Erinaceusyllis belizensis (Russell, 1989) n.comb.

Fig. 32A–E

Sphaerosyllis belizensis Russell, 1989: 375, fig. 1; Olano et al., 1998: 86, fig. 2.

Material examined. AUSTRALIA: WESTERN AUSTRALIA. 1 specimen, AM W26803, limestone reef, off Ned’s camp, Cape Range National Park, 21°59'S 113°55'E, sponge with epiphytic algae, and muddy worm tubes, 1.5 m, R.T. Springthorpe, 2 Jan 1984.

Description. Body minute, up to 1.18 mm long, 0.16 mm wide, 20 chaetigers, with scattered small papillae on dorsum and laterally, partially covered by debris. Prostomium oval, wider than long; 4 large eyes in trapezoidal arrangement, nearly in line, and 2 anterior eyespots; antennae spindle- to onion-shaped, with bulbous bases and short to moderately tips; median antenna similar to combined length of prostomium and palps, inserted between eyes, lateral antennae shorter than median antenna, inserted near anterior margin, lateral to eyespots. Palps shorter than prostomium, fused along their length. Peristomium forming a distinct, trilobed hood covering posterior part of prostomium (Fig. 32A); tentacular cirri similar to antennae but much smaller. Dorsal cirri shorter than antennae, longer than tentacular cirri, with bulbous bases and short tips, absent on chaetiger 2 (Fig. 32A), more elongate on midbody. Parapodia conical, with a few papillae. Compound chaetae heterogomph; parapodia each with 1 compound chaeta provided with proportionally long, slender, bidentate blade, about 32 µm, smooth distally, provided with fine, moderately long marginal spines on bases, and 6–7 anteriorly, 4–5 posteriorly, compound chaetae with smooth margin or provided with short, straight spines, unidentate or provided with minute subdistal spine, distally slightly hooked (Fig. 32D), 22–15 µm long. Dorsal simple chaetae from anterior parapodia, unidentate, apparently smooth (Fig. 32C). Ventral simple chaetae slender, smooth, unidentate (Fig. 32E), present on posterior parapodia. Acicula solitary, acuminate (Fig. 32B). Pharynx proportionally slender, through 3 segments; pharyngeal tooth small, located near pharynx opening (Fig. 32A). Proventricle barrel-shaped, through 3 segments, with about 18 muscle cell rows. Pygidium small, with numerous long papillae, anal cirri elongate.

Distribution. Belize, Western and Eastern Mediterranean, Australia (Western Australia).

Habitat. On mangrove roots, on bryozoans, corals, and algae, mud, on shallow water.