Tridentata turbinata ( Lamouroux, 1816 )

Calder, Dale R., 2019, On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689 (1), pp. 1-141 : 86-87

Tridentata turbinata ( Lamouroux, 1816)

Fig. 21g

Dynamena turbinata Lamouroux, 1816: 180 .

Sertularia turbinata .— Leloup, 1935a: 50.— Van Gemerden-Hoogeveen, 1965: 38.

Type locality. Australasia: on “ Fucus ” ( Lamouroux 1816: 180, as Dynamena turbinata ).

Material examined. Sanibel Island, beach at Lighthouse Point, 26°26’58”N, 82°01’04.5”W, on stranded Sargassum pteropleuron , 21 March 2018, 22° C, 34.5‰, two colonies, up to 9 mm high, without gonophores, coll. D. Calder, ROMIZ B4393.

Remarks. Tridentata turbinata is a species of tropical and subtropical waters that has been recorded but few times along the Atlantic and Gulf coasts of the United States. In inshore waters, it has not been reported north of Florida along the east coast except as colonies transported northwards on pelagic Sargassum by the Gulf Stream (e.g., Stachowicz & Lindquist 1997). It has been reported twice from Louisiana in the northern Gulf of Mexico, although one of those occurrences was based on specimens from gulfweed (pelagic Sargassum ) ( Cary & Spaulding 1909). Most distribution records listed below of T. turbinata in the North Atlantic are from the Caribbean region, although the species is also well-known from Bermuda and the Bahamas. To the south, records of the species are frequent in warm waters of coastal Brazil ( Oliveira et al. 2016). As records below also indicate, it is most common in shallow waters.

This species has long been misassigned to a non-monophyletic genus Sertularia Linnaeus, 1758 instead of Tridentata Stechow, 1920 . As documented earlier (Calder 1990 [1991a]: 104, 2013: 33; Calder et al. 2019), significant morphological differences exist between those two genera in both trophosome and gonosome. Molecular phylograms such as those in Moura et al. (2011) and Maronna et al. (2016) reveal that T. turbinata is very close genetically to T. perpusilla ( Stechow, 1919) , type species of Tridentata , and that both species are remote from S. argentea Linnaeus , type species of Sertularia . It bears repeating, once again, that the valid name of the species should be Tridentata turbinata .

The hydroid of T. turbinata is relatively common in shallow waters of the Atlantic, Pacific, and Indian oceans, yet specimens with gonothecae have been reported infrequently. Humara-Gil & Cruz-Gómez (2018: 466, figs. 8B, E) recently discovered fertile colonies from Oaxaca, Mexico, as did Galea & Ferry (2015: 235, fig. 6G, as Sertularia turbinata ) from Guadeloupe. Earlier accounts of colonies with gonothecae include those of Stechow (1919: 93, fig. H 1, as Sertularia brevicyathus ) from the Tonga Islands, Vervoort (1959: 277, figs.36b, c, as Sertularia turbinata ) from off Freetown, Sierra Leone, Millard (1975, 310, fig. 100E, as Sertularia turbinata forma acuta) from South Africa, and Hirohito (1995:217, figs. 73e, f, as Sertularia turbinata ) from Sagami Bay, Japan. Colonies examined here were sterile.

Detailed taxonomic and nomenclatural accounts of this species include those of Calder (1990 [1991a]) and Medel & Vervoort (1998, as Sertularia turbinata ).

Reported distribution. Gulf coast of Florida. Dry Tortugas: Loggerhead Key, on algae ( Leloup 1935a: 51, as Sertularia turbinata ; Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).—Dry Tortugas: S of Loggerhead Key ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).

