Emblemariopsis bottomei
A 2cm speck on Bonaire's reefs, most reliably logged along the Leeward Coast in warm 25-30C water year-round.
Barely 2cm long, this is a slender, dark-bodied fish that reads almost black against pale coral rubble or sponge, with a blunt head and large eyes typical of blennies in this family. It perches upright on its pelvic fins rather than swimming freely, tucked into small holes or crevices, so divers usually spot it as a motionless dark comma rather than a moving fish. No strong colour pattern to key on, size and posture are the giveaway.
Look for it perched motionless on coral rubble, sponge, or reef debris rather than swimming in open water, tucked close to a hole it can dart into if disturbed. It is an uncommon sighting even at the sites where it turns up, so this is one for divers who slow down and scan small structure closely rather than cruise past. Most reports come from the shallower reef and rubble zones typical of Bonaire's fringing reef dives.
At only 2cm long it is easy to swim straight past, and most sightings on record come from divers who were specifically scanning rubble and small crevices rather than the open reef.
Recorded water temperatures run a comfortable 24.6 to 30.6C, and there is no detectable seasonal pattern in the sightings, so it is a year-round find rather than a seasonal one.
Every logged sighting so far comes from Bonaire, making it effectively a Bonaire specialty among divers who log this species. The Leeward Coast holds the strongest run of sites, with the East Coast of Bonaire also producing sightings, so working sheltered rubble and reef-wall sites on the leeward side gives the best odds.
Mapping where Midnight Blenny is logged…
Bonaire is the only place with confirmed sightings so far, particularly along the Leeward Coast and, to a lesser extent, the East Coast. It has not been reliably logged elsewhere.
There is no clear season. Water temperatures at the sites where it is found stay between about 24.6 and 30.6C year-round, so it can turn up on any dive month.
Look for a tiny, dark, slender fish only about 2cm long, perched still on rubble or sponge rather than swimming. It lacks bright markings, so size, dark colouring, and its habit of staying put in a crevice are the main clues.
They stay tiny, topping out around 2cm, which is roughly the length of a fingernail. This makes them one of the smaller reef fish a diver is likely to try to spot.
No. They pose no risk to divers and are far more likely to hide from you than react to your presence.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Yellowtail Clownfish
3,523 sites
