Asterropteryx semipunctata
A 4cm speckled goby often overlooked on reefs in Queensland and the Visayas, sitting still in 25-29C water year-round.
A tiny goby, barely 4 cm, with a pale grey to translucent body scattered with fine dark speckles that give it a starry look under torchlight. It perches motionless on rubble, sponge or coral rather than swimming in open water, propped up on its pelvic fins like most gobies. Look closely rather than fast: at this size it is easy to swim straight past without noticing it at all.
Divers usually find it sitting still on a patch of rubble, dead coral or sponge rather than out swimming, using its fins to prop itself up and watch the reef go by. It tends to hold its ground as divers pass rather than bolting for cover, which is handy given how easily it disappears into the background otherwise. Most sightings come from shallower reef flats and slopes within the top 20 metres, where there is plenty of rubble and coral rubble for it to hide against.
Its speckled pattern works less like a warning sign and more like camouflage, breaking up its outline against rubble and coral rubble so it reads as background texture rather than a fish.
No clear seasonal pattern shows up in the sightings, and with a comfortable range of about 25 to 29C it has no real reason to disappear in any month, so treat it as a year-round find on tropical reefs.
Most reliably logged on reefs in Queensland, Australia, and across the Visayas in the Philippines, with strong showings too in Kalimantan, Indonesia, and around Nouméa in New Caledonia. Smaller but consistent counts come from Hawaii in the United States, Fiji's Mamanuca Islands, and Eilat in Israel, so it turns up across a wide spread of tropical and subtropical reef systems.
Mapping where Starry Goby is logged…
It shows up across a wide spread of tropical reefs, most consistently in Queensland, Australia, the Visayas in the Philippines, and Kalimantan, Indonesia. Nouméa in New Caledonia, Hawaii, Fiji's Mamanuca Islands, and Eilat in Israel also have logged sightings.
There is no strong season in the sightings, so it can be found year-round. It favours water between roughly 25 and 29C, which describes most tropical reef conditions for most of the year.
Look for a very small goby, around 4 cm, with a pale speckled body perched motionless on rubble or coral rather than swimming freely. Its size and habit of staying put on the substrate are the biggest identification clues.
It stays tiny, topping out at around 4 cm, so it is easy to overlook unless you are looking closely at rubble and coral surfaces during a dive.
No, it poses no threat to divers. It is a harmless, herbivorous reef fish that simply sits on the substrate and ignores passing divers.
At most sites where it has been recorded, divers describe it as uncommon rather than common or rare, so spotting one usually takes a bit of deliberate searching rather than a guaranteed encounter.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Slender Goby
803 sites
