Kurtosis and skew show longer males in Centrobolus

Sexual Size Dimorphism (SSD) in the diplopod genus Centrobolus has a positive correlation with body size. Length, width and rings are the main components of interspecific variation in diplopod species. Interspecific variation in size was calculated in 6 species and data sets tested for skewness and kurtosis. 28 values were positively skew and had positive kurtosis while 8 were negatively skew and 4 had negative kurtosis. In 6 cases width was positively skewed and in four cases it was negatively skewed. Length was positively skewed in all 6 species except C. titanophilus. Longer males were thought to have increased reproductive success through female preference for larger size when there was size assortative mating behaviour.