The polyclads (Platyhelminthes: Polycladida) from the Tropical Eastern Pacific: Commented checklist and description of a new species Author Ramos-Sánchez, Mariela E9D05B3F-CF64-48E3-B5ED-8D24E47F9D2A Doctorado en Ciencias Biológico Agropecuarias, Área Ciencias Biológico Agropecuaria y Pesquera, Ciudad de la cultura “ Amado Nervo ”, Tepic, Nayarit, 63000, Mexico. & Laboratorio de Sistemática de Invertebrados Marinos (LABSIM), Universidad del Mar, campus Puerto Ángel, Ciudad Universitaria, Puerto Ángel, Oaxaca, 70902, Mexico. rmariela220@gmail.com text European Journal of Taxonomy 2024 2024-10-17 962 1 1 67 https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2683/12419 journal article 10.5852/ejt.2024.962.2683 2118-9773 13947260 40171C5B-90EB-4641-91FF-EA8CA2C60D23 Alloioplana stylifera (Hyman, 1953) Zygantroplana stylifera Hyman, 1953a: 308–309 , figs 53–54 ( type locality: Puerto Refugio, Ángel de la Guardia Island, Baja California , Mexico ). Alloioplana stylifera – Faubel 1983: 101 (new combination, identification keys). — Brusca 2005: 69 (checklist). Distribution Puerto Refugio, Ángel de la Guardia Island, Baja California ; Tiburón Island, Sonora , Mexico . Habitat Benthic. Remarks Alloioplana stylifera was initially described by Hyman (1953a) within the genus Zygantroplana , while Faubel (1983) transferred it to the genus Alloioplana , based on the presence of separate gonopores, a seminal vesicle,an interpolated prostatic vesicle, an armed penis papilla, and Lang’s vesicle. Alloioplana stylifera is characterized by an oblong body with a truncated posterior end, absence of nuchal tentacles, presence of cerebro-tentacular eyes, an elongated pharynx, and separate gonopores located in the terminal region of the body. The seminal vesicle are rudimentary, the penis papilla is armed with a thin and prominent stylet (in proportion of the same size as the vagina), the elongated tubular vagina is oriented towards the posterior-dorsal region of the body.