Ecological Approval for Cave Habitat: The Occurrence of Regressed Stridulatory System in Cavernicolous Homoeogryllus sp.

Subterranean caves are always characterized by several uncommon ecological factors due to which a high degree of biological adaptation is always required to establish any population in it. In the present work, the morphology of the sound producing organ of a cave cricket Homoeogryllus indicus has been studied and the ecological importance of the same has been tried to correlate with its habitat. Fifty adult male individuals of H. indicus were collected from Kachhuwa-Pahar cave and preserved separately in plastic veil containing 4% formalin. Complete stridulatory apparatus was studied under a binocular microscope and the sketches of the tegmina and teeth were drawn by using camera lucida mounted on the microscope. The total number of teeth present in both the files were found to be comparatively less in number than the other members of the same genus which represents an example of regressed evolution. However, a comparatively regressed stridulatory system observed in this species along with other reported morphologically regressive characteristics has been discussed from the perspective of ecological fitness for cave life.