Fishes · Bony fishes · Lefteye flounders

Largetooth Flounder

Pseudorhombus arsius (Hamilton, 1822)

syn. Neorhombus occellatus, Neorhombus ocellatus, Pleuronectes arsius, Pleuronectes mortoniensis, Pseudorhombus andersoni, Pseudorhombus arius +5 more

up to 40 cm800 g0-200 mLeast Concern

A flounder of up to 40 cm with both eyes on the left side and a mouth that is large for a flatfish, armed with the canine teeth that give it its name. The eyed side is mottled brown, usually with a pair of darker blotches along the lateral line, and matches the sand it lies on closely enough that the fish is normally seen only when it moves. It prefers sheltered water - protected bays and lagoons with a shallow sand bottom - rather than the open reef, and takes small fish and crustaceans in a short rush from a standing start. Ranges from the 🌊 Red Sea east to 🇫🇯 Fiji and 🇯🇵 Japan.

The genus. Pseudorhombus Bleeker 1862 - pseudo- (false). ETYFish

The species. Pseudorhombus arsius (Hamilton 1822) - A local name for this fish. ETYFish

How to recognise it

large mouth with visible canine teeth
mottled brown with darker blotches along the lateral line
both eyes on the left side

Why it's threatened

Major threats are unknown. Although not targeted, it is taken in demersal fisheries, the impacts of which have not been quantified across its distribution. Larger flatfishes are likely to be susceptible to declines due to overexploitation. For example, in the Gulf of Thailand, demersal trawling ultimately led to significant declines in the overall abundance of flatfishes by the 1980s, including members of the Paralichthyidae (Pauly 1994). In contrast, this species appeared to increase in abundance after a trawl fishery began in the Gulf of Carpentaria, Northern Australia (Harris and Poiner 1991). Recent data, especially for individual species, are unavailable concerning the status of flatfish populations throughout the Indo-Pacific region.

Threat classification from the IUCN Red List.

Affiliate partner

Quick facts

GroupLefteye flounders

Max sizeup to 40 cm

Max weight800 g

Depth0-200 m

DietCarnivore

HabitatShallow sand in bays and lagoons

RarityCommon

Conservation status

Least Concern