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The longhorn beetle tribe Dorcasomini exhibits remarkable endemism and species richness in Madagascar. Among the diurnal genera of Dorcasomini, Tsivoka Villiers, 1982 (Coleoptera: Cerambycidae) is distinguished by its coloration and elytral patterning. In this study, we present a taxonomic review focusing on Tsivoka, identifying a total of four species, including one species new to science: T. humeralis sp. nov.; T. peyrierasi Villiers, 1982; T. simplicicollis (Gahan, 1890); and T. testaceipes (Fairmaire, 1889). Descriptions, photographs, and a taxonomic key are provided for species identification. Additionally, we provide a distribution map for each species based on specimen information.  

Neoclytus acuminatus acuminatus, the red-headed ash borer, is a wood-boring longhorn beetle (Cerambycidae: Cerambycinae) native to North America and introduced in Eurasia and South America. Its larvae develop in dying or recently dead hardwood trees, including ecologically and economically significant species of ash, hickory, and oak. We sequenced, assembled, and annotated the genome of a female N. acuminatus and compared it to the publicly available genomes of other cerambycid species. The 508 Mb N. acuminatus genome assembly spanned 20 contigs (19 nuclear + 1 mitochondrial), with an N50 of 52.59 Mb and largest contig of 61.20 Mb. A moderately high fraction of the genome (62.63%) comprised repetitive sequences, with nearly all (99.4%) expected single-copy orthologous genes (BUSCOs) present and fully assembled. We identified 2 contigs as fragments of the N. acuminatus sex chromosome. Genome annotation identified 12,899 genes, including 109 putative horizontally transferred loci. Synteny analysis identified well-conserved blocks of collinearity between the N. acuminatus genome and other Cerambycidae. The genome contains a similar number of genes encoding putative plant cell wall degrading enzymes as other Cerambycidae. The N. acuminatus genome provides new insights into genome evolution in the family Cerambycidae, known for its rich diversity of xylophagous species, and provides a new viewpoint from which to study the evolution and genomic basis of traits such as wood-feeding and olfaction in beetles and other insects. 

Abstract Fungus weevils (family Anthribidae) are morphologically and ecologically diverse, with highly varied feeding habits, mainly mycetophagy but also phytophagy, palynophagy and entomophagy. The phylogeny of the family is virtually unexplored, its evolutionary history obscure; thus, the existing classification is controversial and likely artificial. We generated the first multi‐gene higher‐level phylogeny estimate of Anthribidae using DNA data from 400 nuclear genes obtained via anchored hybrid enrichment from 40 species representing 17 tribes plus generaincertae sedis. As in previous studies, the family Anthribidae was consistently recovered as the sister group of Nemonychidae. We recovered two main clades in Anthribidae as sister groups with strong statistical support, viz. a monophyletic subfamily Urodontinae and the traditionally recognized Anthribinae, which was rendered paraphyletic by the subfamily Choraginae. Paraphyly and polyphyly among tribes of Anthribinae indicate that current tribal concepts—all based on morphology and without phylogenetic analysis—are artificial. Based on our results, we subsume the subfamily Choraginae into Anthribinae and place its six current tribes (Apolectini, Araecerini, Choragini, Cisanthribini, Valenfriesiini and Xenorchestini) in an expanded subfamily Anthribinae. We also transfer three genera currently treated as Anthribinaeincertae sedisto three generally recognized tribes, namelyPleosporiusHolloway to Sintorini,XylanthribusKuschel to Proscoporhinini andAnthribidusFåhraeus to Platystomini. The phylogenetic positions of Urodontinae and Trigonorhinini suggest that phytophagy is the ancestral feeding mode of Anthribidae, with a few taxa of Anthribinae having secondarily evolved plant‐feeding from mycetophagy, the predominant feeding habit of the subfamily. Overall, our results provide the first molecular phylogenetic context for research on Anthribidae and a first step towards reconstructing a natural tribal classification of the Anthribinae. Our study highlights the need for a phylogenetic approach, sampling of type genera and deeper taxon sampling to identify natural tribal‐level groupings. 

