Latreille, 1831
First pereiopod chelate of subchelate. Rostrum of diverse shapes. Epistome short, far shorter than 1/3 of the carapace. Eyes not placed on an elevation of the cephalon. Carapace without frontal horns. Antennal flagellum long, multiarticulate, flexible, whip-like.
The infraorder contains a single superfamily Thalassinoidea Latreille, 1831, with 7 families, viz., Axianassidae, Axiidae, Callianassidae, Callianideidae, Laomediidae, Thalassinidae and Upogebiidae with all together more than 350 known species. Of these 7 families only 3 are dealt with here as the other do not have species of which it is known that they are of interest to fisheries. Of these three families, Thalassinidae, Callianassidae and Upogebiidae, perhaps two or three species are used for human consumption, a number of others is used as bait for fishing.