Revisiting Lamprosoma and expanding knowledge of Lychnophaes (Coleoptera: Chrysomelidae, Lamprosomatinae): Molecular phylogeny, new species, host plants, associated parasitoid wasps and geographical records

Abstract

Lamprosomatinae comprises ~ 250 species in 14 genera and four tribes, yet several Neotropical lineages remain poorly defined due to the absence of comprehensive morphological and molecular assessments. This study provides an integrative taxonomic reassessment of the closely related genera Dorisina, Lamprosoma, and Lychnophaes, including the description of two new species from Brazil. External and internal morphological characters of both sexes are documented with light and scanning electron microscopy, and updated biological information is presented, including host plant records, a newly documented parasitoid association, and distributional data.

We also include observations on immatures and natural history traits. The first molecular dataset focused on Neotropical Lamprosomatinae is incorporated to evaluate generic limits and test the monophyly of the focal taxa. Our analyses reveal new insights into tribal-level relationships within Cryptocephalinae, supporting Fulcidacini + Pachybrachini and Clytrini + Cryptocephalini, while Mylassini forms a polytomy with the remaining groups.

The monophyly of Lychnophaes could not be confirmed, as it is represented only by Lychnophaes imbirucu sp. nov. Conversely, Lamprosoma is recovered as monophyletic, with Lamprosoma cambuci sp. nov. clustering with two additional unidentified congeners. These results corroborate the relationships proposed by Chamorro and Konstantinov based on morphological data and reinforce the synapomorphies established for the tribe.