CLASSIFICATION OF SEA CUCUMBER OR CUCUMARIA
PHYLUM :- ECHINODERMATA (Coelomate, pentaradiate and spiny skinned animals with vascular system.)
SUB-PHYLUM :- ELEUTHEROZOA (Non-pedicellate and free-living.)
CLASS :- HOLOTHUROIDEA (Body orally and aborally elongated.)
ORDER :- DENDROCHIROTA (Oral tentacles tree-like – dendroid.)
GENUS :- Cucumaria (The sea cucumber)
It has cosmopolitan distribution and specially found in Europe, U.S.A. and India.
HABIT AND HABITAT
Cucumaria is inhabits approximately 200 fathoms deep wholly or partially buried in the mud. It feeds on detritus and plankton.
GENERAL CHARACTERSTICS OF SEA CUCUMBER OR CUCUMARIA
- Commonly called as sea cucumber.
- Body is elongated horizontally along the oral aboral axis. Colour of the body may be whitish, reddish or brown.
- Oral end contains a whorl of 10 dendritic bushy, pinnately branched tentacles surrounding the terminal month. Tentacles are modified tube feet.
- Anterior region is called as collar which contains mouth at anterior extremity.
- Rest of the body differentiated into 5 ambulacral and 5 inter ambulacral zones. Ambulacral grooves are covered and run longitudinally.
- Tube feet, when present, usually possess suckers and are either arranged in rows or are irregularly scattered.
- Body wall which is dermo-muscular contains very small separate ossicles.
- There is a single genital aperture, middorsally situated between the bases of two adjacent inter-ambulacral tentacles near mouth.
- Animal rests on the so-called ventral surface, which is flattened and paralleled with oral aboral axis of the body, and is pentaradiate. It has 3 ambulacral areas trivium and forms sole. Dorsal surface with 2 ambulacral areas is called as bivium. Anus is aboral with paired respiratory trees.
- Larva are Auricularia Doliolaria.
The animal contains whorl of pinnately branched tentacles and all above features, hence it is Cucumaria.