Hydroids (Cnidaria, Hydrozoa) from Mauritanian Coral Mounds Author Gil, Marta Departamento de Ecoloxía e Bioloxía Animal, Facultade de Ciencias do Mar e Centro de Investigación Mariña (CIM-UVigo), Universidade de Vigo. Campus Lagoas-Marcosende. 36310 Vigo. Spain. & Instituto Español de Oceanografía, Centro Oceanográfico de Vigo. Subida Radio Faro 50. 36390 Vigo. Spain. Author Ramil, Fran Departamento de Ecoloxía e Bioloxía Animal, Facultade de Ciencias do Mar e Centro de Investigación Mariña (CIM-UVigo), Universidade de Vigo. Campus Lagoas-Marcosende. 36310 Vigo. Spain. & framil @ uvigo. es Author Agís, José Ansín Departamento de Ecoloxía e Bioloxía Animal, Facultade de Ciencias do Mar e Centro de Investigación Mariña (CIM-UVigo), Universidade de Vigo. Campus Lagoas-Marcosende. 36310 Vigo. Spain. & ansinjose @ gmail. com text Zootaxa 2020 2020-11-16 4878 3 412 466 journal article 7931 10.11646/zootaxa.4878.3.2 288c6fc9-269b-468f-8811-d79d4350f6e4 1175-5326 4425132 4F59F5B2-CFDB-4819-AF83-0EF232328F8D Halecium beanii ( Johnston, 1838 ) Halecium beanii : Millard, 1975: 144-145 , figs 47A-E; Cornelius, 1995a: 276–278 , fig. 62; Ramil et al ., 1998: 7 ; Medel & Vervoort, 2000: 8–12 , fig. 1; Schuchert, 2005: 615–618 , fig. 5, 6. Material examined. MSM 16 /3, stn GeoB 14796–1, ROV, 20°14.840’– 20°14.575’N , 17°40.193’– 17°40.071’W , 487–642 m , 3-XI-2010 : three colonies 40–60 mm high, attached to Lophelia pertusa , all colonies with female gonothecae . Biology. Halecium beanii has been usually found growing on hard substrata like rocks and concretions and on algae and other invertebrates ( Gravili et al . 2015 ). Fertile material has been found throughout the year ( Cornelius 1995a ; Gil & Ramil 2017a ). Our material was found growing on L. pertusa . Colonies with female gonothecae were recorded in November. Distribution. This species shows a near cosmopolitan distribution in shallow to moderately deep waters, with records in all oceans but the Southern Ocean ( Cornelius 1995a ; Ramil et al. 1998 ; Schuchert 2005 ); its distribution was reviewed in detail by Medel & Vervoort (2000) . In West Africa, H. beanii was collected from Morocco ( Patriti 1970 ), Canary Islands ( Medel & Vervoort 2000 ), Cape Verde Islands ( Rees & Thursfield 1965 ), Guinea-Bissau (Vervoort 1959; Gili et al. 1989 ) and Ghana ( Buchanan 1957 ). Its bathymetric distribution extends from 0 to 1134 m ( Millard 1978 ). Our material was collected from depths of 487 to 642 m . Remarks. The presence of female gonothecae confirms the identification of this material as H. beanii . Its morphology is very similar to that of Halecium halecinum ( Linnaeus, 1758 ) , and only the female gonothecae allow accurate separation of both species ( Millard 1975 ; Ramil & Vervoort 1992 ; Schuchert 2005 ).