Pionosyllis Malmgren, 1867

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 : 322-323

Genus Pionosyllis Malmgren, 1867

Pionosyllis Malmgren, 1867: 40 .

Type species. Pionosyllis compacta Malmgren, 1867 by monotypy.

Diagnosis. Body ranges from meiofaunal to macrofaunal size (<5 to> 10 mm in length), dorsally convex. Prostomium with 4 eyes, sometimes also pair of eyespots, sometimes without eyes. Three antennae. Prostomium sometimes with cheeks or lobes on large specimens. Median antenna inserted on middle of prostomium or anteriorly. Palps fused at bases, with dorsal furrow, or free from each other. Two pairs of tentacular cirri. Nuchal organs as 2 ciliated grooves between prostomium and peristomium.Antennae, tentacular cirri and dorsal cirri smooth, sometimes rugose, long, filiform, all similar; weakly articulated on some species. Ventral cirri not fused to parapodial lobes, those of anterior parapodia somewhat inflated on some species, inserted basally or distally on parapodial lobes. Heterogomph compound chaetae with bidentate falcigerous blades, teeth similar in size; some dorsal anterior and midbody falcigers slightly longer than others, decreasing in size in dorsoventral gradation within fascicle; some species with hemigomph or homogomph articulations and blades of compound chaetae different to those described above. Dorsal and ventral simple chaetae on some posterior parapodia, bidentate, with both teeth similar, sometimes absent. Parapodia with or without prechaetal lobes. Pharynx and proventricle similar in size. Pharyngeal tooth anteriorly located, some species with tooth on middle of pharynx. Reproduction by epigamy. Pygidium small, with 2 smooth anal cirri.

Remarks. Pionosyllis as above defined is a heterogeneous, probably a polyphyletic group in need of revision. Currently, GSM and other authors are preparing a major revision of the group.