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.
References in periodicals archive ?
Additionally, sponge, hydroid, and bryozoan larvae attacked and rejected by fish settled and metamorphosed at rates statistically indistinguishable from unattacked controls [ILLUSTRATION FOR FIGURES 1B, 2B, 6B, AND 7B OMITTED].
While sight, sound and smell can be useful in separating family from strangers, a brain is definitely not necessary, according to Yale biologist Leo Buss, who has studied kin recognition in tiny and definitely brainless marine invertebrates called hydroids. These tentacle-bearing creatures, each the size of the head of a pin, colonize seashore boulders, kelp, boat hulls, dock pilings and the backs of marine snails.
(a) Hedgehog hydroid (Schuchertinia milleri) from Long Point, Palos Verdes Peninsula.
The animals were kept in fresh flowing seawater with their hydroid food, Eudendrium ramosum, for 1-60 days before study.
Some species identified as causing similarity within fishing grounds such as Alcyonium digitatum, hydroids, Ascidiacea, and Diodora graeca are known to be associated or occur as epibionts on queen scallops in the Isle of Man (Bradshaw et al.
Hydroids and hydromedusae (Cnidaria: Hydrozoa) from the fjords region of southern Chile.
Norwegian high-tech group Kongsberg Gruppen ASA (OSE: KOG) said on Monday (16 June) that its business area Kongsberg Maritime has completed its acquisition of the US company Hydroid LLC.
Gross vertical zonation patterns within the epifaunal communities consist of shallow assemblages (i.e., [less than] 3 m depth) dominated by mussels, barnacles, and algae; assemblages at intermediate-depths (i.e., 3-6 m) dominated by bryozoans, hydroids, and mussels; and deeper (i.e., [greater than] 6 m) assemblages, composed of sponges, bryozoans, brachiopods, cnidarians, and ascidians (Grange et al.
Natural selection on hydroid colony morphology by intraspecific competition.
With the exception of three species of algae (Enteromorpha flexuosa, Ceramium nitens, and Wrangelia argus), one hydroid (Dynamena crisioides), and three sponges (Haliclona curacaoensis, Spirastrella sp., and Tedania ignis), species that were either frequent or dominant at a given site were not necessarily so at other sites.
Notes on the distribution, ecology, and morphology of the colonial hydroid Cordylophora caspia (Pallas) in southern Louisiana.