Benthic hydroids (Cnidaria, Hydrozoa) from bathyal and abyssal depths of the Northeast Atlantic held in the modern Discovery Collections Author Peña Cantero, Álvaro L. Author Horton, Tammy text Zootaxa 2017 2017-11-10 4347 1 1 30 journal article 31577 10.11646/zootaxa.4347.1.1 49a11228-6c4d-478f-b958-52610eaab951 1175-5326 1044772 176D72B0-0DD6-4D51-83CA-D47C2268A3CF Modeeria rotunda ( Quoy & Gaimard, 1827 ) ( Fig. 4A–B ) Modeeria rotunda — Vervoort & Watson, 2003 : 31 –32 (synonymy). Material examined. 51217#1 , several hydrothecae, on Sertularella gayi , no gonothecae. Description. Stolonal colonies, a filiform hydrorhiza giving rise to small hydrothecae on short pedicels ( Fig. 4A ). Hydrotheca tubiform, with basal circular diaphragm ( Fig. 4B ). Hydrothecal rim uneven, with two large cusps, separated by two large embayments ( Fig. 4A ). Operculum composed of two semi-circular, pleated valves, attached to rim embayments and closing as a roof. Measurements (in µm). Hydrotheca : diameter at aperture 220–230; height, up to diaphragm 730–800, diameter at diaphragm 80–100, length of pedicel 100. Ecology and distribution. Eurybathic species, found at depths from 0.5 ( García Carrascosa 1981 ) to 1214 m (Schuchert 2001); the present material was collected from the Porcupine Seabight at 150 m , on Sertularella gayi . Circumglobal from boreal to tropical waters ( Vervoort & Watson 2003 ).