Tridentata turbinata (Lamouroux, 1816)

Fig. 9g

Dynamena turbinata Lamouroux, 1816: 180.

Type locality. “ Sur les Fucus de l’Australasie ” (Lamouroux 1816).

Voucher material. Fort Pierce Inlet, north jetty, north side, 27°28’24.1”N, 80°17’21.2”W, intertidal zone, on benthic algae, 14.vii.2012, 28° C, 35‰, collected manually, about four colonies, up to 1.1 cm high, without gonothecae, coll. D.R. Calder, ROMIZ B3970.

Remarks. This species has sometimes been identified as Sertularia brevicyathus (Versluys, 1899) in the western North Atlantic. However, most authors have followed Billard (1925) in assigning that binomen to the synonymy of Dynamena turbinata Lamouroux, 1816. As in earlier work (Calder 1991a), the species is referred herein to the genus Tridentata Stechow, 1920. Detailed taxonomic accounts of T. turbinata have been given elsewhere (e.g., Calder 1991a; Medel & Vervoort 1998, as Sertularia turbinata).

Reports of T. turbinata have been based most often on sterile material, and gonophores were lacking in present material from the east coast of Florida. Gonothecae of the species are barrel-shaped with transverse ridges, and with a wide terminal aperture (e.g., Stechow 1919, as Sertularia brevicyathus; Millard 1975, as S. turbinata; Hirohito 1995, as S. turbinata).

Tridentata turbinata is a hydroid of tropical and subtropical waters, extending northwards in the western North Atlantic to the Tortugas (Leloup 1935, as Sertularia turbinata), the Bahamas (Leloup 1937, as S. turbinata), and Bermuda (Calder 1991a). It has also has been reported as part of the Sargassum fauna in the region (Burkenroad, in Parr 1939, as S. brevicyathus).

Reported distribution. Atlantic coast of Florida. First record.

Western Atlantic. Fort Pierce, Florida (this study) to Brazil (Oliveira et al. submitted, as Sertularia turbinata), including Bermuda (Calder 1991a), the Gulf of Mexico (Calder & Cairns 2009), and the Caribbean Sea (Calder & Kirkendale 2005).

Elsewhere. Circumglobal in tropical and subtropical waters (Millard 1975, as S. turbinata).