Immune melanization ability and male territorial status in Erythemis vesiculosa (Fabricius) (Anisoptera:Libellulidae)

Using a nylon filament implant inserted in the thorax, it was tested whether there were immune ability and size differences between territorial and nonterritorial ♂ ♂ that gather in lentic aquatic sites. It was found that territorial ♂ ♂ mounted a larger melanin-based immune response than nonterritorial ♂ ♂. This is coherent with current results in other odon. and is interpreted as territorial ♂ ♂ being in better condition than nonterritorial ♂ ♂. However, there was no size difference between the territorial and nonterritorial inidividuals. This suggests that size may be a poor predictor of immune ability.