Erinaceusyllis cirripapillata, Guillermo San Martin, 2005

Guillermo San Martin, 2005, Exogoninae (Polychaeta: Syllidae) from Australia With the Description of a New Genus and Twenty-two New Species, Records of the Australian Museum 57, pp. 39-152 : 81

Erinaceusyllis cirripapillata n.sp.

Fig. 36A–H

Material examined. AUSTRALIA: NEW SOUTH WALES. HOLOTYPE: AM W26711, North Creek Canal, Richmond River, 28°52.1'S 153°32.8'E, mud, 3 m, P.B. Berents, S.J. Keable & A. Murray, 02 Mar 1992, NSW 627.

Description. Body small, 2.5 mm long, 0.18 mm wide, 31 chaetigers, provided with small, scattered papillae on dorsum, more abundant on lateral margins of segments (Fig. 36A). Prostomium rectangular, wider than long; 4 large eyes in line, near to posterior margin of prostomium, and 2 anterior eyespots; median antenna longer than combined length of prostomium and palps, inserted between eyes, lateral antennae shorter than median antenna, inserted near anterior margin, slightly posterior and lateral to eyespots. Palps shorter than prostomium, fused along their length, distally notched, provided with few, small papillae. Peristomium shorter than following segments, covering dorsally posterior margin of prostomium, bilobed (Fig. 36A); tentacular cirri similar to antennae but smaller. Dorsal cirri shorter than antennae, longer than tentacular cirri, with bulbous bases and short tips, absent on chaetiger 2, more elongate posteriorly (Fig. 36A,B); antennae, tentacular cirri and dorsal cirri provided with numerous small papillae and 1, sometimes 2, long, distinct papillae, mushroom-shaped, with a stalk and distally enlarged and truncated (Fig. 36A,B). Parapodia rectangular to conical, with scattered papillae, sometimes similar to those of dorsal cirri. Compound chaetae heterogomph, smooth on margin or provided with short, straight spines on longer blades; blades elongate, unidentate, distally slightly hooked (Fig. 36D,F); anterior parapodia each with 6–7 compound chaetae with dorsoventral gradation in length, 28–12 µm, 6 on posterior parapodia, similar to those of anterior parapodia but slender. Dorsal simple chaetae from chaetiger 7, unidentate, provided with short marginal spines (Fig. 36E). Ventral simple chaetae slender, smooth, unidentate (Fig. 36G), present on posterior parapodia. Acicula solitary, acuminate (Fig. 36H). Pharynx proportionally slender, through 3 segments; pharyngeal tooth on pharynx opening (Fig. 36A). Proventricle long and wide, barrel-shaped, through 3 segments, with about 26 muscle cell rows. Pygidium small, with numerous papillae, anal cirri missing.

Remarks. Erinaceusyllis cirripapillata n.sp., is characterized by having papillae on dorsal cirri, one of them being distinctive, mushroom-shaped. None species of this genus or Sphaerosyllis is described having that kind of papillae on dorsal cirri.

Distribution. Australia (New South Wales).

Habitat. Mud in shallow water.

Etymology. The name of the species refers to the distinct, characteristic papillae on the dorsal cirri.