Looks can be deceiving: a possible novel mimicry assemblage in Cerambycidae (Coleoptera), with phylogeny and new species of firefly-like Hemilophini

Hemilophini Thomson, 1868 is a tribe in the subfamily Lamiinae (Cerambycidae) comprising 582 extant species and 131 genera. Beetles in this tribe are remarkable for their coloration patterns, which resemble those of other beetle families such as Lampyridae and Lycidae, 2 groups recognizable for their chemical defenses—suggesting cases of Batesian mimicry. Within Hemilophini, the genera Itumbiara Martins & Galileo, 1992 and Pyrobolus Chevrolat, 1838 include species that exhibit firefly-like forms. These genera share several diagnostic features, resulting in poorly defined boundaries between them, and further obfuscating their generic limits is the lack of phylogenetic studies evaluating their monophyly. In order to redefine these genera, we performed the first phylogenetic analyses, employing morphological and molecular data. The molecular analyses included mitochondrial (Cox1) and nuclear (28S and CAD) markers. Molecular phylogenies were reconstructed with both Bayesian and maximum likelihood inference methods. The morphological phylogeny was reconstructed using a matrix of 51 characters based on external morphology and male terminalia, analyzed through parsimony. The phylogenetic hypotheses revealed Itumbiara and Pyrobolus as polyphyletic groups, and new combinations were proposed. Moreover, we report a novel field observation of an assemblage between Cerambycidae and Lampyridae, 14 new distributional records are provided, and 4 new species are described: Pyrobolus fernandoi sp. nov., Pyrobolus monnei sp. nov., Pyrobolus piliventris sp. nov., and Pyrobolus praestigiosus sp. nov.; and Adesmus acanga Galileo & Martins, 1999 is defined as a junior synonym of Pyrobolus rectilineus (Bates, 1881). Finally, the hypothesized Batesian mimicry and evolutionary convergence in these genera are discussed.