Species of Aphis inhabiting European Oenothera: their biology, morphology and systematics (Hemiptera: Aphididae)

Abstract

AbstractInformation on the Aphis species that feed on evening primroses (Oenothera spp.) has been summarized in the catalogue of the aphid species inhabiting herbaceous plants of the world (Blackman & Eastop, 2006). Recent descriptions of the European species, A. holoenotherae (Rakauskas, 2007), that appeared to be a sibling of the American A. oenotherae, demonstrated the need of reexamining the current state of knowledge of the Aphis species inhabiting evening primroses in Europe. The present study, based on published original data, revealed nine aphid species of the genus Aphis which are capable of living on Oenothera plants in Europe. Only two of them are really dependent on Oenothera species during their life cycle: A. oenotherae Oestlund and A. holoenotherae Rakauskas. They have different life cycles and host plant spectrum, although they are very close in their morphology. Processus terminalis length appeared to be the most reliable morphological character in distinguishing between apterous and alate viviparous females, and males of A. oenotherae and A. holoenotherae at the present time. A. grossulariae is not a typical Oenothera-feeder in Europe, occurring on evening primroses only by chance. Other Aphis species (epilobiaria, fabae, sambuci, praeterita, frangulae, nasturtii), are opportunistic inhabitants of Oenothera plants. Information about host specificity and morphology of the Oenothera-inhabiting European Aphis species is summarized, and a key for the entire range of species found living on European Oenothera is provided.