Ophelina Orsted 1843

Genus Ophelina Örsted, 1843

Type species: Ophelina acuminata Örsted, 1843, by monotypy.

Diagnosis (after Maciolek & Blake 2006). Body elongate, not divided into distinct regions; with deep ventral groove and two lateral grooves along entire length of body. Prostomium conical, sometimes with terminal palpode; eyes present or absent. Branchiae present or absent; if present, beginning on chaetiger 2, continuing to posterior end, sometimes absent from middle or far posterior chaetigers; branchiae single, cirriform. Segmental lateral eyes absent. Noto- and neuropodia with small fascicles of capillary chaetae; small ventral cirrus present. Pygidium with anal funnel sometimes bearing long unpaired cirrus and additional marginal papillae.

Remarks. There are 49 species of Ophelina considered as valid (Read & Fauchald 2018). Species of Ophelina share many similarities with Armandia by the elongate and fusiform body, not divided into distinct regions. Both genera also have similar structures associated to the anal tube, such as marginal and ventral appendages. The presence of lateral eyes in Armandia is the main distinctive feature from Ophelina. Among the opheliids, the genus Ophelina is the most diverse and consequently includes species with the most variation of morphological features.