Relationship between morphology, dispersal and habitat distribution in three species of Libellula (Odonata: Anisoptera)

摘要

Morphology is an important determinant of flight performance and can shape species' dispersal behaviour. This study contrasted the morphology of flight-related structures in dragonfly species with different dispersal behaviours to gain insights into the relationship between morphology and dispersal behaviour. Specifically, wing size, wing shape and thorax size were compared in three co-occurring species from different clades within the genus Libellula (Odonata: Anisoptera: Libellulidae) to assess howthese morphological traits are related to differences in dispersal behaviour and to how broadly their larvae occur across a habitat gradient. Two species had broad larval habitat distributions as well as high rates and distances of dispersal. These twospecies had relatively larger wings and thoraces than the third species, which was found only in permanent lakes and had limited dispersal. The hind-wings of more dispersive species also had lower aspect ratios and a relatively wider basal portion of thewing than the less dispersive species. Broad hind-wings may facilitate the use of gliding flight and reduce the energetic costs of dispersal. Determining the morphological traits associated with alternative dispersal behaviours may be a useful tool to assess the differential dispersal capacities of species or populations.