SEM studies on the morphological adaptations of Trichoptera and Ephemeroptera of a western Himalayan hill stream

Studies made on the ecology of a Seer stream of western Himalaya revealed that torrential and turbulent nature of its water poses a great difficulty for the organisms to survive. The collected trichopteran and ephemeropteran larvae have been observed to possess many morphological features which serve as their adaptations for the fast flowing waters. The larvae of Rhyacophila obliterata and, Hydropsyche instabilis were found to possess stridulatory apparatus, net spinning capacity and C-shaped modified tarsal claws. In R. obliterata silk filament comes out from the posterior region which helps the insect to make firm contact and also in diving. Ephemeropterans (Rhithrogena pellucida, Choroterpes terratoma) have depicted a peculiar sitting position and friction pads with fine serrated spines, circlets and alternate arrangement of small and long spines have been noticed on the ventral side and on the legs.