Amblygobius semicinctus
A small burrow-dwelling goby most reliably logged in the Central Atolls, Maldives, on sandy reef flats warmed to 26-29C year-round.
A slim 8 cm goby with a pale, whitish to sandy-grey body crossed by a series of dark vertical bars concentrated toward the rear half of the body, giving it the half-barred look. It hovers close to a burrow in sand or rubble patches rather than clinging to rock, with a blunt head and the two-part fin arrangement typical of gobies. Look for the bars fading toward the front of the body, which is the quickest cue separating it from more evenly striped relatives.
Divers usually spot it hovering just above or beside a burrow entrance in sand or coral rubble, ready to dart in in the face of any sudden movement. It feeds by picking over the sediment close to its burrow rather than roaming the reef, and it is generally unbothered by a diver holding still a metre or two away. Most sightings come from calm, sandy-bottomed patches rather than current-swept reef faces.
Like many burrow-associated gobies, it likely shares its burrow with a pistol shrimp that excavates the tunnel while the goby stands guard, a partnership common across the shrimpgoby family it resembles.
Sightings show no detectable seasonal pattern, and the observed water temperature range of 25.7 to 29.3C spans the whole year on these reefs, so it is a year-round find rather than a seasonal one.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
This is very much a Maldives fish in the logged data, most commonly recorded across the Central Atolls, with a single confirmed sighting from Blue Bay, Mauritius. Divers targeting sandy lagoon edges and reef flats in the central Maldivian atolls have the best odds, where it turns up as an uncommon but steady find on many sites and a common one on a smaller number.
Mapping where Half-barred Goby is logged…
The Central Atolls of the Maldives are the most reliable place to find it, turning up on sandy reef flats and lagoon-edge patches. A single sighting has also been logged at Blue Bay, Mauritius.
There is no clear season in the sighting data. Water stays between about 25.7 and 29.3C on these reefs all year, so it can be found any month.
Look for a small, pale goby around 8 cm long with dark bars crossing the rear half of its body, hovering near a burrow in sand or rubble. The front of the body is plainer, which helps separate it from more evenly barred prawn-gobies.
They stay small, typically reaching around 8 cm in length, which is average for a burrow-dwelling goby.
It is likely, following the pattern seen in closely related gobies, where a pistol shrimp digs and maintains the burrow while the goby watches for predators and signals danger.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Slender Goby
803 sites
