Cnidarians

Cnidarians (IPA: /nɪˈdɛəriənz, knaɪˈdɛəriənz/), also called coelenterate, any member of the phylum Cnidaria (Coelenterata), a group mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.

List of Real-life Cnidarians

Box Jellies (Cubozoa)

The box jellyfish are cnidarian invertebrates distinguished by their box-like body. Some species of box jellyfish produce potent venom delivered by contact with their tentacles in class Cubozoa.


Hydras (Hydrozoa)

The hydra or Hydrozoa is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized individual animals cannot survive outside the colony.


Jellyfishes (Scyphozoa)

The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish. The class name Scyphozoa comes from the Greek word skyphos, denoting a kind of drinking cup and alluding to the cup shape of the organism. Scyphozoans have existed from the earliest Cambrian to the present.


Sturgeon Jellies (Polypodiozoa)

The Polypodium is a genus of cnidarians that parasitizes in the eggs of sturgeon and similar fishes. It is one of the few metazoans that live inside the cells of other animals. Polypodium hydriforme is the only species of this monotypic genus. The parent family, order and class are also monotypic.


Stalked Jellyfishes (Staurozoa)

The Staurozoa is a class of Medusozoa, jellyfishes and hydrozoans. It has one extant order: Stauromedusae with a total of 50 known species. A fossil group called Conulariida has been proposed as a second order, although this is highly speculative.


Myxozoa

The Myxozoa is a subphylum of aquatic cnidarian animals – all obligate parasites. It contains the smallest animals ever known to have lived. Over 2,180 species have been described and some estimates have suggested at least 30,000 undiscovered species.


Blue Corals, Soft Corals, Sea pens, and Gorgonians (Octocorallia)

Octocorallia is a class of Anthozoa comprising around 3,000 species of water-based organisms formed of colonial polyps with 8-fold symmetry. It includes the blue coral, soft corals, sea pens, and gorgonians within three orders: Alcyonacea, Helioporacea, and Pennatulacea.



Sea Anemones, Corallimorpharians, to Zoanthids (Hexacorallia)

The Hexacorallia is a class of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyps, generally with 6-fold symmetry. It includes all of the stony corals, most of which are colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant orders.


Tube-dwelling Anemones (Ceriantharia)

The tube-dwelling anemones or ceriantharians look very similar to sea anemones but belong to an entirely different class of anthozoans. They are solitary, living buried in soft sediments.


Foreign Languages

Box Jellies (Cubozoa)