Plumularia setacea ( Linnaeus, 1758 )

Galea, Horia R., 2010, Additional shallow-water thecate hydroids (Cnidaria: Hydrozoa) from Guadeloupe and Les Saintes, French Lesser Antilles, Zootaxa 2570, pp. 1-40 : 29

Plumularia setacea ( Linnaeus, 1758)

(figs 1H, 7J–M)

Sertularia setacea Linnaeus, 1758: 813 .

Plumularia setacea ― Calder, 1997: 17, fig. 4.

Material examined. Stn.12: 30.11.2009, 12–15 m—a few sterile plumes, to 2.3 cm high, on sponge surface; a single 1.5 cm high, sterile plume, epizoic on stolon of Sertularella diaphana ( Allman, 1885) , morphotype 1. Stn.20: 26.11.2009, 20 m—numerous stems to 16 cm high, some bearing rare gonothecae (presumably male), on sponge and dead gorgonian (part as MNHN-IK.2009-832). Stn.21: 24.11.2009, 10–15 m—numerous stems to 19 cm high, occasionally bearing presumably male gonothecae, epizoic on sponge and large colonies of S. diaphana , morphotype 1; several stems are overgrown by epizootic cladia of S. diaphana (MHNG- INVE-68730).

Remarks. There are generally two nematothecae in the axil of the cauline apophyses supporting the cladia (fig. 7J), but up to seven may occur in the basalmost internodes. Commonly a single nematotheca on side opposite to apophysis is found on the internodes, but up to three may be occasionally present. The hydrocladial ahydrothecate segments are of varied length and bear generally one nematotheca, occasionally two (fig. 7L). Auto-epizoism is quite frequent in colonies with numerous, clustered stems.

The present specimens approach, by their size and the presence of extranumerary axillar and cauline nematothecae, the material described by Calder (1997) from Bermuda.

Caribbean records. See Calder & Kirkendale (2005).

World distribution. Circumglobal except purely Arctic and Antarctic regions ( Vervoort 2006).