Lethrinus laticaudis, the grass emperor, blue-lined emperor, blue-spotted emperor, brown kelp-fish, brown morwong, brown sweetlip, coral bream, grass sweetlip, grey sweetlip, piggy, red throat, red-finned emperor, snapper bream, squire, sweet-lips or tricky snapper, is a species of marine ray-finned fish belonging to the family Lethrinidae, the emperors and emperor breams. This fish is found in the eastern Indian and western Pacific Oceans.

Taxonomy Lethrinus laticaudis was first formally described in 1877 by the Australian naturalists Haynes Gibbes Alleyne and William John Macleay with its type locality given as the Percy Islands off Queensland. The correct name for this species has caused some amount of confusion in recent literature, it has sometimes been called Lethrinus fraenatus, which is a junior synonym of Lethrinus nebulosus, and at other times the name Lethrinus fletus , a junior synonym of this species, has been applied. Some authors place the genus Lethrinus in the monotypic subfamily Lethrininae, with all the other genera of Lethrinidae placed in the Monotaxinae, however, the 5th edition of Fishes of the World does not recognise the subfamilies traditionally accepted within the family Lethrinidae as valid. The family Lethrinidae is classified by the 5th edition of Fishes of the World as belonging to the order Spariformes.

Etymology Lethrinus laticaudis has the specific name laticaudis which is a compound of latus, meaning "broad", and cauda, which means "tail". Alleyne and Macleay described its tail as "emarginated, wide-spread".

Description Lethrinus laticaudus has 10 spines and 9 soft rays supporting its dorsal fin while the anal fin has 3 spines and 8 soft rays. There are no scales on the cheeks but the axilla of the pectoral fin is densely scaled.