Tentaculata is a class of
comb jellies. The common feature of this class is a pair of long, feathery, contractile
tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...
s, which can be retracted into specialised
ciliated sheaths. In some species, the primary tentacles are reduced and they have smaller, secondary tentacles. The tentacles have
colloblasts, which are sticky-tipped cells that trap small prey.
Body size and shape varies widely. The group includes the small, oval
sea gooseberries found on both Atlantic and Pacific coasts. The more flattened species of the genus ''
Mnemiopsis'', about long, are common on the upper Atlantic coast; it has a large mouth and mainly feeds on larval
molluscs and
copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...
s. This species is brilliantly
luminescent. The similar, but larger, genus ''
Leucothea'' is abundant on the Pacific coast.
Venus girdle
The Venus girdle (''Cestum veneris'') is a comb jelly in the family Cestidae. It is the only member of its genus, ''Cestum''.
Description
Venus girdles resemble transparent ribbons with iridescent edges. They may grow up to a metre in total len ...
(genus ''Cestum'') is a flattened, ribbon-like form reaching over in length, and found in tropical waters.
References
Barnes, R.S.K. et al. (21 September 2001). ''The Invertebrates: A Synthesis''. Oxford: Blackwell Science.
Animal classes
{{Ctenophore-stub