Journal of Advances in Biology & Biotechnology

Gall-inducing insects occur on the principal host plants used for Muga silkworm rearing, but comparative descriptions of their developmental stages remain limited. Gall-inducing insects associated with the major Muga silkworm food plants, Som (Persea bombycina) and Soalu (Litsea polyantha), were examined at the Department of Sericulture, Assam Agricultural University, Jorhat. Gall-infested leaves were collected at different stages of gall development, and insects were obtained by dissecting the galls and rearing mature galls until the emergence of adults. The gall-inducing insects were identified as Asphondylia sp. (Diptera: Cecidomyiidae) on Som and Pauropsylla beesoni Laing (Hemiptera: Psyllidae) on Soalu. Asphondylia sp. passed through four larval instars and a pupal stage, whereas P. beesoni completed five nymphal instars before reaching adulthood. The immature stages differed in body length, colour, body shape, antennal development and the presence of characteristic structures. The mean body length of Asphondylia sp. larvae increased from 0.95 ± 0.018 mm in the first instar to 2.51 ± 0.014 mm in the third instar, followed by a slight reduction to 2.32 ± 0.016 mm in the fourth instar. In P. beesoni, body length increased progressively from 1.02 ± 0.024 mm in the first instar to 3.08 ± 0.046 mm in the fifth instar. Adults of Asphondylia sp. measured 3.24 ± 0.017 mm in length, whereas adults of P. beesoni measured 2.34 ± 0.043 mm. The adult morphology of both species showed adaptations associated with their respective taxonomic groups, including the hind wings reduced to halteres in Asphondylia sp. and the jumping hind legs of P. beesoni. The findings provide baseline morphological information for recognising the gall-inducing insects associated with Som and Soalu and may support future studies on their biology, seasonal incidence and management in Muga silkworm food-plant plantations.