Jurnal Moluska Indonesia

Front Matter

adminwebsitejmi adminwebsitejmi — Thu, 08 Oct 2026 00:00:00 +0700

Front Matter

Inventory and Morphological Description of Land Snails in the Gunung Selatan Protection Forest, Tarakan Island

Chrizt jeensen palungan, Bimo Aji Nugroho, Vlorensius — Thu, 08 Oct 2026 00:00:00 +0700

Gastropods are generally found in aquatic areas, but some gastropods live in terrestrial environments, such as land snails. Forests are ideal habitats for land snails, such as the protected forest area of the southern mountain in Tarakan City. However, preliminary data on land snail species in this area is still limited. This study aims to identify and describe land snail species in the protected forest of the southern mountain in Tarakan City. This study used a purposive sampling method at four research stations, establishing 20 x 20 m plots at each station. Sampling was carried out by four researchers from morning to afternoon at each station, exploring the research plot area and measuring abiotic parameters such as temperature, light intensity, air humidity, soil moisture, and soil pH. The results revealed five land snail species: Macrochlamys tersa, Dyakia rumphii, Japonia borneensis, Quantula striata, and Kaliella doliolum. Furthermore, the measurement results for the parameters indicate conditions favorable for the survival of land snails.

The Identification and Morphological Description of Parmarion martensi in The Protected Forest Area of The Southern Tip of Tarakan

lisdawati lisdawati, Bimo Aji Nugroho, Nursia Nursia — Thu, 08 Oct 2026 00:00:00 +0700

This study aims to identify and describe the morphology of shell-less snails (slugs) in the Gunung Selatan Protected Forest area of Tarakan City. The research used a descriptive qualitative approach with a purposive sampling method. Sampling was conducted from November to December 2025 at four observation stations, each using a 20 x 20 meter plot. The results showed that one shell-less snail species was found at all observation stations, namely Parmarion martensi. This species has unique morphological characteristics in the form of a reduced shell as a form of adaptation to its environment. Environmental conditions at the study site support the survival of this species with average parameters: light intensity 226–911 lux, soil pH 5.2–6.0, air temperature 25.8–29.5°C, air humidity 84.8–94% RH, and soil moisture 3.5–4.5%. This data can help understand the concept of morphological adaptation and the relationship of living things to their environment through real phenomena in the surrounding environment

Exploitation Rate of the Bade-Bade Clam (Isognomon isognomum) in the Waters of Tapulaga Village, Southeast Sulawesi

Bahtiar Bahtiar, Farid Yasidi — Thu, 08 Oct 2026 00:00:00 +0700

The bade-bade clam is a bivalve that plays an ecological role and is utilized by local communities as a food source. One area suitable for the survival of this clam is the waters off Tapulaga Village. This study aims to determine the level of bade-bade clam exploitation based on growth parameters and population mortality rates in the waters of Tapulaga Village, Konawe Regency, conducted from December 2025 to February 2026. The research method employed was manual sampling (hand picking) without size selection in the intertidal zone during low tide. Length frequency distribution data were analyzed using the Sturges formula, while growth parameters were analyzed using the ELEFAN method and the von Bertalanffy growth model. Mortality and exploitation rates were analyzed using the length-converted catch curve method and Pauly’s empirical equation, both accommodated within the FiSAT II version 3.0 program. The total sample of bade-bade clams during the study was 768 individuals. Growth analysis results showed the asymptotic length (L∞), growth coefficient (K), and estimated t0 value for bade-bade clam growth at 152 mm, 1.40, and -0.072, respectively. The results of the mortality analysis showed a natural mortality (M) of 1.46, a fishing mortality (F) of 3.53, and a total mortality (Z) of 4.99. The exploitation rate (E) was 0.71, indicating that the exploitation of bade-bade clams in the waters of Tapulaga Village is classified as (over-exploited).

Relationship Between Dominant Substrate and Gastropod Abundance and Distribution in the Coastal Area of Tarakan Island

Hardianto s umar, Bimo Aji Nugroho, Ermawaty Maradhy — Thu, 08 Oct 2026 00:00:00 +0700

Coastal ecosystems are subject to ecological pressures that may alter the physical characteristics of benthic substrates. This study aimed to identify the dominant substrate types and analyze their correlation with the distribution patterns and abundance of gastropods along the coast of Tarakan Island. The study was conducted in the mangrove areas of Tarakan Island across four stations, with fieldwork taking place from September to October 2026. Sampling was conducted at four stations using a transect method with 1 × 1 m plots. Data were analyzed using the Morisita Index, One-Way ANOVA, Spearman Correlation, and Fisher’s Exact Test. The results recorded 20 gastropod species, with distribution patterns generally exhibiting a clumped distribution. Substrate characteristics across all sites were predominantly composed of fine-grained sediments (silt fraction), forming silty loam and silty clay loam texture classes. Statistical analyses indicated no significant differences in gastropod abundance among stations and no significant relationship between sediment fractions and either gastropod abundance or distribution patterns (p > 0.05). The homogeneous substrate conditions across the study sites did not promote significant niche differentiation; therefore, biological and behavioral factors likely played a more dominant role in determining the spatial distribution of gastropods.

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

Mega Marshella, Bimo Aji Nugroho, Ermawaty Maradhy — Thu, 08 Oct 2026 00:00:00 +0700

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.

Back Matter

adminwebsitejmi adminwebsitejmi — Thu, 08 Oct 2026 00:00:00 +0700

Back Matter