Short Communication: Presence of the vulnerable freshwater goby Sicyopus auxilimentus (Gobiidae, Sicydiinae) on Sangihe Island, Indonesia

Abstract

Abstract. Hasan V, Valen FS, Islamy RA, Widodo MS, Saptadjaja AM, Islam I. 2021. Short Communication: Presence of the vulnerable freshwater goby Sicyopus auxilimentus (Gobiidae, Sicydiinae) on Sangihe Island, Indonesia. Biodiversitas 22: 571-579. A single specimen of freshwater goby Sicyopus auxilimentus was photographed and collected using fish traps between 8 and 15 September 2019 in the Laine waterfall, Sangihe island district, North Sulawesi Province, Indonesia. S. auxilimentus is amphidromous that live in both freshwater and marine environments. This species is currently listed as Vulnerable (VU) within the IUCN Red List Status. The specimen was identified as male S. auxilimentus based on the coloration of the preserved specimen: background yellowish; scale edges brown; posterior flanks and caudal peduncle orange; first dorsal fin black, second dorsal fin dusky black; pectoral fin slightly brown; ventral fin slightly dusky; anal fin blackish; caudal fin dusky brown. Specific morphological features were as follows: the base of the first dorsal fin was not connected to the second dorsal fin base; distance between the base of first and second dorsal fin was generally less than half of eye diameter; ventral fin rays were fused to belly only between fifth rays; posterior margin of caudal fins rays was rounded; scales were all ctenoid; scales appeared on the caudal peduncle, and between anal and second dorsal fins; anterior to which, scales became widely spaced and did not imbricate. Meristic characters were as follows: first dorsal fin rays VI; second dorsal fin rays I+9; ventral fin rays I+5; pectoral-fin rays 14; anal-fin rays I+9; caudal-fin rays 13; scales in lateral series 13; scales in zigzag series 7; scales in transverse series backward 7; scales in transerves series forward 4. This finding is considered the first record in Sulawesi and the fifth from Indonesian waters after findings in Halmahera, Java, Bali and Lombok. This record enhances the understanding of the distribution of S. auxilimentus in Indonesian waters. Monitoring is needed to assess the possibility of Sangihe Island being a growth ground, spawning ground, and/or on the migration route of S. auxilimentus. In the Laine waterfall, Sangihe island, freshwater conditions were as follows: salinity 3.5 psu, temperature 23-25°C, and dissolved oxygen 7.7-9.2 mg/l, which were ideal habitat for S. auxilimentus. S. auxilimentus from Sangihe Island, had 0.000 genetic distance than from S. auxilimentus from Bali, while the next closest genetic distance was S. zosterophorus at genetic distance of 0.090. In addition to onsite conservation, domestication programs are needed to increase commercial availability without depending on natural catches.

First and recurrent records of Stiphodon surrufus Watson & Kottelat, 1995 (Gobiiformes, Gobiidae, Sicydiinae), a naturally rare amphidromous goby, in Sulawesi, Indonesia

“…Understanding the distribution of sicydiine gobies is important in the context of amphidromous species diversity and biogeography (Ebner et al 2011;Maeda and Palla 2015;Hasan et al 2021). Our new distributional data on S. surrufus reinforces indications of historical and/or contemporary connectivity of amphidromous species between Sulawesi, in particular the Gulf of Tolo coast of eastern Sulawesi, and other islands in Wallacea and eastern Indonesia more generally, including the Sahul Shelf ecoregion.…”

Cytochrome Oxidase C Subunit I (COI) for Identification and Genetic Variation of Loaches (Nemacheilus fasciatus)

“…Further research, we suggest to applicate this method to other native or non-native fish that appear in Indonesian waters, such as Arapaima (Fadjar et al, 2019), Aligator gar (Hasan et al, 2020), Channidae (Pratama et al, 2020), Gobiidae (Hasan et al, 2021), Cichlidae (Insani et al, 2020), and Cyprinidae (Hasan et al, 2019).…”

Profile of Amino Acid and Fatty Acid from Different Type of Worm as Feed of Broodstock Candidates for Domesticated Uceng (Nemacheilus fasciatus)

“…Deficiency of essential fatty acids will disrupt fish health, including reduced fecundity and ability to form embryos, death of abnormal larvae and growth, defective pigmentation, inability to eat at a low light intensity, abnormal behavior, and decreased membrane function at temperatures low (Tocher, 2003). We recommend that further researchers conduct similar research using tested fish that are often cultivated and have economic value such as tilapia (Insani et al, 2020); Genggehek (Valen et al, 2019); Gobiidae (Hasan et al, 2021a); Beardless barb (Hasan et al, 2021b).…”