Exogone (Exogone) dispar (Webster, 1879)

Linero-Arana, Ildefonso & Diaz Diaz, Oscarn, 2011, Syllidae (Annelida, Polychaeta) from the Caribbean coast of Venezuela, ZooKeys 117, pp. 1-28 : 7-8

Exogone (Exogone) dispar (Webster, 1879) Figs 2.6-2.10

Paedophylax dispar Webster 1879:223, pl.4, fig. 49, pl.5, figs. 50-55.

Exogone dispar Day1973:33.- Pettibone 1963:130-131, fig. 35d.-Taylor, 1971:201 –204.– Westheide 1974:106, figs. 48 A–H, 49 A–D.– Gardiner 1976:132, fig. llf–i.– Perkins 1981:1090.- Uebelacker 1984:42-43, fig. 36 a–e.

Exogone (Exogone) dispar Ruíz-Ramírez and Salazar-Vallejo 2001:127, fig. 3(45 –54).– San Martín and Bone 2001:612.- San Martín 2003:274-276, figs. 149, 150. - 2005:137-138, figs. 81F, 85 A–G.

Material examined.

GCPG198, (4), fine sand, 1 m depth; BMER203, (2), fine sand, 4 m depth; PALB104, (16), sand with Gemma gemma (Totten 1834) ( Bivalvia : Veneridae ), 1 m depth; BMIL197, (6); BMIL498, (12); BMIL602, (3); all specimens associated with Aplysina fistularis ,1-3 m depth; BMPL197, (12), BMIL602 (8), associated with Ircinia felix , 1-2 m depth.

Description.

Length to 6.2 mm, width to 0.4 mm. Body relatively long, with up to 41 chaetigers. Prostomium with two pairs of lentigerous eyes. Median antenna fusiform, lateral antennae small, ovoid. Palps fused dorsally. All cirri ovoid. Dorsal cirri on all chaetigers. Dorsal simple chaeta blunt with subdistal spines (Fig. 2.6), present from chaetiger 1. Dorsal compound pseudospinigers serrated, slightly bifid, on anterior chaetigers (Fig. 2.7), (Fig. 2.8); compound falcigers bidentate with small distal tooth, and spines on the shaft-head (Fig. 2.9). Ventral simple chaeta bidentate with small distal tooth, only present on posterior chaetigers (Fig. 2.10). Pharynx extending through 4 chaetigers, with marginal crown of papillae, and subterminal dorsal tooth. Proventriculus extending through 4 chaetigers, with 19-22 rows of muscle cells. Pygidium with a pair of cirriform, relatively long cirri.

Remarks.

From hard bottom substrats of Trinidad and Tobago islands is the most abundant species ( Gobin 2010).

Distribution.

North Pacific, Galapagos Islands, South Japan, Australia, North Atlantic, Mediterranean, Arctic, Alaska to Mexico, South Africa, Maine to Florida, Gulf of Mexico, Trinidad & Tobago, Venezuela.