CLASSIFICATION OF AMPHITRITE
PHYLUM :- ANNELIDA (Metamerically segmented, coelomate and laterally symmetrical. )
CLASS :- POLYCHAETA (Many setae, clitellum absent. )
ORDER :- SEDENTARIA (Tubicolous, sedentary and proboscis not-protrusible, without jaws or teeth.)
GENUS :- Amphitrite
It is found in Europe and U.S.A. (North Carolina to Cape Cod).
HABIT AND HABITAT
Amphitrite is a marine, sedentary polychaete, very common along the eastern coast of the United States. The animal dwells near the low tide level in tubes lined with mucus and buried in sand or mud.
GENERAL CHARACTERSTICS OF AMPHITRITE
- Animal is long cylindrical, and pinkish in colour measuring 20 to 30 cm in length
- Body is divided into metameres and regionated into somewhat thickened anterior region (head), middle region (trunk) and posterior narrow region.
- Prostomium forms the upper lip and peristomium lower lip of the mouth. No eyes and palps in prostomium. Peristomium is also without appendages. Prostomium forms proboscis.
- Just behind the head is a transverse ridge crowned with several, long hollow, yellowish and contractile tentacles having coelomic extension. They are feeding organs and have poor vascularization having a ciliated groove on one side.
- Branchial region consists of many segments bearing notopodia with setae and neuropodia with uncini. The first three segments of the middle region contain three pairs of bushy gills placed dorso-laterally.
- Gills contract rhythmically. Ventrally few thoracic segments have shield glands or ventral glands for mucus secretion.
- Abdomen is long and each segment contains notopodia and neuropodia (uncini).
- Caudal segments lack notopodia and anus is found terminally in the last segment as elongated aperture.
Generally Lepidometria a symbiont lives in the same tube with Amphitrite.
The animal contains anterior feathery tentacles and all above characters and hence it is Amphitrite.