Integrative Morphogenetics Validates the Distinctiveness of Glossogobius Flavipinnis (aurich 1938) from Lake Towuti in the Wallacea Biodiversity Hotspot

The Malili Lakes system in Sulawesi, a unique component of the Wallacea biodiversity hotspot, harbors several endemic aquatic organisms, including species of the genus Glossogobius. Prior to this study, both morphological and molecular data on Glossogobius species were lacking from this system, particularly for Glossogobius flavipinnis (Aurich 1938), which is endemic to Lake Towuti. Hence, the present study provides the first detailed characterization of the morphological traits of G. flavipinnis, along with evidence of sexual differentiation based on multivariate Principal Component Analysis. Additional diagnostic features, such as a moderately depressed head and a first dorsal fin with black rays and distinctly bright yellow membranes, further facilitate accurate species identification and reflect adaptations to its specific ecological niche in Lake Towuti. The first mitochondrial cytochrome c oxidase subunit I sequence (mtCOI) data obtained from morphologically identified G. flavipinnis revealed its genetic distinctiveness from 19 out of the 43 other Glossogobius species included in a curated mtCOI dataset, with uncorrected p-distances ranging from 14.15