MELANOIDES TUBERCULATA (MÜLLER, 1774) (MOLLUSCA: PROSOBRANCHIA: THIARIDAE): OCCURRENCE AND EXTENSION OF THE GASTROPOD TO KARACHI MANGROVES

At present virtually it is a tidal creek, this tidal creek connects the mangrove with adjacent areas and provide well-defined pathways for aquatic organisms and for water and material exchange. Since the empty freshwater shells float, the dead shells in our area may have reached here through river drift, the accumulations of small floating bits and pieces left behind by creeks and rivers after floods. Invasive species can have significant direct and indirect impacts on native biota, for example their impact on the shell utilization patterns of intertidal populations of hermit crabs (Van-Oosterhout et al., 2013). Since these gastropods cannot tolerate prolonged exposure to salinities above 25 PSU (Bolaji et al., 2011), their mortality results in an influx of empty shells to the marine environment. [...]it is imperative that greater efforts be directed toward monitoring the expansion of M. tuberculatus in the aquatic ecosystems of Karachi mangrove zone.