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 ?
Amiloride appeared to be weakly inductive to larvae of the hydroid Hydractinia echinata: a 600 [micro]mol [l.
Studies on southwestern Atlantic intertidal hydroid communities are rare, but include distributional inferences for the Brazilian tropical-subtropical coast (Rosso & Marques, 1997), and ecological assessments of seasonal richness, abundance, zonation and substrata for southern temperate waters (Genzano, 1994; Genzano & Rodriguez, 1998).
Doto form A is the most common Doto in the southern California bight and is commonly observed subtidally on campanularid hydroids growing on kelp and other macroalgae.
Clearly, the hydroid habitat offers a form of shelter and protection from abrasion and grazers.
Kongsberg's REMUS family of AUVs built by its subsidiary Hydroid can also perform visual pipeline inspections and pipeline surveys when equipped with high-frequency sidescan sonar, a multi-beam and camera.
The Norwegian company entered the contract via its subsidiary Hydroid Inc, USA.
The bottle brush hydroid occurs in these chalk reefs.
In January 2002, various species of algae, sponge, hydroid and tunicate colonies were scraped from the south jetty during an extremely low tide.
In the summer and fall, the shallow, well-lit portion of the jetty is dominated by brown seaweeds like Sargassum, Padina, and Dictyota, whereas the deeper portions are dominated by colonial invertebrates, including the scleractinian coral Oculina arbuscula, the upright bryozoan Bugula neritina, the hydroid Eudendrium carneum, several species of tunicates, and a few sponges.
Katrina was searching the tidepools for a hydroid that she had discovered several years ago: Samuraia tabuarasa.
Evolutionary genetics of allorecognition in the colonial hydroid Hydractinia symbiolongicarpus.
This dichotomy between the palatability of larval and adult extracts was not apparent for the hydroid Eudendrium or the sponges Calyx or Ectyoplasia, for which extracts from both adults and larvae strongly deterred feeding (P [less than] 0.