Cytogenetics of the cultrata group of morabine grasshoppers I.A group of species with XY and X1X2Y sex chromosome mechanisms

Abstract

Two closely related species belonging to the cultrata group show an XY condition in the male as a result of an X-autosome fusion. One of these has two cytological races which differ in the shape of the Y chromosome. This complex of XY forms has given rise to an XlX2Y species by a further Y-autosome fusion. The latter species has two cytological races which differ in the shape of the Y and X2 chromosomes, presumably as a result of the fixation of pericentric inversions and other structural changes.