Erinaceusyllis ettiennei n.sp.

Fig. 35A–F

Material examined. AUSTRALIA: QUEENSLAND. HOLOTYPE: AM W26624, Halifax Bay, north of Townsville, 19°10'S 146°44'E, 5 m, Queensland Nickel Pty Ltd, July 1977. PARATYPES: 3 specimens, AM W26625, Halifax Bay, north of Townsville, 19°10'S 146°44'E, 5 m, Queensland Nickel Pty Ltd, July 1977. Several fragments on SEM stub, AM W26936, Hinchinbrook Channel, 18°20'S 146°4'E, tidal flats (mud & sand), S. Dittmann, 20 Oct 1991. 1 specimen, AM W26937, Hinchinbrook Channel, 18°20'S 146°4'E, tidal flats (mud & sand), S. Dittmann, 14 Oct 1989. several fragments on SEM stub, AM W26938, Hinchinbrook Channel, 18°20'S 146°4'E, tidal flats (mud & sand), S. Dittmann, 20 Nov 1988. 1 specimen, AM W26939, Hinchinbrook Channel, 18°20'S 146°4'E, tidal flats (mud & sand), S. Dittmann, 20 Nov 1988. 1 specimen, AM W27668, Hinchinbrook Channel, 18°20'S 146°4'E, tidal flats (mud & sand), S. Dittmann, 22 Oct 1991.

Description. Body small to minute, 1.2 mm long, 0.15 mm wide, 19–22 chaetigers, covered with small, scattered, indistinct papillae. Prostomium oval, wider than long; 4 large eyes in trapezoidal arrangement, nearly in line, and 2 anterior eyespots; antennae with bulbous bases and with short tips; median antenna similar to combined length of prostomium and palps, inserted slightly in front to anterior eyes; lateral antennae shorter than median antenna, inserted on anterior margin, near eyespots. Palps similar in length to prostomium, fused along their length, but with a distinct distal notch. Peristomium similar to following segments, covering dorsally posterior margin of prostomium, slightly bilobed (Fig. 35A); 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 (Fig. 35A). Compound chaetae heterogomph, similar throughout; blades slender, elongate, unidentate, distally slightly hooked, margin provided with short, thin spines on longer blades (Fig. 35C); parapodia each with 2 compound chaetae with long, spiniger-like blade, about 53–48 µm on midbody, and other 6 provided with filiform, curved, sabre-shaped blades, with normal dorsoventral gradation, 30–13 µm long. Dorsal simple chaetae from midbody, unidentate, smooth (Fig. 35D). Ventral simple chaetae slender, smooth, unidentate (Fig. 35F), present on posterior parapodia.Acicula solitary, acuminate (Fig. 35E), with minute subdistal spines. Pharynx proportionally long and slender, through 4 segments; pharyngeal tooth small, located near opening (Fig. 35A), pharynx without papillae on anterior rim. Proventricle long and wide, barrel-shaped, through 4 segments, with about 22 muscle cell rows. Pygidium small, with two anal cirri similar to dorsal cirri but distinctly longer, and a median papilla (Fig. 35B).

Remarks. This species is characterized by the compound chaetae, with slender, thin blades, curved as a sabre. The most similar species is Erinaceusyllis serratosetosa, but this species can be differentiated by the size of body and the compound chaetae, which have long, curved marginal spines on the long blades.

Distribution. Australia (Queensland).

Habitat. Mud on shallow water.

Etymology. This species is named in honour of Mr Ettienne Fourie.