title: A comparative study of the proventricular structure in corbiculate apinae (Hymenoptera, Apidae).
abstract: The present study compares the proventricular structure, analyzed under scanning electronic microscope (SEM), among tribes of corbiculate Apinae. Fifty-one species of stingless bees (Meliponini), one species of honeybee (Apini), three species of bumblebees (Bombini) and seven species of orchid bees (Euglossini), were analyzed as in-group, and one species of sphecid wasp (Sphecidae) and two species of Halictidae bees, as out-groups. The proventricular bulb presents a basic morphology pattern similar to that of other Hymenoptera such as ants and wasps, being a symplesiomorphy for bees. The shape of proventricular folds constitutes a synapomorphy for Meliponini and an autapomorphy for Apini. The shape of hair-like projections of the cuticle that lines the proventriculus is a synapomorphy for Meliponini and Apini. These proventricular data corroborate the monophyly of the tribe Meliponini and the hypothesis that recognizes only one tribe for stingless bees. In addition, Meliponini+Apini constitutes a monophyletic group and Bombini+Euglossini another monophyletic group. The results confirm that internal morphology is a character that can be used in studies of the phylogeny in insects and the use of SEM as a powerful tool in these analyses.
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Viçosa, 36571-000 Viçosa, MG, Brazil. jeserrao@mail.ufv.br
authors.forename: J E
authors.initials: JE
authors.lastname: Serrão
mesh_terms: D000818:Animals; D001516:Bees / Q000145:classification* / Q000648:ultrastructure*; D004064:Digestive System / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D010802:Phylogeny; D014863:Wasps / Q000145:classification / Q000648:ultrastructure