Wood-Mason, 1875
All pereiopods, or at least the first four, with true chelae. First pair of pereiopods long and slender, more than twice as long as the second pair. Carapace flattened. Eyes immovable, not protruding above surface of carapace, and without pigment. Tail-fan entirely calcified and with telson triangular, pointed.
This family has several genera and numerous species. All species inhabit the deep sea and none are of commercial value. Although some of them attain good sizes, they seem to have relatively little meat and for that reason are of no economic interest. However, some species can be caught in considerable quantities. During the 1964 cruises of R.V. JOHN ELLIOT PILLSBURY the catch of Stereomastis sculpta talismani (Bouvier, 1917), at one of the stations off West Africa, was so large that most of it had to be shoveled overboard.
Notwithstanding all this, none of the numerous (more than 35) species appears ever to have been brought to the fish markets, or sold as food or bait. Therefore this group is not further considered here. The taxonomy of the Polychelidae, especially of the generic level, is still very unsettled.