Anoplosyllis Claparède, 1868

San Martin, G & Hutchings, PA, 2006, Eusyllinae (Polychaeta: Syllidae) from Australia with the Description of a New Genus and Fifteen New Species, Records of the Australian Museum 58, pp. 257-370 : 266-268

Genus Anoplosyllis Claparède, 1868

Anoplosyllis Claparède, 1868: 214 .—San Martín, 2003: 134.

Type species. Anoplosyllis edentula Claparède, 1868 , by monotypy.

Diagnosis. Body small, (<5 mm in length), with up to 30 chaetigers. Prostomium rectangular, similar width to anterior segments, with 2 pairs of eyes and 2 anterior eyespots. Three antennae. Palps small, fused basally, without median furrow. Nuchal organs as 2 ciliated grooves between prostomium and peristomium. Two pairs of tentacular cirri. Antennae, tentacular and dorsal cirri smooth, club-shaped, tapered basally, longer than parapodial lobes. Compound chaetae heterogomph, blades slender, elongate, unidentate or indistinctly bidentate.Dorsal and ventral simple chaetae present on some parapodia. Pharynx shorter than proventricle, unarmed. Proventricle large, almost as wide as body. Some species brood eggs in gelatinous masses.

Remarks. Fauvel (1923) synonymized Anoplosyllis with Syllides . Species of Syllides , however, have long, articulated cirri from chaetiger 3, and bidentate compound chaetae. Although these genera are closely related, San Martín (2003) proposed the resurrection of Anoplosyllis , and transferred species of Syllides with smooth dorsal cirri into the genus. Description. Body up to 2 mm long with 20 chaetigers; complete specimen 1.4 mm long, 0.2 mm wide, 20 chaetigers. Prostomium oval, more than twice as wide as long; 4 eyes arranged in open trapezoidal pattern and 2 distinct anterior eyespots, similar in size to eyes ( Fig. 6A). Antennae short, similar to width of prostomium, clubshaped; median antenna inserted between posterior eyes, lateral antennae near anterior margin of prostomium ( Fig. 6A). Palps small, shorter than prostomium. Tentacular cirri similar to antennae, dorsal ones longer than ventral ones. Dorsal cirri similar to antennae and tentacular cirri ( Fig. 6A), smooth, club-shaped, slightly longer than parapodial lobes, some with distinct dark inclusion ( Fig. 6B), which opens via terminal pore. Parapodial lobes elongate; ventral cirri digitiform, shorter than parapodial lobes ( Fig. 6B). Compound chaetae heterogomph, smooth, slender, blades elongate, thin, unidentate, smooth ( Fig. 6C), numbering 12– 18 per parapodium, with dorsoventral gradation in length of blades, 48 µm in length dorsally, 29 µm in length ventrally. Dorsal simple chaetae from chaetiger 1, slender, unidentate, with minute spines on margin ( Fig. 6D). Ventral simple chaetae on posterior chaetigers, similar to dorsal simple chaetae, but thinner and smooth ( Fig. 6F). Aciculae solitary, slender, distally rounded ( Fig. 6E). Pharynx partially everted, short, probably through 1–2 chaetigers. Proventricle, massive, through 4 segments ( Fig. 6A); number of muscle cell rows not possible to assess. Pygidium small, triangular, with 2 filiform anal cirri and compact median papilla.

Remarks. The Australian material is represented by a few juvenile individuals and while they closely resembles the type material of Anoplosyllis sexoculata from southern Chile, they possess a shorter proventricle. At this stage we are referring them to this species, but mature individuals are really needed to confirm this.

Habitat. Occurring interstitially in fine to coarse sand, on algae, on colonies of sabellariids; intertidally to about 20 m.

Distribution. Southern Chile, Namibia, Australia (Victoria, New South Wales).