Life Cycle Dynamics and Stage-wise Microscopic Analysis of Naturally Occurring Drosophila spp. on a Banana Substrate

Drosophila spp. is widely used as a laboratory organism because of its short developmental cycle, readily observable morphology and ease of culture. The present study documented the major developmental stages of Drosophila spp. maintained on rotten banana under laboratory conditions and examined selected stages microscopically. The culture was established in the Zoology Laboratory of Bhima Bhoi Degree College, Rairakhol, Odisha, during November 2025. Banana was placed in a transparent container that allowed flies to enter, after which eggs, larvae and pupae were collected and examined using a light microscope. Photographs were taken to document developmental changes. The observed developmental sequence included the egg, three larval instars, pupa and adult stages. Under the culture conditions, progression from egg to adult emergence occurred over approximately 7 days. Microscopic examination permitted recognition of stage-associated morphological characteristics, including changes in larval body form, feeding structures and pupal appearance. Adult males and females were also differentiated using external morphological characteristics. The observations demonstrate the practical usefulness of simple culture and microscopy techniques for visualising the successive developmental stages of Drosophila spp. However, developmental timing was based on descriptive observations rather than replicated quantitative measurements, and environmental conditions and individual specimens were not continuously monitored. The study therefore provides a descriptive account of development under the particular culture conditions employed.