Clytia elsaeoswaldae Stechow, 1914

Calder, Dale R., 2013, Some shallow-water hydroids (Cnidaria: Hydrozoa) from the central east coast of Florida, USA, Zootaxa 3648 (1), pp. 1-72 : 54-55

Clytia elsaeoswaldae Stechow, 1914

Fig. 15e

Clytia elsae-oswaldae Stechow, 1914: 125 , fig. 4.

Type locality. U.S. Virgin Islands: St. Thomas , Charlotte Amalie ( Stechow 1914) .

Voucher material. Off St. Lucie Inlet, 27°10.7’N, 80°02.7’W, on Eudendrium carneum , 23 m, vii.1975, Johnson-Sea-Link, JSL 274, one colony, up to 4 mm high, with gonophores, coll. T. Askew, ROMIZ B1134 .

Remarks. Lindner et al. (2011) have been followed in recognizing Clytia elsaeoswaldae Stechow, 1914 (type locality: St. Thomas) as distinct from Clytia gracilis (M. Sars, 1850) (type locality: Norway). Suspicions had been raised earlier, on zoogeographic grounds, that the two might be distinct ( Calder 1991a: 57). As with material of Lindner et al. from Brazil and type material from the U.S. Virgin Islands, gonothecae of hydroids from Florida examined here were borne on the stolons or mostly so. The species appears to be endemic to shallow-waters of the warm western Atlantic. Material earlier identified as C. gracilis by me ( Calder 1991a) from Bermuda is referable to the same species. A phylogenetic analysis by Lindner et al. (2011) indicates that C. elsaeoswaldae is related phylogenetically to C. hemisphaerica ( Linnaeus, 1758) and to several species resembling C. gracilis .

Clytia elsaeoswaldae is distinguished in part by the following combination of characters: (1) colonies are stolonal, or erect with monosiphonic and dichotomously branched hydrocauli; (2) hydrothecae have about 9–14 cusps that are usually inclined to the right when viewed laterally; (3) gonothecae tend to arise from the hydrorhiza, and have smooth to slightly undulated walls ( Lindner et al. 2011).

The hydroid examined here was growing as an epizoite on a stem of Eudendrium carneum Clarke, 1882 . Its stolons were entangled with those of a colony of C. linearis ( Thornely, 1900) , discussed below.

Reported distribution. Atlantic coast of Florida. First record.

Western Atlantic. Bermuda ( Calder 1991a, as Clytia gracilis ) to Brazil (Oliveira et al. submitted), and including the Caribbean Sea ( Stechow 1914).

Figures

FIGURE 15. a, Campanularia macroscypha: part of colony with hydrotheca, ROMIZ B1101, scale equals 0.5 mm. b, Campanularia macroscypha: hydrotheca and distal part of pedicel, ROMIZ B1101, scale equals 0.20 mm. c, Orthopyxis sargassicola: hydrotheca and distal part of pedicel, ROMIZ B1123, scale equals 0.20 mm. d, Orthopyxis sargassicola: gonotheca, ROMIZ B1123, scale equals 0.20 mm. e, Clytia elsaeoswaldae: part of a colony with hydrotheca and gonotheca, ROMIZ B1134, scale equals 0.25 mm. f, Clytia linearis: hydrotheca and distal part of pedicel, ROMIZ B3983, scale equals 0.25 mm.