CLASSIFICATION OF PROTODRILUS
PHYLUM :- ANNELIDA (Metamerically segmented, coelomate and laterally symmetrical. )
CLASS :- ARCHIANNELIDA (Primitive annelids.)
ORDER :- HAPLODRILI (Primitive polychaete worms)
FAMILY :- POLYGORDIIDAE (Short tentacles.)
GENUS :- Polygordius
SPECIES :- lacteus
It is found living in tht, sand of the European seas
HABIT AND HABITAT
Polygordius is a small, simple, aberrant, marine scavenger worm
GENERAL CHARACTERSTICS OF POLYGORDIUS
- Body is narrow, elongated, cylindrical and resembles larval polychaetes.
- Divisible into head and body segments, measuring 30 to 100 mm.
- Head comprises of small prostomium and large peristomium.
- Head bears a pair of small prostomial tentacles, ventral mouth and ciliated pits.
- External segmentation of the body is faintly marked by grooves in anterior region and clearly marked in posterior region.
- Coelom is divided by septa, last segment contains anus.
- Setae, parapodia, cirri and gills are absent.
- Sexes are separate. Gonads develop in posterior segments. There are no reproductive ducts.
The animal contains small prostomium and large peristomium and all above features, hence it is Polygordius.