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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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This content will become publicly available on January 1, 2026
A taxogenomic view of the genus Torulaspora: an expansion from ten to twenty-two species
The yeast genusTorulaspora(subphylumSaccharomycotina, familySaccharomycetaceae) is mostly known from its type species,T. delbrueckii, a frequent colonizer of wine and sourdough bread fermentations. The genus currently contains 10 species that are typically found in various natural terrestrial environments in temperate and tropical climates. Here we employ taxogenomic analyses to investigate a large collection ofTorulasporastrains obtained in multiple surveys we carried out in Asia, Australasia, North America, South America, and Europe, and to which we added several strains maintained in culture collections. Our analyses detected twelve novel species that are formally described here, thereby more than doubling the species diversity ofTorulaspora. We also sketch a genotype-phenotype map for the genus and show how the complex relationship between key genes and the physiological traits they control both between and within species. This remarkable increase in the number of species in the genusTorulasporahighlights how limited the current inventory of fungal taxa is. It also shows how integrated taxogenomic approaches can foster the assessment of species circumscriptions in fungi.
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- Award ID(s):
- 2110403
- PAR ID:
- 10609459
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Persoonia - Molecular Phylogeny and Evolution of Fungi
- Date Published:
- Journal Name:
- Persoonia - Molecular Phylogeny and Evolution of Fungi
- ISSN:
- 0031-5850
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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