mm, b, f=0.1 mm, a=1 mm. (Reproduced with permission from Hutchings & Glasby, 1986; http://www.australianmuseum.net.au/Uploads/Journals/17666/185_complete.pdf).