Sphaeramia orbicularis
Small, round-bodied cardinalfish common in Malaysia's east coast, Palau and Raja Ampat, hovering near reef structure in 26-29 C water.
A small, almost egg-shaped fish about 7 cm long, with a compressed, deep-bodied silhouette unlike the slimmer torpedo shape of most cardinalfish. Look for a pale silvery-tan body scattered with fine dark speckles, a dark bar or blotch through the eye, and a dusting of small black spots across the rear half of the body and tail base. It hangs almost motionless in small groups rather than darting about, which makes the spotting pattern easy to check at close range.
Divers usually find it hovering in loose, static groups just above or tucked among coral heads, sponges, or mangrove roots, barely moving except to hold position against gentle current. It's unbothered by divers at normal distance and won't scatter unless you get right up close, making it an easy fish to photograph slowly. Most sightings are on shallow, sheltered reef sections rather than open water or deep drop-offs.
Like other cardinalfish, it's a mouth-brooder: males carry the fertilised eggs in their mouth until the young are ready to fend for themselves, so the small groups you see hovering together are often a mix of ages from the same brood site.
No clear seasonal pattern shows up in the sightings, and with a comfortable range of 26.3 to 29.3 C on the reefs where it's found, it's a year-round encounter rather than a seasonal one.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Most reliably logged along Peninsular Malaysia's east coast and around Sabah, with strong numbers also in Koror & Malakal and the Rock Islands in Palau. It also turns up widely through Indonesia (Java, Raja Ampat) and the Philippines (Visayas, Palawan), usually as an uncommon but steady find rather than a headline sighting.
Mapping where Orbiculate Cardinalfish is logged…
They're most consistently seen along Malaysia's east coast and around Sabah, in Palau's Koror & Malakal and Rock Islands, and across Indonesia and the Philippines, including Java, Raja Ampat, Visayas and Palawan.
There's no strong season in the sighting data. They sit in warm 26 to 29 C water year-round, so any month on a tropical reef trip works.
Look for a small, rounded, deep-bodied fish around 7 cm with a silvery-tan body, fine dark speckling, and a dark eye bar. They hang in still, loose groups near reef structure rather than swimming actively.
They're a small reef fish, typically reaching around 7 cm in length, which keeps them tucked close to shelter rather than out in open water.
Males are mouth-brooders, holding fertilised eggs in their mouth until the young hatch, which is why you often spot them in small, tight-knit groups near the same patch of reef.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Iridescent Cardinalfish
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