Félix, SandraSoares, António O.2011-01-182011-01-182003FÉLIX, S. & A. O. SOARES, (2003). Intraguild predation among the aphidophagous ladybird beetles Harmonia axyridis Pallas and Coccinella undecimpunctata L. (Coleoptera: Coccinellidae): characterization of the direction and symmetry. “Arquipélago. Life and Marine Sciences”, Supl. 5: 103-106.http://hdl.handle.net/10400.3/822Proceedings of the 8th International Symposium on Ecology of Aphidophaga: Biology, Ecology and Behaviour of Aphidophagous Insects.Direction and symmetry of intraguild predation (IGP) between all developmental stages of the aphidophagous Harmonia axyridis Pallas and Coccinella undecimpunctata L. were characterized. Our results revealed that H. axyridis predation level was significantly higher than C. undecimpunctata and eggs were the more vulnerable developmental stage. Significantly asymmetric IGP on eggs occurred after the second and fourth larval stages of H. axyridis and C.undecimpunctata, respectively. Asymmetric IGP on pupas exclusively occurred in the presence of the fourth larval stage of H. axyridis.engAphidophagous ladybird beetlesCoccinella undecimpunctata L.Direction and SymmetryIntraguild PredationHarmonia axyridis PALLASjournal article