UNE ANALYSE DES COMPLEMENTS CHROMOSOMIQUES DE CERTAINS ORTHOPTERES DU QUEBEC ET SA SIGNIFICATION TAXONOMIQUE ET EVOLUTIONNAIRE

Abstract

The chromosome numbers were determined and the complements analyzed for certain Orthoptera of Quebec, the karyology of which had not yet been studied. The taxa reported on are: Oecanthus quadripunctatus, 2n (♀) = 19; Metrioptera roeseli, 2n (♀) = 31; Amblycorypha oblongifolia, 2n (♀) = 31; Scudderia pistillata, 2n (♀) = 29; S. curvicauda, 2n (♀) = 31; S. texensis, 2n (♀) = 31; S. furcata furcata, 2n (♀) = 31; and Melanoplus punctulatus punctulatus, 2n (♀) = 23.The chromosome complement of Oecanthus quadripunctatus and that of O. nigricornis already studied by Johnson (1931) are apparently identical, but the chromosome complements of O. longicauda and O. indicus of Japan differ so much from those of the two above-mentioned North American species that the association of the American and Japanese entities with the same genus is subject to doubt.The data supplied by the karyological analysis of Metrioptera roeseli, Amblycorypha oblongifolia, Scudderia pistillata, S. curvicauda, S. texensis and S. furcata furcata corroborate the classification made on the basis of morphological characters. The origin of the karyological differences which distinguish the members of this group of Tettigonioidea is discussed.