Scape strongly swollen at its base, forming a rounded lobe at the proximal zone of the scape. Colour black. Whole body dull. Propodeum angulose, sometimes forming spines. Monomorphic

Scape cylindrical, getting thinner to the base. If a lobe exists (structor Group), this is conspicuous and starts at the base of the scape, continuing the scape profile in a more or less triangular lobe. Monomorphic or polimorphic. Propodeum with various shapes

lobicornis Group (Messor lobicornis)

aegyptiacus Group (Messor bouvieri, Messor celiae, Messor hispanicus, Messor lusitanicus, Messor marocanus, Messor timidus); barbarus Group (Messor barbarus, Messor capitatus); structor Group (Messor structor)