OOTAXONOMIC INVESTIGATION OF 3 SPECIES OF MYCOMYA (DIPTERA, MYCETOPHILIDAE) - A SCANNING ELECTRON-MICROSCOPE STUDY

The egg-shell structure of three fungus-gnat species of the genus Mycomya (M. occultans, M. marginata, M. fimbriata) was investigated by scanning electron microscope (SEM). Each species, pear-shaped with a single micropyle located at a pole, shows some distinctive characters in egg morphology, namely different egg shape and size, together with chorionic sculpturing of the micropylar area, egg surface and a specialized ventral area. The latter, interpreted as a plastron, is detected for the first time in the eggs of Mycomyinae. Ootaxonomic data of these species are compared with those of other Diptera and discussed in relation to adult behaviour and the microclimatic conditions of the laying biotope.