Pycnochromis delta
A small damselfish rarely logged outside Fiji's Lomaiviti region, seen in warm 23-28C water on deep-leaning reef.
A small, slender damselfish topping out around 5 cm, with a streamlined body built for hovering just off the reef rather than darting into cover. Look for the plain, understated colouring typical of deep-leaning chromis species rather than the bold bars or eyespots seen on shallow reef damsels. Its small size and habit of holding station just above coral structure are the main underwater cues, since fine colour detail is easily washed out by depth and distance.
Divers log this one as uncommon, so expect a brief, quiet encounter rather than a guaranteed sighting. Like other reef-associated chromis, it likely hovers in loose formation just off the reef structure, feeding on drifting plankton in the water column rather than picking at the substrate. It shows no particular reaction to divers reported in the data, consistent with a small, unbothered plankton-feeder going about its business.
Chromis species in general feed by picking plankton straight out of open water above the reef, which is why you'll often see them hanging in a loose cloud just off a wall or slope rather than sitting tight against coral.
Sighting data doesn't show a clear season, and the observed temperature range of 23.4 to 28.3C spans Fiji's water temperatures for most of the year, so it's reasonable to treat this as a year-round possibility rather than a seasonal target.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
The only confirmed sightings logged so far come from Lomaiviti in Fiji, making it the one place divers have actually recorded this species. It's not been reported at other sites in the current data, so if you want a real shot at it, Fiji's Lomaiviti region is currently the place to look.
Mapping where Deep-reef Chromis is logged…
The only region with confirmed sightings so far is Lomaiviti in Fiji. It hasn't turned up in dive logs elsewhere yet, so Fiji is currently the best bet for a sighting.
There's no clear seasonal pattern in the sighting data. Water temperatures where it's been recorded, 23.4 to 28.3C, hold for much of the year in Fiji, so it's best treated as a year-round possibility rather than tied to a specific month.
They're small, typically around 5 cm, in line with most damselfish in the chromis group. That small size and slender build are part of what makes them easy to overlook on a reef.
Look for a small, slim-bodied damselfish around 5 cm, holding position just off reef structure rather than darting into crevices. It lacks the bold bars or bright markings of shallow-reef damsels, so size, shape and hovering behaviour are your best clues.
No. It poses no threat to divers and simply goes about feeding on plankton in the water column.
Like other chromis, it likely feeds by plucking plankton directly from open water rather than grazing the reef, which is why sightings tend to be of a fish hovering just off the structure rather than nosing around coral.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
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