THE BIODIVERSITY OF GASTROPODS IDENTIFIED IN THE MANGROVE FOREST OF BABAN VILLAGE, GAPURA DISTRICTS SUMENEP REGENCY AS THE RESOURCE OF LEARNING BIOLOGY

Gastropods are the animals that utilize their gastro as their only medium for making a movement – it is derived from
the words gastro (thing like a tummy, stomach, and you name it) and pods (thing like feet to walk or to make a
movement). The existence of that class, nowadays, is being threatened due to the damage that happens to the
ecosystem of mangrove forest and is caused by land conversion. As the consequence, it causes an ecological damage
as well, which is allowed to obstruct the evenness of the ecosystem of mangrove forest. In addition to the aforeposed problems, the lack of information regarding the diversity of Gastropods, particularly at the most isolated
area, such as Baban Village, Sumenep Regency, is also considered as another problem that might negatively affect
the existence of Gastropods. Therefore, this research aimed to investigate the diversity and the community structure
of Gastropods within the area of mangrove forest of Baban Village, Gapura Districts, Sumenep Regency.
Moreover, the emphasis of this research was on the Gastropods that are living within the area of mangrove forest.
The researcher, furthermore, employed descriptive research. The research itself was conducted on April 17th to
April 24th once the tide went low by occupying randomized sampling method through square transect. The data,
afterwards, were collected right after the direct observation on the predetermined population was completed. The research revealed that Gastropods that had been already found out comprised 11 species, namely Nerita fulgurans, Cassidula aurisfelis, Telescopium telescopium, Cerithidea quadrata, Ceritiopsis sp, Littroraria scabra,
Raphitoma purpurea, Alvania sp, Littoraria melanostoma, Terebralia sulcata, dan Littorina sp. Meanwhile, the community structure of Gastropods was based on the following things:(1) the highest density index of Gastropods went to the species Terebralia sulcata (converted to 2.17 individual per square meter), whereas the lowest one was
the species Nerita fulgurans (accumulated to 0.25 individual per square meter). (2) The highest importance value
index were achieved by the species Terebralia sulcata, which constituted 0.33%, while, the lowest one was
attributed to the species Nerita fulgurans, which signified 0.05%. (3) The diversity index was categorized as
standard, which was converted from 1.84 to 2.16. (4) The index of evenness illustrated that Gastropods were nearly
evened in every single station, started from 0.77 to 0.90. At last, (5) the dominance index communicated that, in
Gastropods class, there were not any dominant species. Expectedly, the result of this research can be utilized as the
resource of learning Biology, in the form of Booklet.