ON SOME POLYCHAETES FROM ANDAMAN AND NICOBAR ISLANDS

The polychaete fauna of the Andaman and Nicobar Islands is very rich in diversity as well as in abundance of species, because of numerous varied eco-niches available in the littoral and sublittoral zones of the coast. Our current knowledge of the polychaetes of these islands is based mainly on the works of Fauvel (1932, 1953) and Tampi and Rangarajan (1964), but it is far from complete. More intensive field collections are likely to yield rich dividends in knowledge and further additions to the faunal list, as 'will be evidenced from the present paper which reveals eight additional species from these islands, froln amongst a total of 26 species dealt with. The material for the present study was collected at various periods by different parties of the Zoological Survey of India. It comprises 26, species belonging to 20 genera and 13 families. Descriptions and variations have been furnished wherever 'necessary. Only relevant synonymies have been included since most of these have already been given by Fauvel (op. cit.), Tampi and Rangarajan (op. cit.) and Day (1951, 1953, 1957). .


INTRODUCTION
The polychaete fauna of the Andaman and Nicobar Islands is very rich in diversity as well as in abundance of species, because of numerous varied eco-niches available in the littoral and sublittoral zones of the coast.Our current knowledge of the polychaetes of these islands is based mainly on the works of Fauvel (1932,1953) and Tampi and Rangarajan (1964), but it is far from complete.More intensive field collections are likely to yield rich dividends in knowledge and further additions to the faunal list, as 'will be evidenced from the present paper which reveals eight additional species from these islands, froln amongst a total of 26 species dealt with.
The material for the present study was collected at various periods by different parties of the Zoological Survey of India.It comprises 26, species belonging to 20 genera and 13 families.Descriptions and variations have been furnished wherever 'necessary.Only relevant synonymies have been included since most of these have already been given by Fauvel (op.cit.), Tampi and Rangarajan (op. cit.) and Day (1951Day ( , 1953Day ( , 1957))    Description.-Prostoilliumsmall with a pair of tentacles and a pair of eyes.Caruncle heart-shaped with a small l11edian tentacle.Bushy gills orange .. coloured~ and beginning from 2nd setigerous segment.Dorsal setae capillary and some harpoon shaped.Ventral setae short and uncinate.
Remarks.-Earlier recorded from benthic habitat in Andaman Sea and from a drifting log off Puri, Orissa.The present specimen was collected frODl under a stone.Day (1953)   Description.-Probosciswith 1st lobe having 2 paragnaths in a line, 2nd with 9-10 in a cluster, 3rd with many in a group, 4th with many small and large ones, 5th with only one small one, 6th with 2 transversely Battened ones, •7th & 8th with several arranged in 2 rows.Dorsal setae homogomph spinigers.Ventral setae heterogomph falcigers and hetero .. gomph spinigers.Dark brown median line present on the dorsal side of the anterior segments.
Remarks .-This is the first record of this species both from the Andaman and the Indian waters.Earlier reported from Diamond Island, Burma.Description.-Tentaclesand tentacular cirri smooth.Gill filamen~s simple, commencing from 24th segment and extending upto 40t11.Dorsal cirri approaching in length to that of gill filaments.Parapodia with acicular bidentate setae, yellow coloured, comb setae, winged capillary setae and falcigerous setae.

Perinereis cultrifera var. helleri Grube
Remarks.-The specimen is reddish brown in colour without any coloured dots and collar on 4th or 5th segments.This is the first record of this species from the Indian waters.Earlier it has been reporte<;t from Persian Gulf.
EUDic.e antennata Savigny Description.-Bodyelongated, cylindrical and brown in colou~ with small white punctations only over the anterior portion.A white collar on 5th segment present.Gills commencing from 14th segment.Gill filaments single on first few seg~eI).Js, 4 . . .6 on others, gradually decreasing posteriorly, and finally absent on the last segments.Parapodia with acicular bidentate setae black-coloured, comb setae, capillary setae and falcigerous setae.
Renzarks.-Thespecimens were collected from corals.This is the    Description.-Opercularstalk with lateral wings.Operculum with a round calcareous plate having 2 branched processes.Thorax having 7 segments of which the first with bayonet shaped setae, and the remaining with winged capillary setae.Abdomen long, cylindrical and many segmented.Abdominal parapodia with trumpet-shaped setae.
. .Median tentacleabsent, lateral tentacles one pair.Eyes two pairs.Elytra covering the whole body 13 pairs, each divided into polygonal areas.Dorsal setae many and spinulose, ventral setae stout and unidentate.
ment.U ncinigerous tori appearing frOln 3rd setigerous segnlent.Tori with avicular u.p.cini in single rows.Abdomen with 25-30 segments with pinnules well protruded.~enlal'ks .-This is the first record of this species fro111 the Andaman waters.Earlier recorded froln Gulf of Mannar.