We studied the infestation degree and corporal distribution of the chigger Eutrombicula alfreddugesi on the lizard Sceloporus couchii in a population of Santa Catarina, Nuevo León, México. Most lizards had acari; however, the mean number of acari for males was significantly higher than the mean for females. There was not significant relationship among the snout-vent length, weight and the total number of acari in both sexes, probably indicating that this parasite does not influence the physical condition of this lizard. The analysis of the corporal distribution showed that the region where the acari were most concentrated was in the post femoral pockets, followed by the neck region and the axillary region.
