Nemertesia ramosa ( Lamarck, 1816 )

Gil, Marta & Ramil, Fran, 2025, Hydroids (Cnidaria, Hydrozoa) from Guinea Bissau, Zootaxa 5577 (1), pp. 1-89 : 68

Nemertesia ramosa ( Lamarck, 1816)

Antennularia ramosa Lamarck, 1816: 123 .

Nemertesia ramosa : Ramil & Vervoort, 1992a: 173–176, fig. 44A–F.— Cornelius, 1995b: 155–156, fig. 36.— Ansín Agís et al., 2001: 215–222, fig. 83–84.— Peña Cantero & García Carrascosa, 2002: 115–117, fig. 22D–F.— Gravili et al., 2015: 125–126 , fig. 89A–E.

Material examined. BISSAU-0810, stn BS147, 11º08'35"– 11º08'27"N, 17º11'31"– 17º10'37"W, 186–306 m, 26-X-2008: two colonies (one with gonothecae), 80–98 mm high, of which one growing on a worm tube.

BISSAU-0810, stn BS151, 11º05'09"– 11º04'15"N, 17º03'15"– 17º03'10"W, 46–47 m, 26-X-2008: one colony without gonothecae, 105 mm high, substrate unknown.

BISSAU-0810, stn BS152, 10º31'12"– 10º30'19"N, 17º12'34"– 17º12'32"W, 300–305 m, 27-X-2008: five colonies without gonothecae, 63–175 mm high, substrate unknown.

BISSAU-0810, stn BS157, 10º19'36"– 10º18'44"N, 17º10'29"– 17º10'12"W, 304–308 m, 28-X-2008: six colonies without gonothecae, 90–320 mm high, of which one growing on a worm tube.

BISSAU-0810, stn BS174, 10º01'42"– 10º02'16"N, 17º00'52"– 17º01'35"W, 419 m, 31-X-2008: one colony without gonothecae, 235 mm high, growing on a worm tube.

BISSAU-0810, stn BS195, 10º22'44"– 10º23'22"N, 16º15'37"– 16º16'18"W, 29 m, 3-XI-2008: one colony without gonothecae, 49 mm high, substrate unknown.

BISSAU-0810, stn BS199, 10º16'49"– 10º17'29"N, 16º22'15"– 16º22'49"W, 65–70 m, 4-XI-2008: 13 colonies (some with gonothecae), 110–206 mm high, substrate unknown.

BISSAU-0810, stn BS200, 10º18'55"N, 16º25'07"W, 79 m, 4-XI-2008: two colonies without gonothecae, 74– 119 mm high, substrate unknown.

BISSAU-0810, stn BS216, 10º30'53"– 10º31'39"N, 16º31'33"– 16º32'02"W, 56–58 m, 7-XI-2008: four colonies without gonothecae, 90–170 mm high, substrate unknown.

CCLME-1110, stn BT40, 10º15'45"– 10º14'39"N, 16º55'17"– 16º54'05"W, 224 m, 27-X-2011: one colony without gonothecae, 15 mm high, substrate unknown.

CCLME-1110, stn BT49, 10º57'13"– 10º58'26"N, 16º59'29"– 17º00'29"W, 62 m, 29-X-2011: one colony without gonothecae, 14 mm high, growing on a polychaete tube.

Remarks. Nemertesia ramosa is a well-known species in the East Atlantic and does not require further comments.

Biology. Nemertesia ramosa has been mainly collected from non-living hard substrates, but also as an epizoite of other hydroids, anthozoans, bivalves, decapod crustaceans, as well as growing directly on muddy bottoms ( Peña Cantero & García Carrascosa 2002; Gravili et al. 2015). In the northern hemisphere, fertile material has been collected from January to October and December ( Ansín Agís et al. 2001; Peña Cantero & García Carrascosa 2002), while in the southern hemisphere, gonothecae were observed in September ( Millard, 1957).

In our material, some colonies were found growing on worm tubes. Gonothecae were observed in October and November.

Distribution. East Atlantic species distributed from Iceland and Norway to South Africa ( Calder 2012). In West Africa, it has been recorded from Morocco, Western Sahara, Mauritania, Gambia, the Cape Verde Archipelago, Guinea-Bissau, the Republic of Guinea, the Ivory Coast, Ghana and Namibia ( Ansín Agís et al. 2001). Its bathymetric distribution ranges from 3 to 1425 m ( Ansín Agís et al. 2001; Peña Cantero & García Carrascosa 2002).

Our material was collected at depths between 29–308 m.