The twinspot goby (Signigobius biocellatus) is a small fish found on coral reefs in the western Pacific. It is easily recognized by its two large eyespots, which look like eyes, on its dorsal fins.

This small goby usually lives on sandy or muddy bottoms and spends much of its time near its burrow, which it often shares with a partner. It moves along the bottom in search of food and sifts sand with its mouth to extract small animals.

The twinspot goby has an elongated body ranging from bluish gray to yellowish brown, with several brown spots and markings. A thin brown bar crosses the head below the eye, and several irregular bands are visible along the sides. Its pelvic and anal fins are dark and covered with small blue spots.

Each of its two dorsal fins bears a large dark eyespot surrounded by several colors. These false eyes are especially visible when the fish spreads its fins. Its caudal fin is rounded and slightly translucent.

The twinspot goby inhabits tropical waters of the western Pacific Ocean, from the Philippines and Palau to the Solomon Islands and Vanuatu, and southward to the southern part of the Great Barrier Reef.

The twinspot goby mainly lives on sandy or muddy bottoms in lagoons and coastal bays. It is generally found between 6.5 and 98 feet deep, often near rocks, coral rubble, or plant debris that can provide shelter.

Adults generally live alone or in pairs and often share a burrow dug into the sand. The fish stays close to this hiding place and can quickly retreat into it when threatened.

The twinspot goby feeds on small invertebrates living in the sand. It takes mouthfuls of sand and sifts through them to extract the animals it is looking for. After collecting its food from between the grains, it spits out the sand and starts again a little farther away.

Reproduction in the twinspot goby is still poorly known. The species usually lives in pairs and appears to form monogamous bonds.

Its two large eyespots look like real eyes when the twinspot goby spreads its dorsal fins. This highly visible feature gives the species its English common name, Twinspot goby.