Pionosyllis fusigera Augener, 1913

San Martin, G & Hutchings, PA, 2006, Eusyllinae (Polychaeta: Syllidae) from Australia with the Description of a New Genus and Fifteen New Species, Records of the Australian Museum 58, pp. 257-370 : 330

Pionosyllis fusigera Augener, 1913

Fig. 60A–I

Pionosyllis fusigera Augener, 1913: 227 , pl. III Fig. 34, text-fig. 32a–c.

Material examined. Syntype 1 ( HZM V-7951) AUSTRALIA: WESTERN AUSTRALIA: Sharks Bay, Surf Point, Outer Bar , 25°16'S 113°28'E, 1–3.5 m, 16 Jun 1905 .

Description. Specimen in poor condition, covered with crystals of formalin. Body fragile, without colour pattern, but dark, cylindrical, flattened ventrally, convex dorsally, 4 mm long, 0.5 mm wide for 38 chaetigers, incomplete. According to Augener (1913), dorsal cirri, prostomium and palps pigmented brown and anterior segments with brown dorsal bands. Prostomium sub-quadrangular with rounded corners; 4 eyes almost equal in size, arranged in open trapezoidal pattern; 2 nuchal lobes, kidney shaped, located behind posterior pair of eyes ( Fig. 60A). All antennae located on anterior margin of prostomium, short, similar in shape and size, slightly enlarged distally, as long as prostomium; lateral antennae thinner than median one ( Fig. 60A). Palps broad, large, fused basally, widely separated distally, folded ventrally ( Fig. 60B). Peristomial ring shorter than following segments, dorsally covered between first chaetiger and prostomium and visible only laterally and ventrally, with two pairs of tentacular cirri. Dorsal tentacular cirri and some dorsal cirri similar in shape, smooth, thick, club-shaped, basally slender and gradually becoming wider distally, terminating in globular papillae; most anterior cirri slightly shorter than middle and posterior cirri ( Fig. 60B); ventral tentacular cirri similar in shape and size to lateral antennae. Long, club-shaped dorsal cirri alternating with shorter, thinner, digitiform cirri, as long as half of body width ( Fig. 60A). Ventral cirri conical to digitiform, distally pointed, almost as long as parapodia. Parapodia with prechaetal lobe larger than postchaetal one ( Fig. 60C,D). Compound chaetae heterogomph falcigers; shafts with distal short spines; blade tips bidentate, distal tooth hooked, proximal tooth similar in size to distal one ( Fig. 60E,H,I). About 12 compound chaetae on anterior parapodium, number progressively decreasing posteriorly; dorsalmost compound chaetae on each parapodium with elongate, slender, minutely bidentate blade, with numerous fine, short spines on edge, 60 µm in length on anterior parapodia, shorter, about 36 µm in length, posteriorly. Blades of remaining chaetae more strongly bidentate, all similar in shape with slight dorsoventral and anteroposterior gradation in size, blades progressively becoming shorter and wider posteriorly, about 54 µm in length dorsally and 28 µm in length ventrally on anterior parapodia; blades on posterior parapodia about 31 µm in length dorsally and 20 µm in length ventrally ( Fig. 60H,I). Anterior parapodia with 2 straight, thick, acuminate, distally pointed aciculae; posterior parapodia with single acicula ( Fig. 60F,G). Pharynx, removed from specimen, reaching segment 4, pharyngeal tooth on segment 2 (fide Augener, 1913). Proventricle barrel shaped, extending through 3 chaetigers (from 4 to 7) ( Fig. 60A) with about 18 muscle cell rows.

Habitat. Occurring in depths of 1 to 3.5m.

Distribution. Australia (Western Australia).