摘要：Delphacodes kuscheli (Hemiptera: Delphacidae) is a vector of the ethiologic agent of the Río Cuarto Disease (RCD). This viral disease accounts for the most important production losses to maize due to pathogen infections. The objective of this work was to analyze the morphological variation between dispersive populations of Delphacodes kuscheli collected in different geographical regions. Insects were collected along a 500 km transect in the main maize production area of Argentina during the spring and summer of 1999 and 2000. There was no body size difference between insects collected in different places. When considering all the sampling stations, it was possible to assign the sampling station in which they were collected in the 50% of the individuals. When considering only the three sites in both extremes and middle of the transect, 75.53 and 82.05% of the individuals were correctly classified to the sampling stations from which they were collected. A very high temporal discrimination was also evident when the different years were considered. These results suggest a spatial and temporal structure of the populations and a very high phenotypic flexibility of the species. Ecological implications are discussed
