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Abstract Bumble bees (Bombus) exhibit exceptional diversity in setal body color patterns, largely as a result of convergence onto multiple Mullerian mimicry patterns globally. When multiple species cross the same sets of mimicry complexes, they can acquire the same color polymorphisms, providing replicates of phenotypic evolution. This study examines the genetic basis of parallel color pattern acquisition in three bumble bee taxon pairs in western North America that shift between orange-red and black mid-abdominal segmental coloration in Rocky Mountain and Pacific Coastal mimicry regions: polymorphic Bombus vancouverensis and B. melanopygus, and sister species B. huntii and B. vosnesenskii. Initial gene targets are identified using a genome-wide association study, while cross-developmental transcriptomics reveals genetic pathways leading to final pigmentation genes. The data show all three lineages independently target the regulatory region of a segmental-fate determining Hox gene, Abdominal B (Abd-B), for this color transition. For B. vancouverensis and B. melanopygus, this involves different deletions in the same location, and all mimicry pairs differentially express Abd-B and ncRNAs in this locus. Transcriptomics reveals a shared core gene network across species, where Abd-B interacts with nubbin and pigment enzyme ebony to decrease black melanin production in favor of paler, redder morphs. Expression of multiple genes in the melanin biosynthesis pathway is modified to promote this phenotype, with differing roles by taxon. Replicated morphologies unveil key genes and a Hox gene hotspot, while enabling evolutionary tracking of genetic changes to phenotypic changes and informing how gene regulatory networks evolve. 

We describe new species in the genus Ceroptres Hartig, 1840 (Hymenoptera: Cynipidae: Ceroptresini) represented by voucher material sequenced by Ward et al. (2024). We describe 22 new species, all authored by Nastasi, Smith, & Davis: C. anansii sp. nov., C. anzui sp. nov., C. bruti sp. nov., C. curupira sp. nov., C. daleki sp. nov., C. dandoi sp. nov., C. demerzelae sp. nov., C. iktomii sp. nov., C. jabbai sp. nov., C. jarethi sp. nov., C. lokii sp. nov., C. lupini sp. nov., C. mallowi sp. nov., C. promethei sp. nov., C. sandiegoae sp. nov., C. selinae sp. nov., C. soloi sp. nov., C. songae sp. nov., C. swiperi sp. nov., C. thrymi sp. nov., C. tikoloshei sp. nov., and C. zorroi sp. nov. After our taxonomic treatment, the genus Ceroptres includes 43 species, all but three of which are known from North America. Among our new species are two reared from cecidomyiid midge galls, an association previously recorded but without valid taxonomic association. We provide new records for two additional previously described species; we record C. ensiger (Walsh, 1864) from Pennsylvania and confirm characters for the male, and we record C. lanigerae Ashmead, 1885 from Texas. We also examined several putative species corresponding to either C. cornigera Melika & Buss, 2002 and/or C. frondosae Ashmead, 1896, which we regard as a species complex that requires elucidation in future studies. To enable further studies on Ceroptres, we provide an updated key to North American females. Overall, we find that species of Ceroptres are host specialists associated with a single host gall species or several galls that are phylogenetically or ecologically related. We suggest that there are many North American species of Ceroptres, possibly hundreds, still awaiting collection and characterization.  

Endophytic insects, including gall insects and leaf miners, are prominent in both natural and agricultural plant communities. We catalog the endophytic insect fauna in North America that are known to associate with rosinweeds (SilphiumL., Heliantheae, Asteraceae). We provide details on host plant species, brief descriptions of insect associations, and known distributions of their association withSilphiumspecies. We report associations with rosinweeds for 41 insect species from 18 families across four insect orders and detail the host plant tissue where these insects occur. The complex community we describe suggests that a further study of rosinweed endophytic insects could be useful to understanding evolution of host‐plant preferences andSilphiumspecies boundaries. 

Cryptic species present challenges across many subdisciplines of biology. Not all “cryptic” species, however, are truly cryptic; many are simply underexplored morphologically. We examined this idea for theAntistrophus rufusspecies complex, which previously contained three species thought to be morphologically cryptic. To determine whether theA. rufuscomplex are truly cryptic species, we assessed species boundaries of members of theA. rufusspecies complex using morphological, ecological, and DNA barcode data, and tested whether a set of 50 morphological characters could adequately diagnose these species. We revealed that this complex includes five species, and that there are useful phenotypic diagnostic characters for all members of this species complex. This enabled redescription of four species and the description ofAntistrophus laurenaeNastasi,sp. nov., which induces externally inconspicuous galls in stems ofSilphium integrifoliumMichx., a host not associated with other members of the complex. We use these new diagnostic characters to construct a key to the five species of therufuscomplex. We conclude that theA. rufuscomplex was not a true case of cryptic species. Our Bayesian analysis of DNA barcode data suggests possible cospeciation of members of therufuscomplex and theirSilphiumhost plants, but further study is necessary to better understand the evolution of host use in the lineage.