Syllidia

Rizzo, Alexandra E. & Salazar-Vallejo, Sergio I., 2014, Hesionidae Grube, 1850 (Annelida: Polychaeta) from South-Southeastern Brazil, with descriptions of four new species, Zootaxa 3856 (2), pp. 267-291 : 273

Syllidia de Quatrefages, 1865

Syllidia de Quatrefages, 1865:291, 1866: 13; Pleijel, 1998: 124 –126; Ruta & Pleijel, 2006: 506 . Type species: Syllidia armata de Quatrefages, 1866, by monotypy.

Diagnosis (modified from Pleijel 1998, and Ruta & Pleijel 2006): Hesioninae with eyes, small facial tubercle, and ovoid palpostyles. Ventral proboscis incision present, terminal ring of proboscis with 10 papillae, paired lateral jaws, and median stylet present, proboscis diaphragm absent. Lip glands absent or present (uncertainty). Enlarged dorsal cirri on segments 1–5, enlarged ventral cirri on segments 1–3, with alternation in orientation/length—non-elevated dorsal cirri on segment 22; elevated dorsal cirri on segments 23, 26 and 30 (Group IIIb2, see Pleijel 1998: 98, Table 3). Emerging notopodial hooks absent, notochaetae absent. Neuropodial lobes and neurochaetae from segment 3 or 4. Neurochaetal blades with prolonged teeth; tips unidentate. Paired ventral segmental adhesive papillae absent. Median pygidial papillae present.

Remarks. Ruta & Pleijel (2006) revised Syllidia ; they described a new species from Hong Kong but regarded all other species as junior synonyms of S. armata , originally described from the Atlantic French coast. The two valid species show interesting differences regarding the development of jaws, and their posterior projections, such that these features could separate other species; because other body features might be more conservative, the modifications of jaws and chaetae should be more widely used to clarify the affinities of different populations or species (see below).