Some shallow-water hydroids (Cnidaria: Hydrozoa) from the central east coast of Florida, USA Author Calder, Dale R. text Zootaxa 2013 2013-05-14 3648 1 1 72 http://dx.doi.org/10.11646/zootaxa.3648.1.1 journal article 10.11646/zootaxa.3648.1.1 1175-5326 5264362 22089255-436A-4DBB-BD93-1D3C8CF281FE Dynamena disticha ( Bosc, 1802 ) Fig. 8d Sertularia disticha Bosc, 1802: 101 , pl. 29, fig. 2. Type locality. Atlantic Ocean: “...sur le fucus natans ...” ( Sargassum natans ) ( Bosc 1802 ). Voucher material. Fort Pierce , Fort Pierce Inlet State Park , 27°28’29.5”N , 80°17’25.8”W , on stranded Sargassum sp. , 14.vii.2012 , 28° C, 35‰, collected manually, one colony, 4 mm high, without gonophores, coll. D.R. Calder , ROMIZ B3966 . Remarks. Hydroids referred to Dynamena disticha ( Bosc, 1802 ) in the western Atlantic occur in two forms, a stunted one (< 1 cm high) found on floating Sargassum and a much larger one (up to 5 cm high) on a variety of benthic substrates. It remains to be confirmed whether they are actually conspecific. Specimens observed here, growing on a species of Sargassum , were of the stunted variety as originally described by Bosc (1802) . Comments on the taxonomy of this species have been given earlier ( Calder 1991a ). Included in the synonymy of D. disticha therein were the following, all originally described from the western North Atlantic: Sertularia exigua Allman, 1877 , S. distans Allman, 1877 , S. complexa Clarke, 1879 , Dynamena bilatteralis Brooks, 1883 , Sertularia mayeri Nutting, 1904 , S. pourtalesi Nutting, 1904 , and with question Dynamena cornicina McCrady, 1859 . An extensive list of literature on D. disticha was given in Medel & Vervoort (1998) . Reported distribution. Atlantic coast of Florida . First record. Western Atlantic. Massachusetts ( Nutting 1901 , as Sertularia cornicina and S. complexa ) to Argentina (Oliveira et al . submitted), including Bermuda ( Calder 1991a ), the Gulf of Mexico ( Calder & Cairns 2009 ), and the Caribbean Sea ( Calder & Kirkendale 2005 ; Galea 2008 ). The species has been reported on Sargassum in the Gulf Stream as far north as Nova Scotia ( Fraser 1918 , as S. cornicina ). Elsewhere. Circumglobal in tropical, subtropical and temperate waters ( Peña Cantero & García Carrascosa 2002 ).