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 Eudendrium ramosum ( Linnaeus, 1758 ) Eudendrium ramosum : Ramil & Vervoort, 1992: 20–21 ; Schuchert, 2001: 32–33 , fig. 20; Peña Cantero & García Carrascosa, 2002: 37–38 , fig. 7a–c; Bouillon et al ., 2006: 60–61 , figs 36H–L; Vervoort, 2006: 215–216 , fig. 4 no. 2; Schuchert, 2012: 322–323 , fig. 281. Material examined. MAURIT-0911, stn MU DR01 , 16º08´24”N , 16º57´12”W , 488 m , 5-XII-2009 : 25 colonies, badly damaged, some attached to other hydroids and bryozoans . MAURIT-1011, stn MU DR20 , 16º08´11”N , 16º56´08”W , 405 m , 7-XII-2010 : two colonies badly damaged, one colony attached to a sponge and the other attached to Sertularella gayi . MSM 16 /3, stn GeoB 14802–1, BG, 20°14.791’N , 17°40.188’W , 595 m , 3-XI-2010 : two colonies without gonozooids, attached to corals . MSM 16 /3, stn GeoB 14886–1, ROV, 18°39.013’– 18°38.476’N , 16°43.580’– 16°43.757’W , 484–640 m , 12-XI- 2010 : one colony 17 mm high with female gonophores, growing on Acesta excavata . MSM 16 /3, stn GeoB 14905–1, CKG, 17°32.457’N , 16°39.997’W , 486 m , 15-XI-2010 : one colony, without gonozooids . Biology. This species grows on a wide variety of substrates, especially on hard substrata, algae and as epibiont on other invertebrates ( Peña Cantero & García Carrascosa 2002 ). Fertile material has been found from March to December ( Peña Cantero & García Carrascosa 2002 ; Schuchert 2012 ; Gil & Ramil 2017a ). In our material, some colonies were collected growing on the bivalve A. excavata and the hydroid S. gayi . Female gonophores were observed in November. Distribution. Eudendrium ramosum was reported as a cosmopolitan species by Bouillon et al. (2006) , but many of its records are considered doubtful ( Ramil & Vervoort 1992 ; Marques et al. 2000 ; Schuchert 2001 ; Peña Cantero & García Carrascosa 2002 ). Schuchert (2012) indicated that all records outside the East Atlantic (Arctic to South Africa , including the Mediterranean) need confirmation. In West Africa, it was collected from Morocco ( Ramil & Vervoort 1992 ; Vervoort 2006 ), Canary Islands ( Vervoort 2006 ), Mauritania ( Gil & Ramil 2017a ) and Cape Verde ( Ritchie 1907 ; Vervoort 2006 ). The bathymetrical distribution of the species extends from tidal areas ( Ansín Agís 1992 ) to a depth of 1870 m ( Ramil & Vervoort 1992 ). The material studied by us was collected from depths of 484 to 640 m . Remarks. The study of the nematocysts confirms that our material belongs to E. ramosum .