hydroid

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hydroid

a member of the COELENTERATE class Hydrozoa. Most are colonial forms which grow in the marine environment on rocks and seaweeds, such as Obelia. Usually, there is an ALTERNATION OF GENERATIONS (not in HYDRA) in which the MEDUSA (free-swimming) stage carries the sex organs. The sedentary, nonsexual stage of this life cycle is itself referred to as the POLYP or (less commonly) hydroid stage.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Fringe bottom is predominantly formed by sand and gravel sediments, but salt marshes and rocky outcrops are also frequent (Bastida et al., 2007; Bortolus et al., 2009), providing colonizable areas for hydroids. However, the lack of studies on the hydroid fauna distributed along ~2,000 km of the Patagonian coast represents a substantial gap in our biodiversity knowledge.
Increased weight and drag could also make the host more likely to be dislodged from the hydroids on which it lives.
Juvenile red king crab and blue king crab (Paralithodes platypus) prefer highly structured habitats, which consist of pebbles, cobble, hydroids, macroalgae, shell material, etc., where they are less vulnerable to predators (Stoner, 2009; Pirtle and Stoner, 2010).
Briggs EA (1931) Notes on Australian athecate hydroids. Records of the Australian Museum 18, 279-282.
This makes it quite similar with other defenseless creatures of the ocean waters like hydroids and jellies.
femoratum were collected from Kandalaksha Bay of the White Sea along with a colony of hydroids, Ectopleura larynx (Ellis & Solander, 1786), on which they were living and feeding.
Beyond the rampart, the reef slopes into sublittoral fore-reef and back-reef zones featuring hard corals, soft corals, hydroids, bryozoans and macroalgae, such as Sargassum.
To enumerate the abundant/encrusting species, including sponges, hydroids and algae, frame grabs were extracted at 5 s intervals and overlaid with a digital quadrat (3Dive Frame Extractor Software).
Hydroids of the Allan Hancock Pacific Expeditions since March, 1938.
Randall (1985) wrote of the extremely varied diet: algae (including Jania and Halimeda), bivalves, gastropods, tunicates, sponges, corals, zoanthid anemones, crabs, tube worms, sea urchins, brittle stars, starfishes (including Acanthaster), hermit crabs, hydroids and detritus.
Many are covered with tough, stringy hydroids and icky little shrimpy things that my running buddy, WHOI biologist Stace Beaulieu, later tells me are amphipods when I quiz her with pictures.