Semivermilia

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 : 311

Genus Semivermilia ten Hove, 1975

Type-species. Vermiliopsis pomatostegoides Zibrowius, 1969

Diagnosis. (from ten Hove & Kupriyanova 2009). Tube triangular to sub-triangular in cross-section, keels present, otherwise variable; without flaring peristomes; granular overlay absent. Operculum inverse conical with chitinous endplate, more often a cap or series of diabolo-like plates; sometimes with terminal spine. Peduncle inserted as second radiole, cylindrical in cross-section; constriction present. Pseudoperculum absent. Radiolar arrangement short pectinately, up to 7 radioles per lobe. Inter-radiolar membrane absent. Branchial eyes may be present. Stylodes absent. Mouth palps present. Five to seven thoracic chaetigerous segments. Collar tri- to penta-lobed, tonguelets absent. Thoracic membranes end at chaetiger 2. Collar chaetae limbate. Apomatus chaetae present on posterior thoracic segments. Thoracic uncini saw- to-rasp-shaped; with about 15 teeth in profile view, 1 tooth at the apex of the uncinus to 5 teeth in the row above the wide gouged peg (dental formula e.g., P:5:3:2:2:1:1:1:1:1:1:1:1:1:1). Triangular depression absent. Abdominal chaetae flat narrow geniculate, with rounded teeth on edge; abdominal uncini smaller than thoracic ones, entirely rasp-shaped, with about 13 teeth in profile view, up to 8 teeth in a row. Achaetous anterior abdominal zone, if present, very short. Long posterior capillary chaetae absent. Posterior glandular pad may be present.

Remarks. See remarks under Pseudovermilia . The nominal genus includes 8 species, opercula of which are characterised by elongated distal chitinous caps made of series of diabolo-like plates ( S. elliptica , S. parapomatostega , S. pomatostegoides , and S. uchidai ,), by simple caps or plates without terminal spine ( S. cribrata , S. agglutinata , S. torquata ) or with flattened endplate with terminal spine ( S. crenata ). The tubes of these species are more distinct and often allow specific recognition better than opercula do.