Lutjanus monostigma

The one-spot snapper, also called the onespot seaperch or Moses snapper, is a marine fish in the family Lutjanidae. It lives across the Indo-Pacific region.

Taxonomy

French zoologist Georges Cuvier first described it in 1828 as Mesoprion monostigma, based on a specimen from the Seychelles. Its scientific name combines mono ("one") and stigma ("mark"), referring to the black spot beneath the front dorsal fin rays—prominent in juveniles but often fading in adults.

Description

This snapper has a fairly deep body, with a standard length 2.6 to 3.0 times its deepest point. Its forehead slopes gently, and the preopercular notch and knob are weak. The vomerine teeth form a crescent-shaped patch without a rear extension, and the tongue has no teeth.

The dorsal fin has 10 spines and 13–14 soft rays; the anal fin has 3 spines and 8–9 soft rays. Both the dorsal and anal fins are rounded or somewhat angular at the rear. Pectoral fins have 15–17 rays, and the tail is truncate or slightly notched.

Maximum total length is 60 cm, though 50 cm is more typical. Body color ranges from whitish to pink or grey, with yellow fins and a black spot or blotch on the rear body. As the fish matures, this spot shrinks and becomes more oblong.

Distribution and habitat

The species is widespread from the Red Sea and eastern Africa (south to Sodwana Bay, South Africa) across the Persian Gulf, Indian Ocean islands, Sri Lanka, and Southeast Asia, east to the Marquesas and Line Islands, north to Japan’s Ryukyu Islands, and south to Australia. Adults inhabit coral reef areas, often near caves and coral formations, at depths of 1 to 60 meters.

Biology

A nocturnal predator, it feeds mainly on fish and benthic crustaceans. It is usually solitary but sometimes forms small schools. Off Papua New Guinea, half of females reach sexual maturity at about 32 cm total length and 3 years old. Maximum lifespan is estimated at 13 years.

This snapper is important to commercial fisheries, especially in Oceania, where it is caught with handlines, traps, and gillnets and sold fresh. It is known to carry ciguatoxin, particularly in Tuvalu. Because it is widespread and abundant in areas with low fishing pressure, the IUCN classifies it as Least Concern.