Ornidia Lepeletier & Serville, 1828 (Diptera, Syrphidae) no Estado do Rio Grande do Sul, Brasil: distribuição e preferência floral

Resumo

The genus Ornidia (Diptera, Syrphidae) is represented by four described species, three of them are recorded from Brazil. Studies about this group are lacking in Rio Grande do Sul State. This work aims to document and increase the knowlegde around the distribution of the species of Ornidia in Rio Grande do Sul and the flowering plants visited by Ornidia obesa Fabricius, 1775 in Santa Cruz do Sul region. The material deposited at CESC, MCNZ, MCTP, DZUP,
MNRJ and MZSP were examined. Presently, two species of Ornidia are represented in Rio Grande do Sul State: O. obesa and O. major. O. obesa showed intra-specific differentiation for body coloring. A key to the identification of the species of Ornidia found in Rio Grande do Sul is provided. O.obesa was flower visitor of 20 plant species. The niche breadth value indicates that the O. obesa is
polilectic, without a well-defined floral preference.