Lutjanus russellii
Uncommon but steady on reefs from Queensland to Koh Chang, Moses Snapper cruises 24-29C water year-round. Here's how to spot one.
Grows to around 35 cm, with a deep-bodied, slightly compressed shape typical of snappers and a silvery to yellowish-grey body that catches light on a reef. The main giveaway is a dark blotch sitting high on the flank just behind the gill cover, often with faint yellow stripes running along the body. Fins are typically yellowish, and the profile is more rounded than sharklike, making it easy to pick out once you know the shoulder mark to check.
Usually seen hanging singly or in small loose groups near reef structure, ledges, and drop-offs rather than out in open water. It tends to hold a steady position and lets divers approach reasonably close before easing off, rather than bolting. Most sightings sit in the uncommon range, so it is a fish you notice on a good number of dives without it being a guaranteed encounter.
Like most snappers it is a carnivore that feeds on smaller fish and invertebrates around reef structure, often most active as light shifts at dawn and dusk even though divers log it through the day near cover.
No clear seasonal pattern shows up in the sightings, and its comfort range of roughly 24 to 29C matches tropical and subtropical reefs year-round, so any month works at the sites where it is known.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Most reliably logged in Australia, especially Queensland and New South Wales, where it turns up across a wide spread of reef sites. Outside Australia it is a steady find in Thailand around Koh Chang and Koh Tao, and shows up with some consistency in Taiwan's Longdong, Vietnam's Nha Trang, and Hong Kong's Sai Kung.
Mapping where Moses Snapper is logged…
Queensland and New South Wales in Australia are the strongest areas, with reliable sightings also in Koh Chang and Koh Tao in Thailand, Longdong in Taiwan, Nha Trang in Vietnam, and Sai Kung in Hong Kong.
There is no strong seasonal signal in the data, and its preferred water temperature of about 24 to 29C is common on tropical reefs year-round, so it can turn up on any dive.
Look for a silvery to yellowish-grey snapper around 35 cm with a distinct dark blotch on the upper flank just behind the gills, plus faint yellow body stripes and yellowish fins.
They typically reach around 35 cm in length, a mid-sized reef snapper rather than one of the larger species in the family.
No, they are not considered dangerous to divers and generally hold near reef structure without showing aggression toward people in the water.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Emperor
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