Elsewhere in western North Atlantic. Bahamas: between Eleuthera and Little Cat islands + near Spanish Wells ( Nutting 1904: 60, as Sertularia brevicyathus ).— Bermuda: various locations, abundant, on sponges, seaweeds, large hydroids ( Congdon 1907: 481, as Sertularia brevicyathus ).— USA: Louisiana, occasional, on gulfweed ( Cary & Spaulding 1909: 6, as Sertularia brevicyanthus (sic)).— Bermuda: Challenger Bank, 31–70 ftm (57–128 m), on a gorgonian and algae + Agar’s Island, on Sargassum ( Bennitt 1922: 250, as Sertularia brevicyathus ).— Bonaire: Lac, mouth, back of reef, on detached Sargassum + Boca Washikemba, on stranded algae + Lagoen, north coast, on stranded Sargassum (Leloup 1935: 51, as Sertularia turbinata ).— Aruba: Boca Prins, on stranded Sargassum (Leloup 1935: 51, as Sertularia turbinata ).— Bahamas: Cay Sal Bank, 5–7 ftm (9–13 m), on benthic algae ( Leloup 1937: 106, as Sertularia turbinata ).—Atlantic Ocean: Gulf Stream, on pelagic Sargassum + Sargasso Sea, on pelagic Sargassum (Burkenroad, in Parr 1939: 23, as Sertularia brevicyathus ).— Puerto Rico: northeast coast, 18°27’35”N, 65°33’35”W, 26 ftm (48 m) + 18°24’30”N, 65°38’30”W, 9 ftm (16 m) + 18°23’35”N, 65°37’10”W, 10 ftm (18 m) ( Fraser 1944: 291, as Sertularia turbinata ).— Panama: Caledonia Bay (Puerto Escoces), on floating Sargassum ( Fraser 1947b: 11, as Sertularia turbinata ).— Venezuela: off Isla Tortuga, 2–5 ftm (4–9 m) ( Fraser 1947b: 11, as Sertularia turbinata ).— Colombia: La Goajira, Rio Hacha (=Riohacha), on algae ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Aruba: Boca Prins, on Sargassum + wharf of Arend Petroleum Co., on iron beam ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Bonaire: Oranjepan, on stranded Sargassum + Boca Washikemba, on stranded brown algae + Playa Grandi, on Sargassum ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Tobago: Rockley Bay (=Rockly Bay) on Sargassum ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).—West Indies: between Trinidad and Grenada ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Antigua: Deep Bay, at Fort Barrington, on algae, sponge ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Sint Maarten: Simson Lagoon, bridge, on algae ( Van Gemerden-Hoogeveen 1965: 38, as Sertularia turbinata ).— Virgin Islands of the United States: St. Thomas, Sound, on other hydroids ( Vervoort 1968: 52, as Sertularia turbinata ).— Colombia: off Santa Marta ( Wedler 1975: 340, as Sertularia turbinata ).— USA: Florida, southeast coast ( Mergner 1977: 122, as Sertularia turbinata ; 1987: 187, as Sertularia turbinata ).— Belize: Carrie Bow Cay, 0–10 m, on dead corals, gorgonians ( Spracklin 1982: 246, as Sertularia turbinata ).— Colombia: vicinity of Bahía de Cartagena ( Flórez González 1983: 120, as Sertularia turbinata ).— Bermuda: inshore, shallow waters + offshore, on banks, buoy chains ( Calder 1986: 139, as Sertularia turbinata ).— USA: Louisiana, on a coastal petroleum platform, 46 m ( Lewbel et al. 1987: 214, as Sertularia turbinata ).— Belize: Twin Cays ( Ellison & Farnsworth 1990: 96, as Sertularia turbinata ).— Bermuda: Whalebone Bay, 1 m, on ledge + Flatts Inlet, on rocks, Thyroscyphus marginatus , 2 m (Calder 1990 [1991a]: 111).— Belize: Twin Cays, on Rhizophora , benthic algae, sponges, other invertebrates ( Calder 1991b: 223; 1991c: 2068).— Belize: Lark Cay, on Rhizophora +Northeast Cay, on Rhizophora + Twin Cays, on Rhizophora ( Ellison & Farnsworth 1992: 90, as Sertularia turbinata ).— Bermuda: Walsingham Pond ( Thomas et al. 1992: 139, 152, as Sertularia turbinata ).— Bermuda: Harrington Sound, just below tidal level ( Thomas 1996: 758, as Sertularia turbinata ).— USA: North Carolina, off Cape Lookout in Gulf Stream, 34°10’N, 76°13’W, on Sargassum ( Stachowicz & Lindquist 1997: 116) .— Bermuda: Argus (=Plantagenet) Bank, on Argus Tower, 20 m ( Calder 2000: 1135, 1136).— Panama: Bocas del Toro area, Boca del Drago, 09°25’36.3”N, 82°19’30.1”W, 1-3 m + Bocas del Toro area, Cayos Zapotilla, 09°15.564’N, 82°02.750’W, 7-8 m + Bocas del Toro area, Swan’s Key, 09°27’12.2”N, 82°18’01.8”W, 1-4 m + Bocas del Toro area, Drago 2, mangrove, 1–2 m + Bocas del Toro area, Drago 2, 2– 4 m ( Calder & Kirkendale 2005: 486).—French Lesser Antilles: Guade- loupe, Basse-Terre, N of Malendure, 16°10’25.00”N, 61°46’58.00”W, on algae ( Galea 2008: 37, as Sertularia turbinata ).—French Lesser Antilles: Les Saintes, Terre-de-Haut, Pain de Sucre, 15°51’45”N, 61°35’60”W, on Dictyota , Thyroscyphus ramosus ( Galea 2008: 37, as Sertularia turbinata ).— USA: Florida: Fort Pierce Inlet, 27°28’24.1”N, 80°17’21.2”W, north jetty, intertidal, on benthic algae ( Calder 2013: 33).—French Lesser Antilles: Martinique ( Galea 2013: 50, as Sertularia turbinata ).—French Lesser Antilles: Martinique, Le François, Pointe Jacob, 14.58552, - 60.84993, 0 m, on floating Sargassum ( Galea & Ferry 2015: 235, as Sertularia turbinata ).—Caribbean Sea ( Wedler 2017b: 134, figs. 141A, B, 142, 143, as Sertularia turbinata ).— Mexico: Alacranes Reef, on shipwreck (Mendoza- Becerril et al. 2018b: 130, as Sertularia turbinata ).

Figures

FIGURE 21. a, Amphisbetia distans: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4387. Scale equals 0.1 mm. b, Amphisbetia distans: gonotheca, Sanibel Island, ROMIZ B4386. Scale equals 0.1 mm. c, Dynamena disticha: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4410. Scale equals 0.1 mm. d, Dynamena pourtalesi: part of hydrocaulus with two hydrothecal pairs, Southwest Florida Shelf, ROMIZ B306. Scale equals 0.2 mm. e, Idiellana pristis: base of hydrocaulus with a branch, Sanibel Island, ROMIZ B4390. Scale equals 0.2 mm. f, Idiellana pristis: part of branch with hydrothecae, Sanibel Island, ROMIZ B4390. Scale equals 0.1 mm. g, Tridentata turbinata: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4393. Scale equals 0.2 mm. h, Sertularella areyi: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B1978. Scale equals 0.2 mm. i, Sertularella diaphana: part of colony with three hydrothecae, Southwest Florida Shelf, ROMIZ B4392. Scale equals 0.2 mm. j, Sertularella unituba: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B2001. Scale equals 0.2 mm.