ABSTRACT
Aphids (Aphidoidea) are a part of the Hemiptera, a species-rich branch of the hemimetabolous insects (Fig. 1). Refl ected in their alternative name “Rhynchota” all members of Hemiptera have mouthparts transformed to a “sucking beak”. Mandibles and maxillae are used as stechborsten, the labium forms a sheath around them, maxillary and labial palps are reduced. This innovation initially evolved to optimize the exploitation of plant saps for feeding. The sistergroup of Hemiptera is most probably the Thysanoptera (thrips), which also suck plant saps, but their mouthparts are derived in a different way. Among the hemipteran subtaxon Heteroptera several branches secondarily switched to predatory behavior. Retaining sucking mouthparts, these bugs feed on invertebrate hemolymph or vertebrate blood.