The rise of angiosperms to ecological dominance and the breakup of Gondwana during the Mesozoic marked major transitions in the evolutionary history of insect-plant interactions. To elucidate how contemporary trophic interactions were influenced by host plant shifts and palaeogeographical events, we integrated molecular data with information from the fossil record to construct a time tree for ancient phytophagous weevils of the beetle family Belidae. Our analyses indicate that crown-group Belidae originated approximately 138 Ma ago in Gondwana, associated with Pinopsida (conifer) host plants, with larvae likely developing in dead/decaying branches. Belids tracked their host plants as major plate movements occurred during Gondwana’s breakup, surviving on distant, disjunct landmasses. Some belids shifted to Angiospermae and Cycadopsida when and where conifers declined, evolving new trophic interactions, including brood-pollination mutualisms with cycads and associations with achlorophyllous parasitic angiosperms. Extant radiations of belids in the generaRhinotia(Australian region) andProterhinus(Hawaiian Islands) have relatively recent origins. 

Abstract Insect antennae are crucial sensory organs that house numerous sensilla with receptors for perceiving a wide variety of cues dominating their world. Historically, inconsistent terminology and criteria have been used to classify antennal sensilla, which has greatly impeded the comparison of data even across closely related species. Longhorn beetles (Coleoptera: Cerambycidae) are no exception to this quandary, and despite their prominent antennae, few studies have investigated their antennal morphology and ultrastructure, and none have compared sensillar diversity and variation among cerambycids. Existing studies of longhorn beetle antennal sensilla include only 29 species in five of the eight cerambycid subfamilies and include misidentified sensilla types and conflicting terminology. As such, it is very difficult to conduct comparative morphological studies of antennal sensilla in longhorn beetles and challenging to understand inter- and intra-specific variation in the sensory systems of these beetles. To facilitate future comparative studies, we reviewed all accessible published papers that have used scanning and transmission electron microscopy (SEM and TEM) to investigate antennal sensilla in cerambycids, and present a first attempt at standardizing the classification of their documented sensilla types and subtypes. Specifically, we discuss seven major types of antennal sensilla (Böhm bristles, sensilla chaetica, chemosensory hairs, sensilla basiconica, dome shaped organs, sensilla coeloconica, and sensilla auricillica). We also imaged the antennae of relevant species of longhorn beetles using SEM and included images exemplifying as many of the sensilla types and subtypes as possible. 

Abstract Acoustic communication is enabled by the evolution of specialised hearing and sound producing organs. In this study, we performed a large-scale macroevolutionary study to understand how both hearing and sound production evolved and affected diversification in the insect order Orthoptera, which includes many familiar singing insects, such as crickets, katydids, and grasshoppers. Using phylogenomic data, we firmly establish phylogenetic relationships among the major lineages and divergence time estimates within Orthoptera, as well as the lineage-specific and dynamic patterns of evolution for hearing and sound producing organs. In the suborder Ensifera, we infer that forewing-based stridulation and tibial tympanal ears co-evolved, but in the suborder Caelifera, abdominal tympanal ears first evolved in a non-sexual context, and later co-opted for sexual signalling when sound producing organs evolved. However, we find little evidence that the evolution of hearing and sound producing organs increased diversification rates in those lineages with known acoustic communication. 

Abstract Phylogenomics via ultraconserved elements (UCEs) has led to improved phylogenetic reconstructions across the tree of life. However, inadvertently incorporating non‐targeted DNA into the UCE marker design will lead to misinformation being incorporated into subsequent analyses. To date, the effectiveness of basic metagenomic filtering strategies has not been assessed in arthropods. Designing markers from museum specimens requires careful consideration of methods due to the high levels of microbial contamination typically found in such specimens. We investigate if contaminant sequences are carried forward into a UCE marker set we developed from insect museum specimens using a standard bioinformatics pipeline. We find that the methods currently employed by most researchers do not exclude contamination from the final set of targets. Lastly, we highlight several paths forward for reducing contamination in UCE marker design.