CLASSIFICATION OF ECHINOCARDIUM
KINGDOM :- ANIMALIA (Multicellular eukaryotic organisms)
PHYLUM :- ECHINODERMATA (Coelomate, pentaradiate and spiny skinned animals with vascular system.)
SUB-PHYLUM :- ELEUTHEROZOA (Non-pedicellate and free-living.)
CLASS :-ECHINOIDEA (Body oval or spherical and composed of test)
SUB-CLASS :- IRREGULARIA (Periproct displaced towards mouth in innerradius.)
GENUS :- Echinocardium (The heart urchin)
Cosmopolitan :- It has world-wide distribution.
HABIT AND HABITAT
Echinocardium burrows in sand 10 to 15 cm deep and moves by spines. It lives in a small chamber, which opens to surface by a chimney, through which animal feeds by protruding tube feet.
GENERAL CHARACTERSTICS OF ECHINOCARDIUM
- It shows extreme modification of echinoderm pattern as it becomes heart-shaped and is popularly known as heart urchin.
- Test is large in size with four well-developed petaloids and aboral surface and anterior anJ posterior sides.
- On oral surface long tubercles or long interambulacral spines are present.
- Apical central plate contains gonopores.
- Peristome or mouth becomes transversely extended.
- Aristotle’s lantern is absent.
- Ambulacral areas bear short tube feet and short spines called ambulacral spines.
- Inter-ambulacral areas bear long spines.
- Development includes echinopluteus larva.
The animal contains 4-well developed petaloid and all above features, hence, it is Echinocardium.