Size variation with elevation in adults and larvae of some Venezuelan stoneflies (Insecta: Plecoptera: Perlidae)

Abstract

The objective of this study was to determine the relationship between body size and elevation in adults and larvae of five species of plecopterans of the genus Anacroneuria inhabiting the Chama River watershed (Mérida State, Venezuela). Body size was determined by six morphometric variables in adults (body length, head capsule width and length, forewing length, pronotum width and length) and eight in larvae (body length, head capsule width and length, intraocular distance, forewing pad, first abdominal segment length and width and total abdomen length). However, only forewing length and head capsule length showed a positive significant correlation in all adults and larvae, respectively, even though correlation coefficients in larvae were lower than in adults. A tendency to sex differences was also noted in adults with greater forewing length in females.