ALLOMETRY IN SEXUAL DIMORPHISM OF STENOTARSUS-ROTUNDUS ARROW (COLEOPTERA, ENDOMYCHIDAE)

Sexual differences in several morphometric variables were analysed in diapausing Stenotarsus rotundus Arrows in order to assess the allometr ic nature of these differences and to help to determine the sex of the living beetles. The weight-length relationship is based on an allomet ric equation with an exponent near 2.6. An original method for constru cting histograms was devised to show non-normal weight distribution. T he greatest differences between sexes were found in the shape and leng th of the fifth abdominal sternite and in the width of the hind trocha nter, which is correlated with differences in size of the trochanteral tooth occurring in males. Sexual differences are more conspicuous in larger individuals, a phenomenon which is described by different allom etric equations for the sexes.