Two small sunrise-colored gobies had passed through the hands of a fish exporter before anyone confirmed they represented a new species to science. The fish were caught in a fine-mesh hand net off Banyuwangi in East Java in August 2025. The exporter, CV Cahaya Baru, brought them to researchers, who determined that the pair belonged to a species no one had formally named.
A team led by Kunto Wibowo has now given the fish a name that fits its coloring, Tomiyamichthys oriens, Latin for "the rising sun," formally describing it in ZooKeys. Wibowo works at Indonesia's Museum Zoologicum Bogoriense, where both specimens are now kept.
“It is always exciting to discover a species that is new to science. We hope this finding will inspire further exploration of Indonesia’s fish biodiversity, where many small and overlooked species are likely still awaiting discovery,” Wibowo said in a press release.
New Shrimpgoby Species Differs From Its Japanese Relative
Barely over an inch long, the new species carries small yellow flecks across a pale body, set off by five bold orange blotches along each side. In males, two thread-like spines stretch backward from the first dorsal fin, a feature most of its relatives do not share.
Those colors changed after preservation. The orange and yellow markings faded, while the bodies became pale brown or milky white. Photographs taken when the specimens were fresh recorded the pattern used in the species comparison.
One species comes especially close. Tomiyamichthys, formally named from southern Japan in 2025, also has nine segmented rays in its second dorsal and anal fins. Males of both species grow the same pair of trailing spines.
Two other members of the genus share the nine-ray count, but their males have three elongated spines instead of two. That placed the Indonesian fish within a small group, leaving researchers to determine which species, if any, it matched.
They found differences in the smaller details, including fin-ray totals, scale counts, gill rakers, and the arrangement of the fish's colors. The Indonesian specimens had 18 pectoral-fin rays rather than 17, and 13 branched tail-fin rays rather than 14 or 15. They also had 60 or 61 rows of scales along the body, compared with 45 to 48 in the Japanese species.
Researchers also compared a stretch of DNA commonly used to tell species apart and found a 3.1 percent difference between the Indonesian and Japanese fish, supporting what the anatomy already suggested.
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Sunrise of Java Inspires the Oriens Shrimpgoby's Name
The team chose the name for two related reasons. The first comes from the fish's orange coloring, which calls to mind a sunrise.
The second comes from its home. Banyuwangi occupies the easternmost end of Java and is popularly known throughout Indonesia as the Sunrise of Java. The team selected Oriens Shrimpgoby as the species' common English name.
Indonesia Hosts More Tomiyamichthys Species Than Any Other Country
The shrimp-associated gobies in this genus range across the tropical Indo-Pacific, from the Red Sea and eastern Africa to Japan and Fiji. With the new addition, Indonesia now has 13 of the 21 recognized species, more than any other country.
Indonesia sits at the center of the Coral Triangle and supports an especially high diversity of gobies. Scientists documented the country's previously known Tomiyamichthys species through field collections and underwater photography.
For now, the Oriens Shrimpgoby is known only from the waters off Banyuwangi. Local fishers describe it living over sandy seafloor in shallow coastal water.
Wibowo hopes further surveys will document more of the small fishes that have so far escaped notice in Indonesia's waters.
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Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
- This article references information from a study published in ZooKeys: Tomiyamichthys oriens, a new species of shrimpgoby (Teleostei, Gobiidae) from the coast of Banyuwangi, East Java, Indonesia
