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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.
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This content will become publicly available on August 30, 2025
What does the history of Theraphosidae systematics tell us about the future of tarantula taxonomy?
Systematics provides the foundational knowledge about the units of biodiversity, i.e., species, and how we classify them. The results of this discipline extend across Biology and can have important impacts on conservation. Here we review the systematic and taxonomic practices within Theraphosidae over the last 260 years. We examine the rate of newly described species and investigate the contemporary practices being used in the description of new genera and species. There have been two large waves of theraphosid taxonomy, with an explosive growth of newly described species and author combinations in the last 60 years. We look back and find that during 2010–2024 contemporary practices in theraphosid systematics and taxonomy have remained largely static, being dominated by morphology-based approaches. Over this period, only 10% of newly described species incorporated DNA data or explicitly stated the species concept used. Similarly for genera, only five of the 37 newly described genera over that time were supported as distinct and monophyletic by DNA. We highlight the taxonomic movement of species among Theraphosidae, Barychelidae, and Paratropididae; however, given the limited molecular sampling for the two latter families, the boundaries of these families remain a significant area of needed research. To promote inclusivity, we provide a copy of this paper in Spanish as supplementary material.
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- Award ID(s):
- 2144339
- PAR ID:
- 10555697
- Publisher / Repository:
- Frontiers in Arachnid Science
- Date Published:
- Journal Name:
- Frontiers in Arachnid Science
- Volume:
- 3
- ISSN:
- 2813-5083
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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