CLASSIFICATION OF APHRODITA
PHYLUM :- ANNELIDA (Metamerically segmented, coelomate and laterally symmetrical. )
CLASS :- POLYCHAETA (Many setae, clitellum absent. )
ORDER :- ERRANTIA (Free-swimming or burrowing, pharynx protrusible, provided with jaws and teeth. )
GENUS :- Aphrodita
- It is found in U.S.A.
HABIT AND HABITAT
Aphrodita is marine worm inhabiting the deep water muddy bottoms
GENERAL CHARACTERSTICS OF APHRODITA
- Commonly called as sea mouse measuring approximately 12 cm in length and made up of 30 to 35 segments.
- Body is covered dorsally by felt-like or blanket-like setae arising from the notopodium.
- Shape of the animal is oval, and dorsoventrally flattened. The dorsal surface is convex and is covered with setae of different kinds.
- Anterior end contains a small head or prostomium, bearing a small median tentacle and 2 lateral palps. Anus is dorsally situated at the more pointed posterior extremity.
- Parapodial structures are greatly modified. Notopodia contain 3 kinds of setae-(i) stiff setae, (ii) soft setae, and (iii) iridescent setae.
- Neuropodial setae are also brown and stiff. The soft notopodial setae are modified to form a felt-like covering over the back of the animal, while dorsal cirri become plate-like and are called as elytra, 15 pairs in number. The elytra obtain dissolved oxygen from the sea water circulating around them.
- Ventral surface is flat, segmented and forming a creeping sole. Each ventral segment or metamere contains stiff setae. (8) Pumping action of the dorsal body wall causes the sea water to be filtered through the dorsal felt into the space below
Animal rolls itself with erect stiff setae like porcupine to protect itself from enemies when disturbed. During movement of the animal, colour changes from gold to peacock.
The animal contains distinct stiff setae, iridescent setae and all above characters hence it is Aphrodite.