Hydrozoa (hydrozoans; from Ancient Greek ὕδωρ (húdōr; "water") and ζώα (zóa; "animals")) is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water.

Hy­dro­zoans are found in nearly all ma­rine habi­tats, ex­cept per­haps heavy surf zones. They are most abun­dant and di­verse in warm shal­low wa­ters, prob­a­bly as a re­flec­tion of food abun­dance. The small num­ber of fresh­wa­ter species occur in both lotic and lentic habi­tats, and are more abun­dant in eu­trophic and mesotrophic wa­ters.

Oct 31, 2023 · Hydrozoa is a class of aquatic invertebrates that are closely related to corals, jellyfish, and sea anemones. They belong to the phylum Cnidaria, which also includes other gelatinous zooplankton like jellyfish and box jellies. Their …

Perhaps the best-known hydrozoan, familiar to most students of introductory biology, is Hydra, pictured at left. Hydra never goes through a medusoid stage and spends its entire life as a polyp . However, Hydra is not typical of the Hydrozoa as a whole.

The meaning of HYDROZOAN is any of a class (Hydrozoa) of cnidarians (such as the hydra, fire coral, and Portuguese man-of-war) that includes solitary and colonial polyps and medusae but often having the medusa stage reduced or absent and lacking nematocysts in the digestive cavity.

3 days ago · The World Hydrozoa Database includes all extant hydrozoan species and is intended to act as a tool for anyone looking for taxonomic information, both specialists and non-specialists alike.

hydroid, any member of the invertebrate class Hydrozoa (phylum Cnidaria). Most hydroids inhabit marine environments, but some have invaded freshwater habitats. Hydroids may be either solitary or colonial, and there are about 3,700 known species.

Hydrozoans include marine hydroids, freshwater hydras, some known as jellyfish and corals, and the well-known Portuguese man-of-war (or Portuguese man o' war). While the often small and diaphanous hydrozoa, as polpys or medusae, often go unnoticed, they are important in …

Hydrozoa (hydrozoans; from Ancient Greek ὕδωρ (húdōr) 'water', and ζῷον (zôion) 'animal') is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water.

Hydrozoa (Hydrozoans) is a class of cnidarians. There are 4058 species of Hydrozoans, in 590 genera and 134 families. They are carnivores. They have asexual reproduction and sexual reproduction. Capable of the biological process in which new individuals are produced by either a single cell or a group of cells, in the absence of any sexual process.