Eudendrium capillare Alder, 1856

Gil, Marta & Ramil, Fran, 2025, Hydroids (Cnidaria, Hydrozoa) from Guinea Bissau, Zootaxa 5577 (1), pp. 1-89 : 15-16

Eudendrium capillare Alder, 1856

Eudendrium capillare Alder, 1856: 355–356 , pl. 12 figs 9–12.— Ramil & Vervoort, 1992a: 18–19, fig. 1B–C.— Marques et al., 2000: 88, figs 28–34.— Peña Cantero & García Carrascosa, 2002: 27–29, fig. 4A–B.— Schuchert, 2008: 740–744, fig. 34.— Schuchert, 2012: 334–335, fig. 287.

Material examined. BISSAU-0810, stn BS191, 10º18'25"– 10º19'20"N, 16º08'47"– 16º08'47"W, 24–25 m, 3-XI-2008: 1363 colonies (871 with gonophores), 6–49 mm high, of which 368 growing on Idiellana pristis , 314 on bryozoans, 108 on Diphasia digitalis , 40 on Tridentata loculosa , 16 on worm tubes, 10 on unidentified hydroids, nine on crustaceans, eight on Tridentata marginata , five on Dynamena disticha , five on Tridentata turbinata , four on Eudendrium ramosum , four on bivalves, one on Bimeria vestita , one on Halecium lankesteri , one on Halecium sp. and one on Clytia gracilis .

BISSAU-0810, stn BS194, 10º21'59"– 10º22'36"N, 16º13'23"– 16º14'03"W, 21–24 m, 3-XI-2008: six colonies without gonophores, of which one growing on Eudendrium sp.

Remarks. The nematocysts in our material, microbasic euryteles and isorhizas, correspond to those described for this species by Schuchert (2008, 2012).

Records of this species from Ghana ( Vervoort 1959, as Eudendrium cf. capillare ) are considered as doubtful, because the material was identified on general morphological grounds solely; moreover, all colonies were sterile.

Our finding represents the first record of this species for Guinea-Bissau.

Biology. This species grows on a variety of substrates such as algae, and on invertebrates, such as sponges, hydroids, cirripeds, mollusk shells, bryozoans and ascidians ( Peña Cantero & García Carrascosa 2002; Schuchert 2012). In the northern hemisphere, fertile material was found from April to November ( Schuchert 2008, 2012).

In our material, some colonies had gonophores in November. Most of the colonies were found growing on hydroids, bryozoans, bivalves, crustaceans and polychaete tubes.

Distribution. Eudendrium capillare is considered as nearly cosmopolitan, but many records are doubtful because they are not based on the study of the nematocysts ( Schuchert 2012). Therefore, when the records based on the cnidome are taken into account, E. capillare shows a circumglobal distribution ( Schuchert 2008). In West Africa, it has been recorded from Morocco ( Ramil & Vervoort 1992a; Vervoort 2006), Mauritania ( Billard 1906a) and Ghana ( Vervoort 1959). Its bathymetric distribution ranges from 0 to 80 m ( Schuchert 2012).

Our material was collected at depths between 21–25 m.