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

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.

Rhinogobius houheensis, a new species of freshwater goby (Teleostei: Gobiidae) from the Houhe National Nature Reserve, Hubei province, China

A new freshwater goby, Rhinogobius houheensis, is described based on 40 specimens in a freshwater stream from the Houhe National Nature Reserve, Hubei Province, China. The new species can be distinguished from all its congeneric species by the following combination of characters: thee first dorsal fin rays VI, the second dorsal fin rays I/9-I/10; anal fin rays I/7-I/8; pectoral-fin rays 16–17; longitudinal scale series 37–40; transverse scales 12–14; predorsal scale series 0; and vertebrae counts 12+18=30. The first three spinous rays in the first dorsal fin are colored with two dark-blue stripes and one black spot in alive.

Breeding Biology of Freshwater Goby Glossogobius Giuris Using Gonadosomatic Index and Gonadal Histology

The breeding season of fishes plays an important role in fish domestication and conservation of fish diversity. Freshwater goby, Glossogobius giuris is an important food fish of Bangladesh. Therefore, a study was performed to determine the breeding biology through assessing the gonadosomatic index (IG), fecundity and histology of gonad of G. giuris. A total of 1371 females and 1051 male fishes were collected from the Belai beel of Gazipur district. Significantly (P<0.05) higher values of mean IG were observed during March and from June to August for both females and males. The highest mean fecundity was recorded in August and the lowest was recorded in May. The smallest mean oocyte length was 0.037±0.005 mm in May and the largest was 0.071±0.001 mm in August. The early and late perinucleolar stages of oocytes were observed from January to March. The yolk vesicle stage was observed during April to May and yolk granule stage was observed during March and from June to August. These results revealed that G. giuris might breed in March and from June to August. Ann. Bangladesh Agric. (2019) 23(1) : 1-13

IDENTIFICATION OF FRESHWATER GOBY SPECIES FROM THE BIAK AND KOYOAN RIVERS, LUWUK BANGGAI, CENTRAL SULAWESI

Sulawesi is an island famous for its biodiversity, including many endemic species. In particular, Sulawesi has the highest number of gobies in the world, including species with potential as food and/or ornamental fishes. The exploration of freshwater ichthyofauna is important in the context of Indonesian and global biodiversity. This research aimed to identify gobies found in the Luwuk Banggai area of Central Sulawesi, as a contribution to the exploration of Indonesian ichthyofaunal biodiversity. Gobies were sampled from January to March 2019 in the Biak and Koyoan Rivers. The sampled fish were measured and identified based on morphological characteristics. A total of 52 specimens were collected, and identified as belonging to 17 species within two families, the Gobiidae and Eleotridae. Gobies from the Koyoan River comprised 32 specimens from 8 species, while 20 specimens belonging to species were found in the Biak River. Only two species were found in both rivers: Stiphodon semoni and Sicyopterus lagocephalus. These results augment the body of knowledge regarding the presence and distribution of gobies in Indonesia