ELECTROPHORETIC VARIATION IN THE PARTHENOGENETIC GRASSHOPPER <i>WARRAMABA VIRGO</i> AND ITS SEXUAL RELATIVES

Abstract

Allozyme variation was examined within and between parthenogenetic clones of Warramabo virgo and the sexual ancestors, undescribed species P196 and P169. Both sexual species can be separated into northern and southern races using six loci, and the separate hybrid origin for the two major groups of parthenogenetic clones (the Standard Phylad and the Boulder-Zanthus Phylad) is substantiated by the racial variation in the sexual ancestors. Heterozygosity values in the parthenogenetic species are 6-9 times higher than those in the sexual species, and there is evidence for the accumulation of new variation subsequent to the hybrid origin of both phylads. The new variation is the result of either new mutations, recombination, or both. Three loci in the Standard Phylad clones reveal "orphan" alleles not found in the sexual ancestors; these alleles probably arose subsequent to hybridization but prior to the dispersal of the parthenogenetic clones. These data, in combination with those from other genetic studies, suggest that new variation may arise as a consequence of hybridization. Collectively, the allozyme, chromosome, molecular, and morphological data suggest that the Standard Phylad clones are of a more ancient but restricted origin, with clonal variation being the result of multiple hybridizations between individuals of P196 and P169.