Odontosyllis Claparède, 1863

Fukuda, Marcelo Veronesi, Nogueira, João Miguel De Matos, Paresque, Karla & Martín, Guillermo San, 2013, Species of Odontosyllis Claparède, 1863 (Annelida: Polychaeta: Syllidae) occurring along the Brazilian coast, Zootaxa 3609 (2), pp. 142-162 : 143

Genus Odontosyllis Claparède, 1863

Type species: S yllis fulgurans Audouin & Milne Edwards, 1833, designated by Hartman (1959).

Diagnosis. Medium to large sized body. Prostomium with two pairs of eyes and three antennae; palps fused only at bases or free, close to each other. Nuchal organs as one pair of ciliated rows extending along posterior border of prostomium. Peristomium with two pairs of cirri; rounded occipital flap usually present, frequently well developed, extending over posterior part of prostomium, covering dorsal end of nuchal organs. Antennae, peristomial and dorsal cirri throughout smooth to irregularly wrinkled, usually distally tapering. Compound chaetae as uni- or bidentate falcigers, elongated in some species. Pharynx usually short; trepan with teeth directed backwards and, frequently, two lateral plates; pharyngeal central tooth absent. Reproduction by epigamy; epitokes frequently bioluminescent.

Remarks. Odontosyllis is a relatively large genus of syllids, currently with about 49 valid species (Verdes et al. 2011), relatively easily recognized by the morphology of the trepan, with backwards directed teeth, and by the usual presence of an occipital flap extending over the posterior part of prostomium.

In many species of this genus (including all the Brazilian ones), the dorso-ventral gradation in length of the falciger blades is opposite to that usually found in syllids (i.e., the dorsalmost falciger blades are shorter than the ventralmost ones). This feature was misinterpreted in Fukuda & Nogueira (2006) and is usually not mentioned in species descriptions.