Jellyfish" often refers to the gelatinous cousins of corals in Cnidaria
Sketch the Obelia Cnidaria
set) medusa (pelagic form) Obelia Medusae slide and label the bell, Deerhorn coral skeleton mouth, and tentacles.
Strictly defined as stinging animals of the phylum Cnidaria
, the title now colloquially encompasses most gelatinous creatures of the sea, a wide range of 'Jellyfish-like organisms.
Part of the phylum Cnidaria
(nigh-DARE-ee), jellyfish are very simple creatures.
Most recently, Sphenothallus has been assigned to the large group of animals called Cnidaria
, which includes corals, jellyfish, hydra, and a host of other primitive organisms, most of which live in the sea.
The taxonomic classification of the 68 most common invertebrate species is as follows: Mollusca (N = 27), Arthropoda (N = 22), Echinodermata (N = 6), Porifera (N = 5), Annelida (N = 4), and Cnidaria
(N = 4).
In fact, corals are related to jellyfish and sea anemones and belong to the same phylum--the Cnidaria
Biodiversity of species resides probably more in tropical rain forests and cloud forests than any other habitat, whereas diversity of phyla (echinoderms, chordates, cnidaria
, mollusks, ctenophores) is greatest on the coral reef.
Although screening studies of antibacterial activity in marine invertebrate phyla (Porifera, Cnidaria
, Echinodermata, Mollusca) have shown that Gram-positive bacteria are more sensitive than Gram-negative strains to extracts or tissues from marine organisms (Haug 2004), several studies have demonstrated that bivalve hemolymph lyses both Gram-positive and Gram-negative bacteria (Chu 1988, Cheng 1983).
The discovery of this new order of Cnidaria
-- a phylum that includes jellyfish, corals, sea anemones, and their relatives -- is the equivalent to finding the first member of a group like primates or rodents," said EstefanEaA[degrees]a RodrEaA[degrees]guez, an assistant curator in the Museum's Division of Invertebrate Zoology and the lead author of the new publication.
This specimen from the Arctic is probably a new species of comb jelly, (Unlike true jellyfish, in the phylum Cnidaria
, comb jellies don't have stinging cells.
Corals belong to a large group of relatively simple and colorful organisms called Cnidaria
ANIMALIA 1,320,000 MESOZOA METAZOA 1,320,000 Porifera (sponges) 10,000 Cnidaria
(hydras, jellyfish, corals, etc) 10,000 Platyhelminthes (flatworms) 20,000 Nematoda (roundworms) 25,000 Echinodermata (sea uchins, etc.