Functional anatomy of the secondary copulatory apparatus of the male dragonfly Tramea virginia (Odonata: Anisoptera).

Abstract

In the dragonfly Tramea virginia, the secondary copularoty apparatus (SCA) on the venter of the second and third abdominal segments consists of the anterior and posterior laminae, a pair of gential lobes and hamules, the ligula, genital fossa, supporting frame work, and the four segmented, highly specialized penis. The penis head represnts the distal or fourth segment of the penis and bears paired lateral and apical lobes and a medial process. The medial process includes a sperm reservior, a short sperm tube, and paired cornua and inner lobes. The sperm reservoir opens into the sperm tube which bears a terminal orifice between the inner lobes. Gross morphology of the SCA of T. virginia is similar to that of other libellulids except that the gential lobes and hamules are comparatively large in size, the ligula is triangular in shape with an apical flat rectangular lobe and stiff basal setae, the penis bears a pair of cuticular denticles below the spur of the second segment, the apical lobes are inflatable without spines and bristles, and the cornua with smooth outer and spiny inner surface collectively signifying the species-specific anatomical features and the functional specialization for sperm transfer and removal. © 1993 Wiley-Liss, Inc.