In the beach sand and soft mud of Talsari and Digha Mohana, there are inhabited by several kinds of marine worms. They are plot worms (Platyhelminthes); round worms (Nematodes); ribbon worm (Nemartians) and segmented worms (Polychaetes – Annelida).
Extensive study of these worms from Digha beach yet to be done. Among these only polychaetis are quite described from this area. A total 34 species of Polychactes are known from Digha and adjoiningarea, of which some common species are briefly described here.
POLYCHAETES –
Polychactes are typically marine worms have a slender and segmented body. Each segment, bears a pair of bunches of setae or fleshy paddle like appendages called parapodia. The head region is well developed, bears a pair of eyes, antennae and palps. Mouth is situated at the ventral side in anterior segment. These worms are very colourfull and occupe all types of habitat in this sea shore (Along the intertidal sandy beach, mudflats, wooden pools, below the boulders, as parasite of crabs and moluscs).
Among the 34 species only 5 common species are shortly described. The 5 species are
1. Diopatra Cuprea
2. Eteone barantollae
3. Glycera Cenvoluta
4. Loimia medusa
5. Chlocia Purva
C. 1.
Diopatra Cuprea
Tentacular cirri present, branchial filaments arranged in where Prostomium with a short frontal antennae. A pair of palps and 5 occipital antennae Anterior parapodia well developed with long, triangular dorsal and ventral cirri. Colour scarlet with pulsating tree like plumed red gills. Length 10-15 cm.
It is tube dwelling polychactes. Lives in tough tube, about 40-60 cm long, embed in stift sand. 3 to 5 cm of tubes projects and curls over the surface of substratum and are impregnated with shell fragments, leaves etc.
Habitat – Plenty occurs in between MWM and LWM. Often forming a dense bed in sheltered areas. Mostly prefer fine sand mixed with mud. At Talsari, a large colony found in the sand fit and mud flat.
C. 2)
Scientific name – Eteone barantollae Fauvel Diagnosis – Body yellowish to greenish. Prostomium oval, as long as wide, with two pair of short antennae. Pharynx with 5 rows of distal swollen papillae, mid dorsal rows of distal swollen papillae, mid dorsal rows boarder than lateral one’s. Size 5 to 7 cm long.
Habitat – Lives in mud impregnated fine sand in the sandy zone between MTW to LWM during low tide, it is common sight to crawling of this species on beach surface. It is on endemic species in east coast of India
C. 3).
Glycera Convoluta Keferstein
Diagnosis – It is Hesh coloured specimen prostomium with 10-12 rings. 2 small eyes and 4 small tentacles distally, pharyngeal papillae of 2 kinds, mostly eylindrical with cape like sheath and distal mammillae tip and others rounded. Parapodia with two long, cirri form and acicular ligules and a short rounded postketallabes.
Habitat – Most common polychaetes of this beach, found in most area (HWm to LWM) of sandy beach, below 10-15 cm from sand surface. Maximum population found in Donax bed at HWM
C. 4.
Scientific Name – Loimia medusa (Savigny) Diagnosis – Prostomium reduced; tentacular tobes short, collar like with long tentacles on anteroventral surface. Buccal segments with a large foliaceoui lower lip. Branchiae 3 pairs on segments 2,3 and 4, with numerous filaments arranged dicho to mosuly, colour fleshy with greenish tentacles.
Habitat – Adults in rigid ‘U’ shaped tubes created with sand with multiple openings forming ……. In sheltered areas ……… ……..
C. 5
Scientific name – Chlocia purva Baird Diagnosis – Dark marhs in the form of Roman amanged in arow along middle of the dorsum. It is brown coloured specimen, differ in forms and shape from other polychaetes of this bench 56 cm long and 1 to 1.5 cm wide. Britles are create irritation in handling the specimen
Habitat – Mostly caught by dragnet. Juveniles are found in prawn seed collector’s net.
