A CONTRIBUTION ON THE ESTUARINE ODONATA OF EAST INDIA

Thirty five species of Odonata from the estuarine areas of East India (West Bengal and Orissa) are recorded by FRASER AND DOVER (1922), MITRA et ale (1976), PRASAD AND GHOSH (1982) and RAM et ale (1982). In the present communication 30 species under 21 genera are reported from these areas, of which 10 spp., Lestes viridula Rambur, Copera annulata (Selys), Pseudagrion rubriceps Selys, Pseudagrion australasiae Selys, P seudagrion spencei Fraser, Aciagrion pallidum Selys, Ischnura aurora (Brauer), Agriocnemis lactiola Selys, Potamarcha obscura (Rambur) and Tholymis il/arga (Fabricius), are reported for the first time. Out of these, seven are new records for the estuarine areas of West Bengal and three for the estuarine are of Orissa. The study raises total number of species known from East India to 42. In this paper a check-list, brief field notes and keys for species are given.

Remarks: Agrees fairly well with the published description of the species, but it differs by having 10-11 postnodal nervures in forewings and 11 in hindwings.Specimen was observed very active and flying within the dry long grasses present at the side of the pond.The pond is situat~d very nearer to rhe sea shore.It is recorded for the first time from the estuarine area of West Bengal.

Lestes elata Hagen
Remarks: 12 postnodal nervures in forewings and 11 in hind wings.Specimens were seen flutering above the pond water under the shadow of small bushes and aquatic vegetation present beneath the tree at the side of pond.Pairs were also observed in tandem flying above the surface of water.It is recorded for the first time from the estuarine area of West Bengal.
Remarks: A very common species and recorded almost throughout the year nearby the estuariue areas of east India.Both males and females were observed in• tandem and in copulation wheel position.Oviposition behaviour was also recorded during the course of collections.Distribution: Assam, Himachal Pradesh, Coorg, Uttar Pradesh, West Bengal, Borneo, Burma, Sri Lanka, Malaysia and Sumatra.

Records (Jf the Zoological Survey of India
Remarks: Adults were seen at the temporary and permadent water bodies near the sea shore.During the collection period males and females were seen commonly in tandem position. 6. PseudagrioD microcephalum (Rambur) Remarks: During the course of collection of specimens it was seen that it is very common all along the sides of a pond.Specimens were resting on twigs.These are very small in size and length in comparision to the other common Remarks: A most common species in the estuarine area of east India.Swarms of this species were mostly seen either at seashore or sometimes they were flying above the sea water and moves upto 10 to 20 metres in side the sea.Specimens of Tramea basi/oris burmeisteri Kirby were also seen in its swarm.Distribution: Himachal Pradesh, Punjab, Rajasthan, Uttar Pradesh, West Bengal, Burma, Sri Lanka and Malaysia.

Key to the Odonata 0.( Estuarine area of East India
A key to the 42 species 01 Odonata under 30 genera and 7 families known to occur in Estuarine areas of East India is given below.Fraser (1933, 1934, 1936 and 1957) has been adopted with some modifications.Altogether 42 species of Odonata are recorded from the estuarine area of East India.Out of these 7 are new records for the estuarine area of West Bengal and 3 for the estuarine area of Orissa.