Hippothoa flagellum Manzoni, 1870
(Fig. 21; Table 20)
Material examined. VMNH. no. 70631, 70632; USNM no. 1283247.
Description. Colonies forming inconspicuous, thread-like uniserial chains of zooids that may branch or meander over unoccupied substrata between and among larger calcareous epifauna (Fig. 21 A). Autoozooids oval, convex, with broadly cleithridiate orifice surrounded by low, smooth-rimmed, slightly hooded peristome (Fig. 21 B, F). Autozooids with long trailing, stolon-like caudate portion connected with preceding zooid (Fig. 21 C). Autozooids with single distal budding site and paired lateral budding sites. Female zooids form at latter sites (Fig. 21 E, F), are smaller than autozooids, with a more pointed proximal end and a distal orifice that is shorter and wider than in autozooids. Ooecia helmet shaped and imperforate; orifice with broad proximal sinus
Remarks. The species is considered to be widespread on calcareous substrata in temperate and tropical waters. The Oculina specimens best fit the definition of this species, but zooidal dimensions are slightly smaller and the orifices of autozooids less elongate than those of Mediterranean specimens studied by Hayward & McKinney (2002).
Distribution. In the Western Atlantic it occurs from Cape Hatteras to Florida and the Caribbean.