Differences in size and energy content affect the territorial status and mating success of a neotropical dragonfly

Abstract

AbstractIn male odonates, both size and fat content are related to territory defence and mating success. Males that are larger and have higher energy reserves win relatively more disputes for territory and attract more females. Wing colour has also been regarded as a mechanism that influences agonistic behaviour between males, as wing pigmentation might be regarded as a sign of male quality. In this study, we analysed whether a set of male physical (body size and wing colour), physiological (body fat content) and behavioural (disputes between males) characteristics were involved in the territory defence and mating behaviour of the neotropical dragonfly Zenithoptera lanei Santos, 1941 (Anisoptera: Libellulidae). Males were characterised as territorial whenever they warded‐off other males and remained in the same place within the pond for two consecutive days. In general, these territorial males were larger and had more abdominal and thoracic fat, engaged in pursuits more frequently, spent more time on sexual behaviour and female guarding, and mated more in comparison to subordinate males. By evaluating whether the percentage of wing area covered by black ink influenced male behaviour, we found that territorial males tended to act aggressively towards other males whose wings were partially painted, and sexually towards females irrespective of wing area painted. In Z. lanei, both body size and fat content play a role in defining territoriality. By subduing competitors and dominating preferred locations within high‐quality sites, these males are likely to be visited by females and engage in mating.