Hasan V, Andraini NE, Isroni W, Sari LA, Nafisyah AL, Dewi NN, Putri DNA, Prasasti TAB, Ramadhani AA, Daniel K, South J, Vieira LO, Ottoni FP, Maftuch, Faqih AR, Wirabuana PYAP, Tamam MB, Valen FS. 2023. Fish diversity of the Bengawan Solo River estuary, East Java, Indonesia. Biodiversitas 24: 2207-2216. Bengawan Solo River is the longest river in Java which flows from Mount Lawu and empties into the North Coast of Java. The watershed is a hot spot for fish species diversity, especially in the estuary area. The purpose of this study was to initiate an inventory of fish species, their abundance, and biodiversity assessment based on the Shannon diversity index (H'), evenness index (E), and dominance index (C) in the Bengawan Solo River estuary. The research was conducted from September to November 2022 at three stations with different ecological types and environmental conditions. Fish sampling was carried out using a gill net attached to a boat. In this study, 44 fish species from 22 families were identified. The highest abundance of fish was obtained from the Ariidae family, namely the Spotted sea catfish Arius maculatus (Thunberg, 1792) and Sagor catfish Hexanematichthys sagor (Hamilton, 1822). The fish diversity index obtained was 1.2-3.01, the uniformity index obtained was 0.7-0.92, and the dominance index obtained was 0.07-0.33. The H', E, and C at Station 2 have higher values ??than the other stations. The diversity expressed in H' values ??at the three research stations indicates that the mangrove in the Bengawan Solo River estuary area has a high diversity of fish species.

Isroni W, Sari PDW, Sari LA, Daniel K, South J, Islamy RA, Wirabuana PYAP, Hasan V. 2023. Checklist of mangrove snails (Gastropoda: Mollusca) on the coast of Lamongan District, East Java, Indonesia. Biodiversitas 24: 1676-1685. Mangroves are crucial transition zone ecosystems providing sheltered nursery zones and abundant marine and terrestrial biota resources. Mangrove snails (Gastropoda: Mollusca) are ecologically important ecosystem engineers, trophic links for higher predators, and a source of human food and livelihoods. Mangrove snails are also ideal bioindicators to monitor environmental pollution. A strong baseline understanding of current richness and distribution is therefore important. Thus, this study provides data on the species composition of mangrove snails on the north coast of Lamongan District, East Java, Indonesia. Sampling was conducted during low tide at four stations from September to November 2022 using square transects. Ten families consisted of Cerithiidae, Cypraeidae, Fasciolariidae, Muricidae, Naticadae, Neritidae, Plaxidae, Potamididae, Trochidae, and Turbinidae comprising 20 genera and 24 species. The most dominant family found is Muricidae, with six genera and eight species. Most mangrove snails were found in rocky, sandy substrates, around trees, and mangrove roots. Gastropods observed in this study were alive and dead (i.e., empty shells). We suspect that there is still much-hidden diversity of Gastropoda in this region. Therefore, we suggest that future work addresses differences in microhabitat and snail morphology with quantitative and semi-quantitative methods to understand distribution drivers and ecological roles better.

Pratama WW, Nursyam H, Hariati AM, Islamy RA, Hasan V. 2020. Short Communication: Proximate analysis, amino acid profile and albumin concentration of various weights of Giant Snakehead (Channa micropeltes) from Kapuas Hulu, West Kalimantan, Indonesia. Biodiversitas 21: 1196-1200. Fish is an important foodstuff due to its nutritional value and high protein. One of popular fish as a foodstuff in tropical Asia is giant snakehead fish (Channa micropeltes). This study aims to examine the proximate composition, amino acid profile, and albumin concentration of giant snakeheads in various weights and to determine the best weight of giant snakeheads according to the proximate, amino acid, and albumin concentration. This research used natural-caught giant snakehead as a material of study, which was categorized into 4 weight sizes consisting of 4-5 grams (B1), 6-14 grams (B2), 15-34 grams (B3), 35-300 grams (B4). Based on the results of the test, the highest water content was found in B1 of 80.5%, the highest levels of protein and fat were in the B4 group of 16.8% and 1.7%, respectively. The highest total amino acid profile was found in B4, with the highest composition of essential amino acids, lysine, which was 2.02%, while the composition of the highest non-essential amino acid in glutamate was 3.60%. The highest albumin levels were in the B4 group which was 16.7%. According to the result of this research, the best weight to consume according to the proximate analysis (Protein, fat content), amino acid profile, and albumin concentration is a giant snakehead at the weightiest of 35-300 grams (B4).

In 2018 we captured specimens of Oreachromis niloticus (Linnaeus, 1758) from Danau Kastoba, a crater lake on Bawean (Indonesia), a small, isolated island in the Java Sea. Additional individuals were later photographed. These records are among first of this species from an isolated island, in the Java Sea. A description of meristic and morphometric features of a specimen are provided.

In 2019 we captured specimens of Oreochromismossambicus Peters, 1852 from Batu Batu River, an estuary river on Kangean Island (Indonesia), a conservation area in the Java Sea. These records are among the first of this species from an island in the Java Sea. A description of morphological characters of sampled specimens is provided.

Stiphodon surrufus Watson & Kottelat, 1995, with its recent synonym S. birdsong Watson, 1996, is recorded from widely separated locations in the Western Pacific, including Papua and Halmahera in eastern Indonesia. We collected a single specimen of male S. surrufus from the Bohi River, Banggai District, Central Sulawesi Province, Indonesia in 2019; this represents the first record of S. surrufus from Sulawesi, the largest island in the Wallacea biodiversity hotspot. Three additional specimens were collected in 2020, one in 2021, and two in 2022, all from the same site. These records expand the known distribution of a naturally rare but widespread sicydiine goby and contribute to the underexplored but increasingly threatened Sulawesian riverine ichthyofauna.