A preliminary report on Drosophilids of Mokokchung (Nagaland State, India).

Chandra, Y. Sharat^1,3, S.N. Hegde², and M.S. Krishna².  ¹Department of Zoology, Nagaland (Central) University, P.B. No. 89, Mokokchung-798 601, Nagaland, India;  ²Department of Studies in Zoology, Manasagangothri, Mysore University, Mysore- 570 006, Karnataka, India;  ³for correspondence, email: yschandrays@rediffmail.com

      Significant progress has been made in the field of taxonomy and systematics of the family Drosophilidae (Diptera) in India.  About two hundred species belonging to its twenty genera were reported from different parts of the country to date.  However, a vast area of great ecological interest still either awaits exploration or is poorly explored.  Particularly, very little is known regarding Drosophilid fauna of North Eastern region of the Indian subcontinent despite this region being one of the richest repositories of biodiversity in the world (Dwivedi and Gupta, 1979; Dwivedi et al., 1979, 1980;  Gupta, 1973;  Gupta and Singh, 1979;  Singh, A., 1972;  Singh, O.P., 1987;  Singh and Gupta, 1977;  Sreerama Reddy and Krishnamurthy, 1971).  This region includes seven hill states, namely Assam, Arunachal Pradesh, Manipur, Meghalaya, Mizoram, Nagaland, and Tripura.

Table 1.  Drosophila species collected at Mokokchung (Nagaland, India). Species Subgenus Number 1.  D. immigrans Drosophila 92 2.  D. nasuta Drosophila 34 3.  D. takahashii Sophophora 20 4.  D. kikkawai Sophophora 10 5.  D. nepalensis Sophophora 08 6.  D. suzuki Sophophora 04 7.  Picture winged Drosophila (unidentified) 03 8.  Picture winged Drosophila (unidentified) 02 Total 173

      A preliminary survey on Drosophilids of Dimapur, Medziphema, and Kohima of Nagaland was conducted by Singh (1987).  However, no information is available about the other parts of the state so far.  Mokokchung is a hill station in Nagaland situated at latitude 26°11’ - 26°45’ and longitude 94°17’ - 94°45’.  This place is situated at an altitude of 1350 meters above the sea level characterised by subtropical, semi evergreen forests.  The annual rainfall is about 250-310 cm, and temperature in the area ranges from 2°C to 32°C.

      Of late, collections were made using fermenting fruits as baits.  Altogether 8 different Drosophila species were collected (Table 1).  Of them, two species are unidentified.  Both the species bear characteristic marks on the wings (picture winged Drosophila).  D. immigrans constitutes more than half of the catch, followed by D. nasuta.  This is in conformity with the observation of Sreerama Reddy and Krishnamurthy (1971), who worked on Drosophilids of Nilgiris and Kodaikanal ranges of South India that D. immigrans thrives well in a most and humid climate. 

      Acknowledgments:  We thank Dr. O.P. Singh, Mizoram University, for his help.  Y. Sharat Chandra thanks Prof. Pardeshi lal and Dr. S.U. Ahmed, Head, Department of Zoology, Nagaland University, for their encouragement. 

      References:  Dwivedi, Y.N., and J.P. Gupta 1979, Entomon 4: 183-187;  Dwivedi, Y.N., and J.P. Gupta 1980, Proc. Ind. Acad. Sci. (Ani. Sci.) 89: 85-89;  Dwivedi, Y.N., B.K. Singh, and J.P. Gupta 1979, Oriental Insects 13: 61-74;  Gupta, J.P., 1973, Dros. Inf. Serv. 50: 112;  Gupta, J.P., and B.K. Singh 1979, Entomon 4: 167-172;  Singh, A., 1972, Dros. Inf. Serv. 49: 78;  Singh, O.P., 1987, Dros. Inf. Serv. 66: 67;  Singh, B.K., and J.P. Gupta 1977, Proc. Zool. Soc. (Calcutta) 30: 31-38;  Sreerama Reddy, G., and N.B. Krishnamurthy 1971, Dros. Inf. Serv. 47: 116-117.