CLASSIFICATION OF CHAETOPTERUS ( PADDLE WORM )
PHYLUM :- ANNELIDA (Metamerically segmented, coelomate and laterally symmetrical. )
CLASS :- POLYCHAETA (Many setae, clitellum absent. )
ORDER :- TUBICOLA (Tubicolous, sedentary and proboscis non-protrusible, without jaws or teeth.)
GENUS :- Chaetopterus (The paddle worm)
It is commonly found in Europe, U.S.A., North Carolina to Cape Cod.
HABIT AND HABITAT
Chaetopterus is a tubicolous, marine and bioluminescent annelid which lives permanently in a U-tube, made of sand and mucus with incurrent and excurrent openings. The tube is parchment like. Mode of feeding is ciliary.
GENERAL CHARACTERSTICS OF CHAETOPTERUS ( PADDLE WORM )
- Commonly called as paddel worm having greatly modified segments.
- Tube is opaque, measuring approximately 50 cm long and about 1 cm in diameter.
- Body is white, delicate, 30 cm long and divided into anterior, middle and posterior regions. The tentacles and palps are absent except a pair of backwardly directed peristomial cirri.
- Parapodia are variously modified as for water pumping fans, sucking discs or food ball organs.
- Anterior region comprises of 15 to 20 segments, having a funnel-shaped mouth surrounded by a collar-like peristomium and a pair of peristomial cirri in the first segment. Rest of the segments have reduced notopodium. Tenth segment bears great aliform wings like notopodia which collect food.
- Middle region has fused segments. The notopodia of segments 14 to 16 are fused in mid line to form three fans. Notopodia are fused to form suckers.
- Posterior region is longer with a pair of parapodia in each segment, about 11 to 30 in number.
- The worm is strongly luminescent producing bluish-green light without heat. The light is produced by the action of luciferins and luciferase. Other special feature of the worm is its power of regeneration. The whole body can be regenerated from a single segment.
- The animal has greatly modified segments and all above features, hence it is Chaetopterus.