Redescription of Pomatostegus stellatus (Abildgaard, 1789) and P. kroyeri Mörch 1863 (Polychaeta: Serpulidae) from the Tropical American coasts Author Sánchez-Ovando, J. Pablo Laboratorio de Sistemática de Invertebrados Marinos (LABSIM), Universidad del Mar, campus Puerto Ángel, Ciudad Universitaria, Apdo. Postal 47, Puerto Ángel, Oaxaca, 70902, México. & División de Estudios de Posgrado, Maestría en Ciencias: Ecología Marina, Universidad del Mar (UMAR), campus Puerto Ángel, Oaxaca, 70902, México. Author Bastida-Zavala, J. Rolando 0000-0003-4802-1348 Laboratorio de Sistemática de Invertebrados Marinos (LABSIM), Universidad del Mar, campus Puerto Ángel, Ciudad Universitaria, Apdo. Postal 47, Puerto Ángel, Oaxaca, 70902, México. & rolando _ bastida @ yahoo. com. mx; https: // orcid. org / 0000 - 0003 - 4802 - 1348 rolando_bastida@yahoo.com.mx text Zootaxa 2021 2021-05-17 4970 3 495 514 journal article 6257 10.11646/zootaxa.4970.3.3 5a5b8a5d-7350-4319-aa04-381e28290f43 1175-5326 4766736 7F5D66E4-C11E-4BD9-AAED-82ED93CD7C0C Genus Pomatostegus Schmarda, 1861 Type-species. Pomatostegus macrosoma Schmarda, 1861 , by subsequent designation ( Hartman 1959 ): 587–588, 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 five 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 radiolar 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. Radiolar 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 [= proximal boss] and distal blade, and limbate. Apomatus - type 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 eight teeth in profile, three teeth in a row. Achaetous anterior abdominal zone absent. Long posterior capillary chaetae absent, but posterior chaetae longer. Posterior glandular pad absent.