Taxonomia de imaturos de gênero Casignetus Macleay, 1819 (Coleoptera, Lucanidae, Lucaninae)

Abstract

Lucanidae are among the most primitive coleoptera and has five subfamilies, with two recorded in Brazil: Syndesinae and Lucaninae, represented by Sclerostomini, Brasilucanini and Casignetini, this latter represented by the Australian genus Eucarteria Lea, 1914 with two species, and by the South American genus Casignetus MacLeay, 1819 represented by three species: Casignetus humboldti (Gyllenhal, 1817), C. spixi (Perty, 1830) and C. lindei (Boileau, 1899). Casignetus in Brazil is recorded only for the South and Southeast regions, in the Atlantic Forest, and often high altitudes. Although the three species have already been reviewed and redescribed, only immatures of C. spixi are described. This work aimed to describe the immatures of Casignetus, providing comparative illustrations and presenting an identification key of immatures of the genus. Casignetus larvae can be recognized by the shape of pars stridens, and also by the fusion between the femur and trochanter in prothoracic and mesothoracic legs. To improve the identification of Casignetus species, new characters are proposed: curvature of frontal branches, epicranial bristles, disposition of epipharynx and hypopharynx bristles, number and arrangement of the estridulatory teeth on legs.