Queen polymorphism in the non-parasitic ant, Leptothorax spec. A, is most probably genetically mediated by a pair of alleles E/e. E suppresses the development of wings, thoracic structures and ocelli in female larvae. Only ee-larvae may grow to gynomorphic, winged queens, EE- and Ee- larvae develop into intermorphic, wingless queens. The
frequency of intermorphic queens varies widely in different habitats. Whereas in homogeneous coniferous forests throughout southern and central Quebec the gynomorph is abundant , in patchily distributed rocky outcrops along the St. Lawrence River intermorphic queens predominate. We suggest a different dispersal success of the two morphs in the various habitats.