Fig. 8e, f
Sertularia quadridentata Ellis & Solander, 1786: 57, pl. 5, figs. g, G.
Dynamena quadridentata.— Jones, 2002: 218.
Type locality. South Atlantic Ocean, on algae “...not far from the island of Ascension ” (Ellis & Solander 1786).
Voucher material. Off Fort Pierce, 27°10.8’N, 80°02.5’W, 21.6 m, on benthic algae, 24.vii.1975, R/V Johnson and Johnson-Sea-Link, JSL 273, one colony, up to 6 mm high, with gonophores, coll. T. Askew, ROMIZ B1085.
Remarks. This hydroid has commonly been known as Dynamena quadridentata (Ellis & Solander, 1786) (synonymy in Vervoort & Watson 2003). However, molecular studies by Moura et al. (2011) indicate that the nominal genus Dynamena Lamouroux, 1812 is polyphyletic, and that D. quadridentata is genetically distant from D. pumila (Linnaeus, 1758), its type species. Pasya Stechow, 1922 (type species: Sertularia quadridentata Ellis & Solander, 1786), generally regarded as a synonym of Dynamena, is resurrected here for the species. The specific name quadridentata has also been combined in the past with Pasythea Lamouroux, 1812, but that nominal genus is now restricted to Bryozoa (type species: Cellaria tulipifera Ellis & Solander, 1786). Additional discussion of nomenclature relevant to these names has been given earlier (Calder 1991: 89).
Pasya quadridentata, common in the Caribbean Sea region (Vervoort 1968; Calder & Kirkendale 2005, as Dynamena quadridentata), ranges northwards to the Carolinas along the east coast of the United States (Cain 1972; Calder 1983, as D. quadridentata). The species is transported to even higher latitudes in the Gulf Stream on floating Sargassum (Fraser 1912b; Burkenroad, in Parr 1939, as Pasythea quadridentata), including New England (Hargitt 1908, as Pasythea nodosa).
Reported distribution. Atlantic coast of Florida. Biscayne Bay (Jones 2002, as Dynamena quadridentata).
Western Atlantic. Woods Hole region, Massachusetts (Hargitt 1908, as Pasythea nodosa) to Brazil (Oliveira et al. submitted, as D. quadridentata), including Bermuda (Calder, 1991a, as D. quadridentata), the Gulf of Mexico (Calder & Cairns 2009, as D. quadridentata), and the Caribbean Sea (Calder & Kirkendale 2005, as D. quadridentata).
Elsewhere. Circumglobal in temperate and tropical waters (Vervoort 1968; Vervoort & Watson 2003).