Cordylophora caspia ( Pallas, 1771 )

Calder, Dale R., 2012, On a collection of hydroids (Cnidaria, Hydrozoa, Hydroidolina) from the west coast of Sweden, with a checklist of species from the region 3171, Zootaxa 3171 (1), pp. 1-77 : 9

Cordylophora caspia ( Pallas, 1771)

Fig. 5

Tubularia caspia Pallas, 1771: 479 .

? Cordylophora caspia .— Jägerskiöld, 1971: 61.

Type locality. Caspian Sea ( Pallas 1771: 479).

Museum material. Krokstrand, 59°00’49”N, 11°27’30”E, 1 m, 08.ix.2010, collected manually, on submerged wood, one colony, 1.2 cm high, with two hydranths, without gonophores, coll. Dennis P. Gordon, ROMIZ B3904 .

Remarks. Cordylophora caspia ( Pallas, 1771) is one of the few species of hydroids that thrives in the upper reaches and headwaters of estuaries, and it also extends into fresh waters. It was found during this study in a brackish water environment at Krokstrand, in a fjord NE of Strömstad. The only previous record of this brackish and fresh-water species from western Sweden is that by Jägerskiöld (1971: 61) from a station in the middle Kattegat. Although the identification was made by a reliable hydrozoan specialist (P.L. Kramp), the report needs verification given the salinity at the area (19.79 ‰ surface; 34.05 ‰ bottom). Although infrequent in western Sweden, C. caspia is widespread in the Baltic Sea (e.g. Lindstrom 1856a: 72, as C. lacustris ; Stechow 1927: 305, as C. lacustris ; Broch 1928: 48, 55; Thiel 1970: 479; Schönborn et al. 1992: 215). It has also been reported from several brackish water areas in Denmark ( Kramp 1935b). Species of Cordylophora von Lendenfeld, 1885 are familiar as invasives, and crypsis is also well-known to exist in the genus. Recent accounts of this species include those of Schuchert (2004), Folino-Rorem et al. (2009), and Calder (2010).

Reported distribution. West coast of Sweden.—Middle Kattegat (?) ( Jägerskiöld 1971).

Elsewhere.—Worldwide ( Schuchert 2004; Calder 2010).

Figures

FIGURE 5. Cordylophora caspia: part of colony with hydrocaulus and hydranth, ROMIZ B3904. Scale equals 0.5 mm. FIGURE 6. Clava multicornis: hydranth with gonophores, ROMIZ B3892. Scale equals 0.5 mm.