Pomatostegus Schmarda, 1861

Kupriyanova, Elena K., Sun, Yanan, Ten Hove, Harry A., Wong, Eunice & Rouse, Greg W., 2015, Serpulidae (Annelida) of Lizard Island, Great Barrier Reef, Australia, Zootaxa 4019 (1), pp. 275-353 : 303

Genus Pomatostegus Schmarda, 1861

Type-species. Pomatostegus macrosoma Schmarda, 1861 , junior synonym of Terebella stellata Abildgaard, 1789 .

Diagnosis. (from ten Hove & Kupriyanova 2009). Tube white, opaque, semi-circular to roughly triangular in crosssection, with up to 5 longitudinal keels; granular overlay absent. Operculum a very flat ampulla covered with chitinous disk bearing a column with several serrated disks alternating with circlets of spines proximally and closely applied to each disk. Peduncle flatly triangular in cross-section with broad latero-distal wings along its entire length; inserted to the left or right at the basis of the branchial lobe; from the fact that the first and second radiole separated by the base of the peduncle, it is inferred that it is derived from the second normal radiole. Constriction absent. Pseudoperculum absent. Arrangement of radioles in (semi-)circles, up to 90 per lobe. Interradiolar membrane present. Branchial eyes present. Stylodes absent. Mouth palps absent. Seven thoracic chaetigerous segments. Collar tri- to penta-lobed, well developed with an entire smooth margin. Tonguelets absent. Thoracic membranes short, ending just posterior to the second row of uncini (segment 3). Collar chaetae Spirobranchus - type, with basal pilose fin and distal blade, and limbate. Apomatus chaetae present. Thoracic uncini saw-shaped, with 9–13 teeth, anterior peg blunt. Thoracic tori meet ventrally in larger specimens; in juveniles the ventral space between thoracic tori narrowing towards last rows that almost fused, leaving a triangular depression. Abdominal chaetae flat narrow geniculate, with long blade. Abdominal uncini smaller than thoracic ones, with about 8 teeth in profile, 3 teeth in a row. Achaetous anterior abdominal zone absent. Long posterior capillary chaetae absent, but posterior chaetae longer. Posterior glandular pad absent.

Remarks. For a couple of decades, the genus was thought to be monotypic, with Pomatostegus stellatus ( Abildgaard, 1789) as single representative, occurring circumtropically. Instigated by P. Valentijn (personal communication from unpublished student's research), ten Hove & Kupriyanova (2009: 78) restricted the nominal taxon P. stellatus to the tropical Atlantic Region, and the previously synonymized P. actinoceras Mörch, 1863 , from the Indo-West Pacific Region and P. krøyeri Mörch, 1863 , from tropical Pacific America, were elevated to full species again.