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Abstract The terrestrial isopod genusLigidiumincludes 58 species from Europe, Asia, and North America. In Eastern North America four species are recognized:L. floridanumandL. mucronatum, known just from their type localities in Florida and Louisiana respectively,L. blueridgensis, endemic to the southern Appalachians, andL. elrodii, widespread from Georgia to Ontario. The genus shows a marked morphological conservatism, and species are differentiated mostly by small morphological differences; it is not always easy to determine if such variability represents inter‐ or intraspecific variation. Here, we explore the diversity ofLigidiumfrom the southern Appalachian Mountains, exploring the congruence of morphologically defined groups with multilocus phylogenetic reconstructions and molecular species delimitation methods. We have studied a total of 130 specimens from 37 localities, mostly from the southern Appalachians, and analysed mtDNA (Cox1) and nuclear (28S, NaK) sequences. Morphologically, we recognized eight morphotypes, most of them assignable to current concepts ofL.elrodiiandL.blueridgensis. Phylogenetic analyses supported the evolutionary independence of all morphotypes, and suggest the existence of 8–9 species, including limited cryptic diversity. Single‐locus delimitation analyses based on mtDNA data suggest the existence of a much higher number of species than the multilocus analyses. The estimated age of the ancestors of sampled lineages indicates a long presence of the genus in eastern North America and old speciation events through the Miocene. Our results indicate a higher diversity than previously thought among theLigidiumpopulations present in the southern Appalachian Mountains, with several species to be described.
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Four new species of Albomagister (Agaricales) from eastern North America
Four new species of Albomagister, a genus of Tricholomataceae in the order Agaricales, are described and illustrated from eastern North America. All four are relatively rare or geographically restricted but two have a broad geographical distribution occurring in southeast Canada and in the southern Appalachians. This study increases the number of known species in the genus from three to seven, five of which occur in eastern North America. A broad concept for the genus is discussed. Illustrations and descriptions of the North American taxa are presented, along with a taxonomic key to the known seven species in the genus worldwide.
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- Award ID(s):
- 2030779
- PAR ID:
- 10624928
- Publisher / Repository:
- Canadian Science Publishing
- Date Published:
- Journal Name:
- Botany
- Volume:
- 102
- Issue:
- 9
- ISSN:
- 1916-2790
- Page Range / eLocation ID:
- 355 to 365
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1139/cjb-2024-0058
