Morfologia comparada das peças bucais de vespas dos gêneros filogeneticamente basais em polistinae (hymenoptera: vespidae).

Abstract

Most of the studies related to Neotropical social wasps deal with their behavior. However, important aspects of the biology of Polistinae such as nest construction and individual defense are partly a product of the function of mouthpart structures. In addition, as in other insects, mouthparts are related to nutrition. In view of this importance, we sought here to describe patterns of variation in the shape of the stipe and maxillary galea among species of the subfamily Polistinae, from phylogenetically basal genera (Polistes, Mischocyttarus, Apoica, Angiopolybia, and Age/aia). Specimens from twelve species were prepared in KOH solution for relaxation of the musculature. The stipe and maxillary galea were removed with tweezers and placed in a Petri dish with ethyl alcohol for character analysis, measurement with a micrometer lens, and drawing under a clear camera. The analyses showed a reasonable diversity of shapes in the two structures studied among genera and species. In the style, variation was found in the amount and arrangement of bristles, the shape of the medial and lateral margins, the internal cavity, and the medial and lateral flaps. In the galea, variation was found in the amount and arrangement of bristles, morphology of the margins, internal concavity, and medial, lateral and distal flaps. Despite the diversity of forms, the differences are small, allowing us to infer that they do not imply functional differences between genera and species. However, they may be important for systematic studies.