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Two new species belonging to the lichen genus Anaptychia are described from western North America. Anaptychia nevadensis is superficially similar to the Eurasian A. desertorum but is distinguished by having longer ascospores, in producing scant pruina only near the lobe tips, and in regularly producing variolaric acid. Anaptychia roemerioides is described to accommodate North American material which has previously been called A. ulotrichoides. It is macro-morphologically identical to the Asian species A. roemeri but differs in having longer ascospores and conidia. Both new species are strongly supported by phylogenetic analysis of ITS sequences. We also call attention to the existence of a further undescribed but possibly cryptic species within A. elbursiana. Variolaric acid is newly reported to occur occasionally in A. desertorum and A. elbursiana. A global key to the desert species of Anaptychia is provided. [ABSTRACT FROM AUTHOR]

Twenty-five North American lichens are issued in Fascicle VIII of the "Anderson and Shushan: Lichens of Western North America" series, numbers 176–200. This fascicle is comprised of material representing specimens from the Rhizoplaca melanophthalma aggregate, including the vagrant taxa R. arbuscula, R. haydenii, and R. idahoensis; two collections representing unattached forms in the R. porteri group – R. melanophthalma ssp. crispa and an erratic form of R. porteri; and two umbilicate saxicolous taxa, R. robusta and R. shushanii, the former described as new to science here. We also provide the first morphological description for R. shushanii, a species that was initially described based on diagnostic DNA sequence characters. [ABSTRACT FROM AUTHOR]

Based on field collections made during the summers of 1987, 1988, and 1989, we report 159 species of lichens in 69 genera for the Jarbidge Wilderness Area (JWA) and adjacent Forest Service lands, located in the northern Great Basin, USA. Specimens were collected at 25 sites, distributed across the JWA along with two additional sites north of the wilderness boundary on Forest Service land. Collections were made from all available substrates, including rocks, bark, lignum, mosses, soil, and from the thalli of various saxicolous lichens. All basic growth forms were found, especially crustose and foliose species. Umbilicate species (Dermatocarpon spp., Rhizoplaca spp., and Umbilicaria spp.) were commonly found on rocks, while a limited number of fruticose species (Letharia spp. and Bryoria spp.) were found on bark and lignum substrates. A single, fruticose species was found on rocks (Pseudephebe minuscula). Saxicolous substrates supported the richest lichen communities, followed by corticolous and lignicolous substrates. Specifically, cottonwood spp., various conifer species, and curled leaf mountain mahogany were important bark and lignum substrates. Other taxa occurred on soil/bryophyte/detritus substrates with one species commonly collected on the thalli of various saxicolous lichens (i.e., Caloplaca epithallina). The JWA lichen flora is richer than other Nevada wilderness areas so far surveyed, with 33 putative new species records for the state of Nevada. Species richness and abundance in the JWA is likely due in part to the more mesic conditions found in the wilderness as well as its proximity to the more abundant and diverse lichen communities found in the Northern Rocky Mountains and the Pacific Northwest. Samples of two sensitive indicator species (Rhizoplaca melanophthalma and Letharia lupina) were analyzed to determine thallus concentrations of three potential air pollutants (sulfur, copper, and lead). All pollutant element concentrations were within background levels except for percent sulfur in two samples of Letharia lupina from Hummingbird Ridge (0.226%) and Emerald Lake (0.215%). Both sites are upper elevation (> 2700 m ASL) suggesting possible accumulation due to long-range transport of sulfur species from large urban areas in the Pacific Northwest. [ABSTRACT FROM AUTHOR]

Two new species belonging to the common and widespread lichen genus Physcia are described from western North America. One of these, P. occidentalis, is an obligately saxicolous species that reproduces by fragmentation, primarily through the production of largely terminal blastidia. Only a single very immature apothecium was observed among all collections. The species occurs from British Columbia to California, with outliers in Colorado. The other species, P. rhizinata, is a corticolous, typically fertile species lacking asexual propagules, and has often been confused with P. stellaris. It is presently known only from California. The close evolutionary relationship of these morphologically dissimilar taxa highlights the currently limited understanding of factors that lead to phenotypic divergence in lichen symbioses. [ABSTRACT FROM AUTHOR]

The La Sal Mountains in eastern Utah, USA, contain the only alpine habitat on the Colorado Plateau in Utah. These unique sky island alpine communities are vulnerable to a wide range of disturbances, including factors associated with the recent introduction of mountain goats (O. americanus). In order to monitor the potential impact of O. americanus, and other disturbances on alpine communities in the La Sals, we provide baseline estimate population densities for 'Wyoming range lichens' (Xanthoparmelia wyomingica) at two sites near Mount Laurel. Using the point-centered quarter and the quartered-neighbor methods, we estimate ca. 20 individuals/m2 at both sites. These estimates provide an important baseline for long-term monitoring of vulnerable alpine sites on the Colorado Plateau. [ABSTRACT FROM AUTHOR]

Lichen communities in many National Parks are diverse and perform essential but often poorly understood ecological roles. However, lichen diversity in many National Parks is poorly characterized. Because of this, limited interpretive resources are currently available. Here we report a preliminary checklist of the lichen species found in Great Basin National Park, White Pine County, Nevada, USA, including 230 species in 84 genera, identified predominantly from recent field surveys. While our study documents an impressive diversity of lichen species in the Park, we anticipate that a significant percentage of the lichen flora remains to be discovered. Our hope is that this preliminary checklist will provide a foundation for additional lichenological research in Great Basin National Park. [ABSTRACT FROM AUTHOR]

