Exogone (Exogone) lourei Berkeley & Berkeley, 1938

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 : 129-130

Exogone (Exogone) lourei Berkeley & Berkeley, 1938

Fig. 78A–J

Exogone lourei Berkeley & Berkeley, 1938: 44 , figs. 6–12; Rioja, 1941: 703, pl. 3, figs. 10–13; Hartman, 1968: 425, figs. 1–5; Banse, 1972: 200, figs. 5a–d; Perkins, 1981: 1092; Uebelacker, 1984 (in part): 30–39, fig. 30–34a–f.

Exogone (Exogone) lourei .–San Martín, 1991a: 728, 735; Núñez et al., 1992: 45, fig. 2; Kudenov & Harris, 1995: 15, fig. 1.3.

Material examined. AUSTRALIA: WESTERN AUSTRALIA. 1 specimen, AM W26991, Goss Passage, Beacon Island, 28°25.5'S 113°47.0'E, dead branching coral substrate covered in coralline algae, 10 m, P.Hutchings, 18 May 1994. 12 specimens, AM W26992, Goss Passage, Beacon Island, 28°25.5'S 113°47.0'E, dead plate-coral substrate covered in coralline algae, 8 m, P.Hutchings, 22 May 1994. 1 specimen, AM W26993, off south end of Long Island, Beacon Island, 28°28.8'S 113°46.5'E, dead coral substrate embedded in calcareous substrate, 30 m, P.Hutchings, 22 May 1994. 7 specimens, AM W26994, off jetty near Fisheries Hut, Beacon Island, 28°25.5'S 113°47.0'E, dead coral substrate, plate-like spp., Acropora , Montipora , 12 m, P.Hutchings, 23 May 1994. 1 specimen, AM W26995, northeast entrance to Goss Passage, Beacon Island, 28°27.9'S 113°46.9'E, dead branching coral substrate, covered with coralline algae, 24 m, P.Hutchings, 25 May 1994. 2 specimens, AM W26996, off south end of Long Island, Beacon Island, 28°28.8'S 113°46.3'E, dead coral substrate covered in coralline algae, 5 m, P.Hutchings, 25 May 1994. 1 specimen, AM W26997, East Montlivet Island, 15°06'S 125°18'E, 6 m, P.Hutchings, 16 July 1988. 1 specimen, AM W26998, west side of Cassini Island, 13°57'S 125°37'E, P.Hutchings, 18 July 1988. 2 specimens, AM W26999, southwest corner of Lucas Island, 15°13'S 124°31'E, 30 m, P.Hutchings, 24 July 1988. 5 specimens, AM W27437, Lafontaine Island, Kimberley region, 14°10'S 125°47'E, 15 m, P.A. Hutchings, 19 July 1988.

Description. Body long and slender, filiform, 5.2 mm long, 0.25 mm wide, 45 chaetigers. Prostomium pentagonal; 4 large eyes in trapezoidal arrangement; antennae inserted close to each other, in line in front of anterior eyes; median antenna cylindrical with narrow tip, much longer than lateral antennae, slightly shorter than prostomium and palps together; lateral antennae ovate, about 1 ⁄ – 1 ⁄ of median 5 6 antennal length (Fig. 78A). Palps long, fused along their length, triangular with a distal notch (Fig. 78A). Peristomium similar in length to following segments; tentacular cirri similar to lateral antennae but shorter. Dorsal cirri ovate to slightly pyriform, slightly longer than lateral antennae, shorter than parapodial lobes, present on all segments (Fig. 78A). Anterior parapodia each with 1 compound spinigerlike chaeta, with unidentate, long and slender blade, 42 µm long, short marginal spines of blade and few subdistal spines on shaft (Fig. 78B); in addition 4–5 falcigers with long subdistal tooth and short distal tooth, moderately long marginal spines (Fig. 78C), 12–10 µm long. Spiniger-like chaetae of chaetiger 2 with thick shafts, provided with a triangular process with minute spines on surface, and long, about 43 µm long, distally bifid blade, with moderate to short marginal spines (Fig. 78E). Compound chaetae similar throughout but posteriorly with shorter spines and shorter blades; posterior parapodia each with 1 spiniger-like (Fig. 78G), blades 28 µm long, and 3 falcigers, blades 8–9 µm long (Fig. 78I). Dorsal simple chaetae from anterior parapodia, with rounded tips and finely spinulose subterminally (Fig. 78D), thicker posteriorly (Fig. 78F). Ventral simple chaetae on posterior parapodia, sigmoid, smooth, bidentate, subdistal tooth long and broad, distal tooth small (Fig. 78J). Acicula solitary, slender, distally rounded (Fig. 78H). Pharynx long, slender, through 6–7 segments; pharyngeal tooth on anterior margin (Fig. 78A): Proventricle shorter than pharynx, through 3 segments, with about 23 muscle cell rows. Pygidium with 2 long anal cirri.

Distribution. Pacific coasts from British Columbia to Panamá. Caribbean area: Florida, Gulf of México, Belize, Cuba. Eastern Atlantic (Canary Islands). Australia (Western Australia).

Habitat. Interstitial in coarse to medium sand. Inside dead corals. Intertidal to about 30 m depth.