Considering taxonomic diversity, extant xyelid sawflies represent a very small subset of the past diversity of the group. A complementary approach to investigate evolutionary changes in this family is to consider ovipositor morphology, an ecologically important organ. New, well-preserved specimens from the UpperTriassic Ominé locality (Momonoki Formation, Mine Group; Carnian; Japan) and belonging to the †Madygellinae, one of the earliest Xyelidae subfamilies, are newly described and assigned to four new species, belonging to three genera (one being new).Two of the specimens expose body parts and wings, providing important information regarding ovipositor morphology. To further appreciate the evolution of this organ, we surveyed both fossil and extant Xyelidae. Extant forms display both extremes of the range of ovipositor types, namely the high aspect ratio “dagger-like” and “needle-like” types (in Xyelinae) and the low aspect ratio “short and wide” type (in Macroxyelinae). All known Triassic representatives display high aspect ratio ovipositor types. In contrast, Middle Jurassic to Lower Cretaceous sawflies show the highest diversity of ovipositor types for the family. Afterwards, the observed range declined and concentrated on the two, very distinct types known nowadays. Decline in ovipositor disparity was not contemporaneous in Xyelinae and Macroxyelinae: specialization occurred during the Jurassic-Cretaceous transition for the Xyelinae, while Macroxyelinae displayed their peak of diversity during the Lower Cretaceous, with a postponed decline. Ovipositor shape transition was probably accompanied with a larval diet change in Macroxyelinae. Ovipositor disparity therefore further contributes depicting extant Xyelidae as a subset on a once more diverse group.

Bumble bees (Hymenoptera: Apidae, Bombus Latreille, 1802) are critical pollinators—providing the necessary ecological services for food and crop production. In western North America, species-rich bumble bee communities inhabit mountain ranges. However, as climate change increases temperatures, montane populations are restricted to higher elevations, and their ability to disperse and maintain genetic diversity decreases as suitable habitat connecting populations decreases. This genetic isolation could lead to the extirpation of local pollinator populations and a loss of genetic diversity for pollinator species. We analyzed the genetic diversity of 4 broadly sympatric species of bumble bees with differing elevational niches—Bombus flavifrons, B. melanopygus, B. mixtus, and B. sylvicola—across the Rocky and Cascade Mountains of western North America to assess range-wide population genetic structure. We used microsatellite markers to assess genetic differentiation among populations (F_ST) and performed Bayesian clustering analyses to identify genetic groups within each study species. Further, we investigated if observed genetic differentiation within study species was better explained by isolation by distance (IBD) or isolation by resistance (IBR) by incorporating habitat suitability models (HSMs) into population structure analyses. Although we expected range-wide genetic differentiation for species with more narrow niche requirements, we found evidence of this differentiation for all 4 study species, with western populations experiencing significant genetic structure relative to inland populations. Additionally, IBR predicted genetic structure better than IBD for B. flavifrons and B. mixtus. Our results suggest that considering habitat connectivity across the geographic range of montane bumble bee species is important for understanding their population structures.

Superfamily Tipuloidea, commonly known as true crane flies, represents a taxonomically and ecologically diverse group within Diptera. Species in this clade are easily recognized by their characteristic long-legged appearance and are widespread across terrestrial and aquatic habitats. This review synthesizes the current state of Tipuloidea systematics, providing an overview of key contributions from the past that have shaped our present understanding. We review the paleontological evidence available for this group and summarize phylogenetic studies that have explored evolutionary relationships across different taxonomic levels. Although significant progress has occurred in documenting global crane fly diversity, opportunities remain to associate conspecific life stages, undertake revisionary taxonomy, and stabilize the classification system through expanded taxon sampling and the use of new genetic markers and mitochondrial genomes in future phylogenetic analyses. Finally, we highlight priority areas for future research to enhance our understanding of Tipuloidea evolution and classification.