Megacheira ("Great Hands") is an extinct class of predatory
arthropods that possessed a pair of short
enlarged appendages (the source of the class' name). They strongly resemble early
chelicerates. Most of them were found in marine environments throughout the world from the lower to middle
Cambrian. The group might also contain one species (
Enalikter aphson) described from the
Silurian Herefordshire Lagerstätte of the
United Kingdom, and one species (
Bundenbachiellus giganteus) known from the Early
Devonian of
Germany; however, the interpretation of these taxa as megacheirans was challenged by Struck
et al. (2015). Megacheirans were important components of several faunas, including the
Burgess,
Wheeler and
Maotianshan Shales Lagerstatten. Genera referred to the class include
Leanchoilia,
Alalcomenaeus,
Oestokerkus,
Yohoia,
Fortiforceps and
Jianfengia.