Coloration is an important phenotypic trait for taxonomic studies and has been widely used for identifying insect species and populations. However, coloration can be a poor diagnostic character for insect species that exhibit high polymorphism in this trait, which can lead to over-splitting of taxonomic units. In orchid bees, color variation has been interpreted by different taxonomists as either polymorphism associated with Müllerian mimicry complexes or diagnostic traits for species identification. Despite this uncertainty, integrative approaches that incorporate multiple independent datasets to test the validity of hair coloration as a character that identifies independent evolutionary units have not been used. Here, we use phylogenomic data from Ultraconserved Elements (UCEs) to explore whether color phenotypes in the widespread orchid bee species complexes Eulaema meriana and Eulaema bombiformis (Hymenoptera: Apidae: Euglossini) correspond to independent lineages or polymorphic trait variation within species. We find that lineages within both species are structured according to geography and that color morphs are generally unassociated with evolutionarily independent groups except for populations located in the Atlantic Forest of Brazil. We conclude that there is compelling evidence that E. atleticana and E. niveofasciata are subspecies of E. meriana and E. bombiformis, respectively, and not different species as previously suggested. Therefore, we recognize Eulaema meriana atleticana comb. n. and Eulaema bombiformis niveofasciata comb. n. and discuss their morphological characteristics. We make recommendations on the use of color traits for orchid bee taxonomy and discuss the significance of subspecies as evolutionary units relevant for conservation efforts.

For over a century, the metapleural gland, an exocrine gland above the hind coxa, has been thought to be a unique structure for ants (Hymenoptera: Formicidae), and regarded as a catalyst for the ecological and evolutionary success of the family. This gland is one of the most researched exocrine glands in arthropods and its anatomy, ultrastructure, and chemistry are well documented. Herein, we describe an exocrine gland from the proctotrupoid wasp Pelecinus polyturator (Hymenoptera: Pelecinidae) with a similar position, structure, and chemistry to the ant metapleural gland: it is located just above the hind coxa, corresponds to an externally concave and fenestrated atrium, is composed of class 3 gland cells, and its extract contains relatively strong acids. We discover that the pelecinid gland is associated with the dilator muscle of the first abdominal spiracle, a trait that is shared with ants, but remained overlooked, possibly due to its small diameter, or obfuscation by the extensive metapleural gland. We also provide a biomechanical argument for passive emptying of the gland in both taxa. Pelecinids and ants with metapleural glands share a close association with soil. The pelecinid metapleural gland might therefore also have an antiseptic function as suggested for ants. We examined 44 other Hymenoptera families and found no glands associated with the oclusor apodeme or any signs of external modification. Our results strongly indicate that this complex trait (anatomical & chemical) evolved independently in ants and pelecinid wasps providing an exceptional system to better understand exocrine gland evolution in Hymenoptera.

We present the first dated molecular phylogeny of the Cerurinae moths (Notodontidae), based on sequence data for 666 loci generated by anchored hybrid enrichment. Monophyly of Cerurinae is corroborated, which includes the following genera: Pararethona Janse, Pseudorethona Janse, Oreocerura Kiriakoff, stat. rev., Cerurella Kiriakoff, Notocerura Kiriakoff, Hampsonita Kiriakoff, Afrocerura Kiriakoff, Cerurina Kiriakoff, Neoharpyia Daniel, Furcula Lamarck, Neocerura Matsumura, Americerura St Laurent and Goldstein, gen. nov., Cerura Schrank, and Kamalia Koçak & Kemal. The type species of the Neotropical genus Tecmessa Burmeister, T. annulipes (Berg), which had been incorrectly assigned to Cerurinae, is recovered in Heterocampinae; and Americerura gen. nov. is proposed to receive 17 unambiguously cerurine species transferred from Tecmessa. Divergence time estimates recover a crown age of Notodontidae roughly coincident with the K-Pg boundary, and a late-Oligocene crown age for Cerurinae. An African origin is inferred for Cerurinae, followed by colonization of the Palearctic, the Americas, Indomalaya, and Australasia during the Miocene. At least three independent colonizations of the Americas are inferred, one in the mid-Miocene associated with ancestral Americerura gen. nov. and two in the Pliocene and Pleistocene within Furcula. We hypothesize that the global spread of Cerurinae was enabled by that of its primary caterpillar foodplants in the Salicaceae. State-dependent diversification analyses suggest that cerurines diversified most rapidly in temperate climates.