The effect of copulation and presence of predators on territorial behaviour of male Calopteryx haemorrhoidalis (in southern France) and of male C. splendens splendens (in northern Germany) was studied in nature. A male obtaining a copulation early in the day often secured more copulations later that day than did males not obtaining an early copulation….
The post-copulatory behaviour of Calopteryx splendens females was studied under field and laboratory conditions. After termination of copulation females usually perch and bend the abdomen so that its apex touches the ground (post-copulatory posture). The post-copulatory posture is a consequence of sperm removal by males. Male and female microstructures (spines and scales) interact to move…
Body temperature regulation and behavioral responses to temperature variation in the field were investigated in Sympetrum vicinum, a common North American libellulid that is most abundant as a mature adult in autumn. Because of its late flight season, this species is faced regularly with cooler environmental temperatures than most dragonflies investigated heretofore. By virtue of…