The females of marine gastropod Babylonia spirata along Chennai Royapuram Fishing Harbour and Tuticorin coast showed reproductive anomaly i.e. superimposition of male sexual characters, imposex. Imposex frequency (93.8%) and the percentage of females with stage 4 of imposex (18.8%) were higher in Chennai than Tuticorin. However, no marked difference in male: female sex ratio was observed in Tuticorin (1.2: 1) and Chennai (0.9: 1). A further morphological change in the form of double penis in a female was observed in Tuticorin. Vas Deferens Sequence Index (VDS) in Tuticorin and Chenhai Royapuram Fishing Harbour (1.7 and 1.8) were well below the critical index value of 4. No occlusion of genital pore \;as observed. This reproductive anomaly could be linked to Tributyltin (TBT) leaching from antifouling paints used in fishing boats and ships along these coasts.

Gastropod Babylonia spirata, imposex