Tigrigobius dilepis
A pinhead-sized reef goby found perched on coral rubble in Cayman Brac and Saba's Tent Reef, in warm 27 to 28C water year-round.
A hair's-breadth fish at around 1 cm, so you're looking for a translucent body with a rusty-orange stripe or patch along the sides rather than any obvious silhouette. It perches motionless on rubble, sponge, or coral rather than swimming in open water, with big dark eyes that give away its position before the rest of it does. You'll need a slow approach and a sharp eye, or a macro lens, to pick out the orange flank marking against the reef背景.
Look for it sitting still on rubble, sponge, or low coral structure rather than darting about, which is typical goby behaviour for holding a favoured perch. Divers log it as uncommon to rare at most sites, so it takes a deliberate, slow scan of the substrate rather than a casual glance. It doesn't react much to a diver's presence, being too small and too settled to bother fleeing unless you get right on top of it.
Like other Tigrigobius gobies, it likely holds a small territory on the reef surface rather than roaming, which is why the same perch can be worth checking on repeat dives at a site.
No clear season shows up in the sighting data, and with water sitting between 27.1 and 28.3C year-round on these reefs, there's no thermal reason for it to disappear seasonally. Plan around Caribbean dive conditions generally rather than a specific month.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Most reliably logged in the Cayman Islands, especially around Cayman Brac and Grand Cayman, with a second strong population at Saba's Tent Reef and The Pinnacles. Little Cayman turns up sightings too, but in smaller numbers than Cayman Brac.
Mapping where Orangesided Goby is logged…
The Cayman Islands are the strongest bet, particularly Cayman Brac and Grand Cayman, with Little Cayman also producing sightings. Saba's Tent Reef and The Pinnacles are the other reliable spot outside the Caymans.
There's no detected season, and the water stays a steady 27 to 28C on these reefs year-round, so sightings aren't tied to a particular month.
Look for a near-transparent body barely a centimetre long with an orange stripe or patch along the flanks, perched still on rubble or coral rather than swimming freely. Its size and stillness are as much a clue as its colour.
About 1 cm, making it one of the smallest reef fish you'll try to photograph on a Caribbean dive.
No. It's a tiny, harmless reef goby with no sting, bite, or venom relevant to divers.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Slender Goby
803 sites
