The order Coleoptera (beetles) is arguably the most speciose group of animals, but the evolutionary history of beetles, including the impacts of plant feeding (herbivory) on beetle diversification, remain poorly understood. We inferred the phylogeny of beetles using 4,818 genes for 146 species, estimated timing and rates of beetle diversification using 89 genes for 521 species representing all major lineages and traced the evolution of beetle genes enabling symbiont-independent digestion of lignocellulose using 154 genomes or transcriptomes. Phylogenomic analyses of these uniquely comprehensive datasets resolved previously controversial beetle relationships, dated the origin of Coleoptera to the Carboniferous, and supported the codiversification of beetles and angiosperms. Moreover, plant cell wall-degrading enzymes (PCWDEs) obtained from bacteria and fungi via horizontal gene transfers may have been key to the Mesozoic diversification of herbivorous beetles—remarkably, both major independent origins of specialized herbivory in beetles coincide with the first appearances of an arsenal of PCWDEs encoded in their genomes. Furthermore, corresponding (Jurassic) diversification rate increases suggest that these novel genes triggered adaptive radiations that resulted in nearly half of all living beetle species. We propose that PCWDEs enabled efficient digestion of plant tissues, including lignocellulose in cell walls, facilitating the evolution of uniquely specialized plant-feeding habits, such as leaf mining and stem and wood boring. Beetle diversity thus appears to have resulted from multiple factors, including low extinction rates over a long evolutionary history, codiversification with angiosperms, and adaptive radiations of specialized herbivorous beetles following convergent horizontal transfers of microbial genes encoding PCWDEs.

The 1042 species of Scarabaeoidea known to occur in Peru are listed with their taxonomic placement in families, subfamilies, and tribes.

Two new endemic, brachypterous species of Passalus (Pertinax) from mid and high montane habitats of the Sierra de Talamanca, Costa Rica, are described and illustrated. Additionally, a checklist for the bess beetle species of Costa Rica is provided.

Cyclocephaline scarabs, the second largest tribe of rhinoceros beetles, are important pollinators of early‐diverging angiosperm families in the tropics. The evolutionary history of cyclocephaline genera is poorly resolved and several genera are thought to be nonmonophyletic. We assess the monophyly of Mimeoma C asey, a group of N eotropical palm‐feeding scarabs, and its relationship to Cyclocephala with a phylogenetic analysis of 2899 bp of DNA sequence data and 18 morphological characters. All five species of Mimeoma were included in analyses along with species of Cyclocephala D ejean, Dyscinetus H arold and Tomarus E richson as outgroup taxa. Nearly complete 28S , 12S and CO1 data were collected from 26 of 29 specimens, of which 16 samples were pinned, museum specimens. 28S data strongly support a nonmonophyletic Mimeoma ; mitochondrial data ( CO1 and 12S ) suggest that Mimeoma species are nested within an apical clade of other Cyclocephala species; combined molecular and morphological data identify two strongly supported clades of Mimeoma species but do not support their sister relationship. Combined data show that Mimeoma species are nested within Cyclocephala , thus rendering Cyclocephala paraphyletic. Mimeoma is synonymized within Cyclocephala resulting in the following new combinations: Cyclocephala acuta A rrow n.comb ., Cyclocephala englemani ( R atcliffe) n.comb ., Cyclocephala maculata B urmeister n.comb ., Cyclocephala nigra ( E ndrödi) n.comb . and Cyclocephala signatoides H öhne n.comb . Our results demonstrate that pinned, museum specimens can be used to obtain DNA sequence data (particularly high‐copy gene regions) for evolutionary studies, and provide the first empirical support that host‐plant associations within cyclocephaline scarab clades are conserved at the plant family‐level.

In the context of climate change’s detrimental effects on agricultural production and food security, climate-smart agriculture (CSA) strategies constitute a promising approach to reduce vulnerability and boost adaptation capacity and resilience within farmers. However, CSA strategies should address gender dynamics to reach their full potential. This study analyzed the barriers and opportunities for the implementation of gender-sensitive CSA strategies in rural Guatemala, a low-latitude country with a high gender gap index, through the perceptions of agricultural extensionists. For this purpose, we conducted an online survey among Guatemalan agricultural extensionists who attended a series of Climate Services for Agriculture workshops between May and July 2021 and analyzed the results using a qualitative approach. Results suggest that women in rural Guatemala are frequently excluded from climate information access, agricultural training, and decision-making spaces in which agricultural resource management strategies are defined. We argue that this exclusion represents a barrier to the improvement in adaptation capacity and resilience and that gender inequity should be addressed to implement successful gender-sensitive CSA approaches. Generating gender-sensitive indicators and training extensionists against gender bias could be a starting point, but further research is necessary to understand gender dynamics in rural Guatemala.