Exogone (Sylline) simplex Hartmann-Schröder, 1960

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 : 146

Exogone (Sylline) simplex Hartmann-Schröder, 1960

Fig. 92A–E

Exogone simplex Hartmann-Schröder, 1960: 107 , figs. 134–136; 1979: 109, figs. 169–170; 1980a: 56; 1981: 38; 1990: 55.

Material examined. WESTERN AUSTRALIA. 1 specimen, Broome, ZHM, P-16703, intertidal sand, G. Hartmann-Schröder, 23 Sept 1975.

Description. Body small, filiform, up to 2.3 mm long, 0.4 mm wide, 21 chaetigers. Prostomium oval; 4 small eyes in trapezoidal arrangement. Antennae small, originating close to each other near middle of anterior margin of prostomium ( Fig. 92A ); lateral antennae papilliform, median antenna slightly longer than lateral antennae ( Fig. 92A ). Palps, broad, fused along their length ( Fig. 92A ). Peristomium similar in length to following segments, covering posterior part of prostomium; tentacular cirri minute, smaller than lateral antennae. Dorsal cirri ovoid, shorter than parapodial lobes, absent on chaetiger 2 ( Fig. 92A ). Parapodia each with 3 chaetae lacking blades, distally spinose ( Fig. 92C ). Dorsal simple chaetae from anterior parapodia, smooth, unidentate ( Fig. 92B ). Ventral simple chaetae sigmoid, bidentate, with distal tooth shorter than distal tooth, smooth ( Fig. 92D ). Acicula solitary, slender, distally rounded, provided with a short tip ( Fig. 92E ). Pharynx short and relatively wide, through 3 segments ( Fig. 92A ); pharyngeal tooth on anterior margin ( Fig. 92A ). Proventricle short, through 2 segments, with 12–16 muscle cell rows. Pygidium with 2 long anal cirri.

Distribution. Red Sea. Australia (Western Australia, New South Wales).

Habitat. On algae, fine sand. Intertidal and shallow water.

Figures

Fig. 92. Exogone (Sylline) simplex. (A) anterior end, dorsal view. (B) dorsal simple chaeta. (C) chaetae lacking blades. (D) ventral simple chaeta. (E) acicula. Scale A: 0.1 mm, B–E: 20 µm.