A comparison of the male genitalia of three Calopteryx species (Odonata: Calopterygidae)

Abstract

We compared the morphology of male genitalia in the damselflies Calopteryx maculata (P. de Beauvois), C. aequabilis Say, and C. amata Hagen in Nova Scotia. Differences were most pronounced between C. maculata and the other two species. The number of spines and the arrangement and density of spinulae on the ventrolateral surface of the penis shaft varied among species; the largest species, C. amata, had three times as many spines as did the smallest, C. maculata. Scanning electron micrographs of penes revealed structures in C. aequabilis and C. amata similar to those in C. maculata. Males of both C. amata and C. aequabilis can likely remove sperm from the reproductive storage organs of females, as previously shown in C. maculata and C. dimidiata.