An examination of competitive gametic isolation mechanisms between the damselflies Ischnura graellsii and I. elegans

Recent findings suggest that postmating prezygotic isolation (i.e. gametic barriers) could be an important factor preventing hybrid formation. Competitive gametic barriers emerge when a female is inseminated by a conspecific and a heterospecific male. We examined whether sperm proportions after double matings and copulation duration impede hybrid formation. For this, we used females of Ischnura…

Odonata communities in retrodunal ponds: a comparison of sampling methods

Dragonflies are commonly used as indicators of environmental quality and different methods have been employed to monitor odonate assemblages, such as surveys of all adults, evaluations based on breeding adults, sampling of larvae and collection of exuviae. Results obtained with different sampling methods may not be interchangeable, as the different life stages (e.g. larvae, adults)…

Odonata biodiversity of the Argentine Chaco biome

Odonates of small temporary pools, marshes, large permanent ponds, oxbow lakes, dams, and perennial rivers were sampled in the semiarid Chaco biome of NW Argentina between September 2007 and December 2008. Information from 35 localities yielded 60 species; presence/absence information of species was recorded in a spatial-relational database. Alpha, beta, and gamma diversity and total…

Libellago corbeti sp. nov. from Sri Lanka (Odonata: Chlorocyphidae)

Libellago corbeti sp. nov. (holotype ♂: Sri Lanka, Ratnapura District, near Kudawe, 6.26°N, 80.25°E, 03 vii 2007, to be deposited in the Sri Lanka National Museum, Colombo) is described and figured. Its phenotype does not resemble that of any other Libellago species. Habitat characteristics and species behaviour are briefly outlined. Keys to males and females…