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Abstract Myrsidea Waterston, 1915 (Phthiraptera: Menoponidae) is the most diverse genus of avian chewing lice. Myrsidea has a global distribution, is thought to be highly host-specific, and parasitizes mostly passerine birds. However, the rate of taxonomic studies describing new species is relatively low, and it is thought that much of the diversity of Myrsidea is yet to be discovered. This low rate of taxonomic description for this genus, and many others, may be related to the time-consuming nature of morphological species description and a lack of expertise in louse taxonomy. Furthermore, most of the taxonomic revisions and reviews have focused on specific host families, and no comprehensive review of the morphology and molecular work of Myrsidea has been completed in the last 20 years. Here, we review the taxonomy and systematics of Myrsidea to (i) describe this chewing louse genus and its biological importance; (ii) describe current problems with its taxonomy; (iii) simplify and summarize morphological descriptions; (iv) summarize molecular data; and (v) provide a comprehensive checklist of the Myrsidea species, with all publications and localities of occurrence included. Together, we hope that this information will provide researchers with a single source of information on the genus Myrsidea, making it easier for work to proceed on its taxonomy, systematics, ecology, and evolution. Importantly, our work highlights important gaps in our knowledge of Myrsidea, providing guideposts on where future work on Myrsidea is needed. 

Abstract Classification of the biological diversity on Earth is foundational to all areas of research within the natural sciences. Reliable biological nomenclatural and taxonomic systems facilitate efficient access to information about organisms and their names over time. However, broadly sharing, accessing, delivering, and updating these resources remains a persistent problem. This barrier has been acknowledged by the biodiversity data sharing community, yet concrete efforts to standardize and continually update taxonomic names in a sustainable way remain limited. High diversity groups such as arthropods are especially challenging as available specimen data per number of species is substantially lower than vertebrate or plant groups. The Terrestrial Parasite Tracker Thematic Collections Network project developed a workflow for gathering expert-verified taxonomic names across all available sources, aligning those sources, and publishing a single resource that provides a model for future endeavors to standardize digital specimen identification data. The process involved gathering expert-verified nomenclature lists representing the full taxonomic scope of terrestrial arthropod parasites, documenting issues experienced, and finding potential solutions for reconciliation of taxonomic resources against large data publishers. Although discordance between our expert resources and the Global Biodiversity Information Facility are relatively low, the impact across all taxa affects thousands of names that correspond to hundreds of thousands of specimen records. Here, we demonstrate a mechanism for the delivery and continued maintenance of these taxonomic resources, while highlighting the current state of taxon name curation for biodiversity data sharing. 

Nucleotide base composition plays an influential role in the molecular mechanisms involved in gene function, phenotype, and amino acid composition. GC content (proportion of guanine and cytosine in DNA sequences) shows a high level of variation within and among species. Many studies measure GC content in a small number of genes, which may not be representative of genome-wide GC variation. One challenge when assembling extensive genomic data sets for these studies is the significant amount of resources (monetary and computational) associated with data processing, and many bioinformatic tools have not been optimized for resource efficiency. Using a high-performance computing (HPC) cluster, we manipulated resources provided to the targeted gene assembly program, automated target restricted assembly method (aTRAM), to determine an optimum way to run the program to maximize resource use. Using our optimum assembly approach, we assembled and measured GC content of all of the protein-coding genes of a diverse group of parasitic feather lice. Of the 499 426 genes assembled across 57 species, feather lice were GC-poor (mean GC = 42.96%) with a significant amount of variation within and between species (GC range = 19.57%-73.33%). We found a significant correlation between GC content and standard deviation per taxon for overall GC and GC₃, which could indicate selection for G and C nucleotides in some species. Phylogenetic signal of GC content was detected in both GC and GC₃. This research provides a large-scale investigation of GC content in parasitic lice laying the foundation for understanding the basis of variation in base composition across species.