Systematics of the New World Rostrate Genus Metaxyphloeus Thomas, 1984 (Coleoptera: Laemophloeidae): Morphological Evidence for Monophyly Supporting a Broader Generic Concept

A morphology‐based MP analysis is undertaken to test the monophyly of the lined flat bark beetle genus Metaxyphloeus Thomas, 1984, as well as to hypothesize its intra‐ and intergeneric evolutionary relationships. Based on the results of the present work, Metaxyphloeus , as currently composed, is hypothesized as a monophyletic assemblage of rostrate laemophloeids, whose definition is adjusted hereby to include two previously unknown, earliest diverging lineages. A taxonomic treatment is provided for all known species of the genus, which are diagnosed and illustrated in fine detail, including the mouthparts and genital structures. In addition, three further species are proposed as new: M. brevirostris sp. nov. , M . dorsocapillatus sp. nov., and M . homalirhinoides sp. nov. Biological information constitutes rare direct evidence for mycophagy among members of Metaxyphloeus , which may also serve as vectors for the dispersion of fungal conidia and spores (endozoochory). Finally, a key to the species of Metaxyphloeus is provided, and their distributions are synthetized in maps.