Morphology of male and female genitalia in Sympetrum danae (Sulzer), with special reference to the mechanism of sperm removal during copulation (Anisoptera: Libellulidae)

The female genitalia are characterized by a spherical bursa copulatrix and 2 separate, narrow spermathecae. The fourth segment of the penis is characterized by 2 long cornua, 2 inflatable inner lobes, 2 flap-like lateral lobes and a tube-like apical lobe. Sperm remains were found on most parts of the penis of individuals from interrupted copulas, especially on the apical and inner lobes. — Observations of copulatory movement, supplemented by a reconstruction of the coitus, suggest that sperm may be removed and ejaculated during a single type of movement, throughout the major part of copulation.