Diversity and Distribution of Gastropoda and Bivalvia in Mangrove Ecosystem of Pelangan, Sekotong, West Lombok

One group of invertebrates that live in the mangrove ecosystem is Mollusks mainly Gastropods and Bivalves. They are associated with as life, shelter, spawning, also a place to get food support growth them. The purpose this reaserch was look at effect species substrate type on distribution (Gastropods Bivalves) Pelangan Village, district Sekotong, west Lombok regency. This descriptive explorative. Sampling done by purposive sampling method determine tree species, size, substrate. Repeatation held six times each species. results showed there 25 speciesd mollusk ecosystem, most abundant gastropod Clypeomorus moniliferus value 6.9 ind / m2 contained Osbornia octodonta. As for gastropods bivalves not affected but influenced environmental factors which case