Acryptolaria conferta ( Allman, 1877 )

Gil, Marta & Ramil, Fran, 2025, Hydroids (Cnidaria, Hydrozoa) from Guinea Bissau, Zootaxa 5577 (1), pp. 1-89 : 22-23

Acryptolaria conferta ( Allman, 1877)

( Fig. 3C )

Cryptolaria conferta Allman, 1877: 17–19 , pl. XII figs 6–10.

Oswaldaria conferta : Leloup, 1940:15.

Acryptolaria conferta : Rees & White, 1966: 273.— Patriti, 1970: 30, fig. 33.— Vervoort, 1972: 44–45, fig. 12A.— Vervoort, 2006: 226–227.

Acryptolaria conferta conferta : Calder, 1991: 33–35, figs 19–20.— Ramil & Vervoort, 1992a: 41–43, fig. 7A–B.

Material examined. BISSAU-0810, stn BS131, 11º34'07"– 11º33'13"N, 17º11'25"– 17º11'31"W, 102–103 m, 23-X-2008: one colony, 60 mm high, without gonothecae.

Remarks. The material studied herein agrees with those described by Ramil & Vervoort (1992a) as Acryptolaria conferta conferta ( Allman, 1877) . We followed Peña Cantero et al. (2007), and studied the cnidome of our specimens that revealed two size classes of the same type of nematocysts, larger capsules (14–17 μm long, 5–6 μm wide) and smaller capsules (7–8 μm long, 3–4 μm wide). Upon a comparison with Acryptolaria conferta var. minor Ramil & Vervoort, 1992 , collected during the SEAMOUNT-1 expedition, it was realized that the nematocysts of the latter were of the same type as those of A. conferta conferta , but differing in size, viz. (18–19 μm long, 6–7 μm wide) and (9–11 μm long, 4–8 μm wide), respectively.

This difference between the nematocysts of the two morphotypes, together with the size range observed by Ramil & Vervoort (1992a) and the absence of intermediate forms ( Gil et al. 2020) seems to reinforce the separation of these so-called two varieties.

This is the first time that the nematocysts of both forms have been studied, and it appears that the cnidome is a reliable character to be used whenever possible. Our finding represents the first record of A. conferta var. conferta for Guinea-Bissau.

Biology. This species has been reported growing on different substrates, such as bryozoans, sponges, coral fragments and stones ( Ramil & Vervoort 1992a; Vervoort 2006). In the northern hemisphere, coppiniae have been found from May to July ( Ramil & Vervoort 1992a; Calder 1991; Vervoort 2006).

Distribution. Acryptolaria conferta conferta is a circumglobal species occurring in moderately deep to deep waters ( Vervoort 2006). In West Africa, it has been collected from Morocco ( Patriti 1970; Ramil & Vervoort 1992a) and Mauritania ( Vervoort 2006; Gil & Ramil 2017a). Its bathymetric distribution ranges from 52 to 2050 m ( Vervoort 2006).

Our material was collected at depths between 102–103 m.

Genus Filellum Hincks, 1869

Figures

FIGURE 3. A. Lovenella corrugata Thornely, 1908 (stn BS191), portion of colony with hydrothecae and a gonotheca. B. Plicatoteca anitae Calder & Vervoort, 1986 (stn BS152), portion of colony. C. Acryptolaria conferta (Allman, 1877) (stn BS131), portion of hydrocladium. D. Lafoea gracillima (Alder, 1856) (stn BS152), portion of colony with hydrothecae. Scales: a–d, 0.5 mm.