hy·dro·zo·an

(hī′drə-zō′ən)

Any of various cnidarians of the class Hydrozoa, including the hydras, hydroids, and siphonophores, which exhibit alternation of generations between the polyp and medusa stage or exist in only one or the other stage.

[From New Latin Hydrozōa, class name : Hydra, type genus; see hydra + -zōa, pl. of -zōon, -zoon.]

hy′dro·zo′an adj.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

hydrozoan

(ˌhaɪdrəʊˈzəʊən)

(Animals) any colonial or solitary coelenterate of the class Hydrozoa, which includes the hydra, Portuguese man-of-war, and the sertularians

adj

(Animals) of, relating to, or belonging to the Hydrozoa

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

hy•dro•zo•an

(ˌhaɪ drəˈzoʊ ən)

n.

1. any freshwater or marine cnidarian of the classHydrozoa, including attached and free-swimming, often colonial, forms in which the medusa stage is reduced or lacking.

adj.

2. belonging or pertaining to the hydrozoans.

[1875–80; < New Latin Hydrozo(a) (see hydro-¹, -zoa) + -an¹]

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun

hydrozoan - colonial coelenterates having the polyp phase dominant

hydroid

cnidarian, coelenterate - radially symmetrical animals having saclike bodies with only one opening and tentacles with stinging structures; they occur in polyp and medusa forms

planula - the flat ciliated free-swimming larva of hydrozoan coelenterates

class Hydrozoa, Hydrozoa - coelenterates typically having alternation of generations; hydroid phase is usually colonial giving rise to the medusoid phase by budding: hydras and jellyfishes

hydra - small tubular solitary freshwater hydrozoan polyp

siphonophore - a floating or swimming oceanic colony of polyps often transparent or showily colored

sertularian - feathery colony of long-branched stems bearing stalkless paired polyps

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References in periodicals archive

One striking example of this concept was seen in research with the hydrozoan Hydra, where environmental and laboratory-reared organisms harbored the same microbiota (Fraune & Bosch 2007).

MICROBIAL ECOLOGY OF THE BIVALVIA, WITH AN EMPHASIS ON THE FAMILY OSTREIDAE

This corresponds to ~9% (26 of 295 species recorded) and less than 1% (26 of 3,428 species recorded) of the hydrozoan species recorded for the Argentinean Patagonia and worldwide, respectively (Oliveira et al, 2016; Schuchert, 2016), showing that the knowledge on the biodiversity of hydroids at intertidal habitats of Argentinean Patagonia is still scarce.

Faunal assemblages of intertidal hydroids (Hydrozoa, Cnidaria) from Argentinean Patagonia (Southwestern Atlantic Ocean)

As shown in Table 4, some of the classes such as hydrozoan, acorn barnacle, algae, finger sponge, and Christmas tree worm produced a result of less than 70%, which as mentioned above was set as the benchmark for what is acceptable.

Intelligent Image Recognition System for Marine Fouling Using Softmax Transfer Learning and Deep Convolutional Neural Networks

But this hydrozoan, common in the western Mediterranean and Adriatic seas, is something of a cheat.

Aging's wild side: escape artists and suicidal reproducers offer clues to how senescence evolved

Human nature, this time (as opposed to hydrozoan) about which I ponder a LOT.

THIS MUCH I KNOW

The specimens were identified as the crawling medusa, Eleutheria dichotoma, which is one of a small group of hydrozoan medusae that crawls on algae rather than swimming in the plankton.

First record of the crawling medusa Eleutheria dichotoma from Victoria

The endozoic association and its diminutive tetrasporic filaments likely represent an advantageous adaptation to low incident light, which is further reduced in quality and quantity by the hydrozoan exosarc cover.

The Boulder Patch (North Alaska, Beaufort Sea) and its benthic algal flora

"The discovery of green fluorescent protein in a hydrozoan jellyfish in the 1960s has provided a revolutionary tool for modern biologists, transforming our study of everything from the AIDS virus to the workings of the brain," Gruber said.

Rich World of Fish Biofluorescence Illiuminated

In the Red Sea, substrates are living corals like hydrozoan Millepora spp.

Detection of bioactive compounds in the mucus nets of Dendropoma maxima, Sowerby 1825 (Prosobranch Gastropod Vermetidae, Mollusca)

For example, throughout earth history, genuine scyphozoan, hydrozoan, or cubozoan medusae are only known from [less than or equal to] 10 deposits, all of which are significant or potential Konservatlagerstatten (Young and Hagadorn 2010).

Hypothesized Cambrian medusae from Saint John, New Brunswick, reinterpreted as sedimentary structures

The 4-5mm diameter creature, technically known as a hydrozoan, is the only known animal that is capable of reverting to its juvenile polyp state.

Meet the world's only immortal creature!