Identification and Description of Freshwater Snails in the Lotic Waters of North Kalimantan

Abstract

Freshwater snails are one of the organisms commonly found in aquatic ecosystems and play a role in maintaining environmental balance. North Kalimantan has many rivers and tributaries that have the potential to become habitats for various types of freshwater snails. Changes in aquatic habitat conditions can potentially affect the presence of freshwater snails and even lead to the extinction of certain species before their existence is identified. However, data on freshwater snails in the North Kalimantan region are still limited; this research is based on the lack of data regarding freshwater snails in the area. Based on these findings, the aim of this research is to identify and describe freshwater snails. The research method uses line transects, with three transects at each station placed along the left bank, middle, and right bank of the tributary. Each transect consists of 10 plots measuring 1x1 m. The research successfully identified five species of gastropods, namely Sulcospira testudinaria, Clea nigricans, Filopaludina javanica, Pila saxea, and Radix rubiginosa. Morphological analysis shows that S. testudinaria has the largest shell size (average length of 63.5 mm) with the widest habitat distribution, while R. rubiginosa is the smallest (8.5 mm). The physicochemical parameters of the water overall still meet environmental quality standards, with variations in current speed and substrate type as the main ecological factors controlling the local distribution of the five species. Variations in shell morphology characteristics such as apex structure, number of whorls, aperture shape, and operculum size are the main basis for the taxonomic identification of freshwater snails in this water area.