Cytological studies were made on larvae of Gigantodax marginalis, G.
chilensis, G. fulvescens and Cnesia dissimilis from four creeks
in Lanin National Park, Neuquen province, Argentina. Chromosome maps and
idiograms of these species are presented. The following inversions were
observed: G. marginalis: IL-1 (X-linked inversion), IL-2 (Y-linked
inversion), IIS-1.2, IIL-1, IIIL-4,5; G. chilensis: IL-4 (X-linked
inversion), IIS-1.2, IIIL-4,5; G. fulvescens:IL-1 (X-linked
inversion), IL-3 (Y-linked inversion), IIS-1.2, IIL-1, IIIL-4,5; C.
dissimilis: IL-1, IL-5, IIIL-1. Karyological information was used to
construct a cladogram and Cnesia sp. Was found to show close
resemblance to the three Gigantodax spp.