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A multigene phylogenetic assessment of North American species of Mallocybe is presented based on analyses of rpb1, rpb2, ITS, and 28S rDNA nucleotide data. This framework enables a systematic revision of the genus for 16 eastern North American species and captures taxonomic and phylogenetic diversity in a global context. A grade of two unusual and poorly known North American species stems from the most recent common ancestor of the genus that gives rise to three core subgroups named here as clades Unicolores, Nothosperma, and Mallocybe. The grade of taxa includes the poorly known Lepista praevillosa from Florida and a new species from the southern Appalachians, M. montana, both of which appear to be narrow-range endemics. Clade Nothosperma is characterized by Australian and New Zealand species, whereas clade Unicolores is composed of six species from eastern North America and East Asia. Clade Mallocybe is dominated by numerous north temperate taxa and constitutes the sister group to clade Nothosperma. These major clades are distinguished by a combination of phylogeny, morphology, geographic distribution, and ecology. In addition, four North American species are described as new: M. leucothrix, M. luteobasis, M. montana, and M. tomentella. Several names originating in North America, long ignored or misunderstood in the literature, are revitalized and established by type comparisons and modern reference material collected from or near type localities. In addition, 11 species were subjected to mass spectrometry muscarine assays, none of which contained detectable amounts of muscarine except for two: M. sabulosa and M. praevillosa. This confirms a diffuse phylogenetic distribution of muscarine within the genus. Taxonomic descriptions are presented for 16 species, several synonymies proposed, and four new combinations made. A key to species of eastern North American Mallocybe is presented, along with illustrations of important diagnostic features.
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Species Delimitation of Eastern Pinesnake Complex (Pituophis melanoleucus)
The eastern Pinesnake (Pituophis melanoleucus) is found throughout eastern United States. Taxonomy in this group has been controversial with several conflicting species designations. Three subspecies of the eastern Pinesnake have prevailed in the literature to their geographic locations and scale coloration: the northern Pinesnake (P. m. melanoleucus), the Florida Pinesnake (P. m. mugitus), and the Black Pinesnake (P. m. lodingi). Within the region, there are several major barriers to dispersal, particularly major river drainage systems and human modification of the longleaf pine habitat. Consistently, a lack of phylogenetic resolution has plagued these taxa in prior studies. The goal of this study was to examine the taxonomic validity of the eastern Pinesnake complex using single nucleotide polymorphisms (SNPs) isolated from ultra-conserved elements (UCEs) in phylogenetic and population genetic approaches. Molecular species delimitation approaches indicated that the population of eastern Pinesnake exhibits population structure across its range that may rise to the level of being new species.
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- Award ID(s):
- 2113425
- PAR ID:
- 10525733
- Editor(s):
- Carstens, Bryan
- Publisher / Repository:
- Bulletin of the Society of Systematic Biologists
- Date Published:
- Journal Name:
- Bulletin of the Society of Systematic Biologists
- Volume:
- 2
- Issue:
- 1
- ISSN:
- 2768-0819
- Page Range / eLocation ID:
- 1 to 14
- 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/10.18061/bssb.v2i1.9423