Twenty-five North American lichens are issued in this exsiccat series, numbers 151-175. In this fascicle, collections were made from nine states, including: Alaska (1), Arizona (3), California (2), Colorado (6), Idaho (1), Montana (4), Nevada (2), New Mexico (4), and Utah (2). Here, Thamnolia subuliformis (Ehrh.) W. L. Culb. (No. 173) is reported as a new species record for Utah. [ABSTRACT FROM AUTHOR]

Processes that shape biogeographic patterns in lichens have been of long-standing interest, especially in extreme environments. Lecideoid lichens in Antarctica have been relatively well-studied and are thought to have a high degree of endemism. However, recent collection efforts in montane regions of western North America have uncovered lecideoid lichens morphologically similar to some from Antarctic and South American Sub-Antarctic regions, including Lecidea andersonii Filson and L. polypycnidophora U.Rupr. & Türk. To explore the similarity between these putative conspecifics, we used ITS and MCM7 sequence data to infer relationships within a phylogenetic framework. The resulting phylogenetic reconstructions provided further evidence of the close relationship between specimens from western North America with geographically distant lecideoid populations in the Southern Hemisphere. We recovered two diverse, well-supported clades, provisionally called the L. andersonii complex and the 'Lecidea NA-ARG clade,' both including species-level subclades. A number of lecideoid species and species-level lineages thought to be endemic to Antarctica, the South American Sub-Antarctic region, or with bipolar distributions also occur in montane regions of western North America. In some cases, these species-level clades corresponded to distinct geographic regions, e.g., L. polypycnidophora, while other species failed to show phylogenetic structure corresponding to distinct geographic regions, e.g., L. andersonii. These findings bring into question the origin and prevalence of truly endemic Antarctic lichen-forming fungi. Additional investigations into lecideoid lichens, including the biogeographic connection between western North America with Antarctica, will likely provide novel perspectives into the connection between Antarctica and North America, potential colonization routes and the timing of dispersal events. [ABSTRACT FROM AUTHOR]

While the distribution and ranges of arctic plants were greatly affected by the advance and retreat of ice sheets, the impact of glacial and interglacial cycles on lichenized fungi remains largely unexplored. Inn this study we examine the impact of Pleistocene climatic changes on two closely related Xanthomendoza (Teloschistaceae, Ascomycota) species with distinct distribution patterns and reproductive strategies. We selected X. borealis, which occurs in polar regions of both hemispheres, and the corticolous X. montana, which is restricted to montane shrublands in western North America. We analyzed the complete nuclear ribosomal internal transcribed spacer region (ITS) to confirm the monophyly and relative ages of X. borealis and X. montana. We estimated molecular diversity and population demographics statistics, mismatch distributions, and Bayesian skyline plots for both species. Our data indicate that X. montana experienced a Late Pleistocene population expansion. We suggest that major shifts in vegetation types as a result of Pleistocene climate change had a substantial impact on distribution patterns and the demographic history of X. montana. In contrast, results from this study indicate that the demographic history of X. borealis is consistent with long-term stability, although low genetic variability in the ITS marker for X. borealis limits overall confidence in this inference. We propose that X. borealis has been able to maintain a stable population size across climatic shifts, likely through effective dispersal to suitable habitats and suggests that climatic conditions during Pleistocene glacial cycles were not inherently unfavorable or restrictive for some high altitude/latitude lichen-forming fungal species. Investigating mating systems for these two Xanthomendoza species may provide important insights about the factors affecting population demographics and reproduction in lichen-forming fungi in general. [ABSTRACT FROM AUTHOR]

Fungal selectivity (range of potential partners) for algal symbionts has been found to vary in lichen associations. Although a large number of studies have focused on the taxonomy and evolution of fungi in the speciose parmelioid clade (Parmeliaceae, Ascomycota), fungal-algal interactions in this ecologically and evolutionarily diverse group remain largely unexplored. In this study we investigated the algal symbionts of Xanthoparmelia fungi in western North America. We generated sequence data from a total of 58 rock shield lichens (Xanthoparmelia fungi + Trebouxia algae) collected across three sites in a subalpine community in southern Utah, USA. We explored the role of substrates, secondary metabolite variation, phenotype-based Xanthoparmelia species, mycobiont genetic population clusters, and sitespecific differences in structuring assemblages of algae. Our results indicate that Xanthoparmelia fungi associate with a broad range of Trebouxia lineages in a local, subalpine habitat. Most algae sampled form part of the diverse Trebouxia 'arboricola/gigantea' clade, while a small number of algae from outside of this clade were also found to associate with the Xanthoparmelia species investigated here. Our results also revealed multiple Trebouxia lineages within the T. 'arboricola/gigantea' clade that have not been previously recognized. Furthermore, accumulation curves suggested that additional algal diversity in rock shield lichen communities in the sampled subalpine habitat may be recovered with increased sampling. Overall, we found no clear association of algal clades with traditional phenotype-based Xanthoparmelia species, mycobiont genetic population clusters, distinct extrolites, or substrates. However, our data revealed significant genetic structuring of Trebouxia communities in separate subalpine meadow areas in a relatively homogeneous subalpine community. Significant site-specific differences in Trebouxia diversity in rock shield lichen communities and low selectivity suggest that photobiont flexibility may play an important role in overall successful colonization of rock shield lichens across a wide array of habitats in western North America. [ABSTRACT FROM AUTHOR]

In North America, the widespread sorediate lichen known as Hyperphyscia adgiutinata is shown to be heterogeneous. It contains two distinct species, one with primarily laminal soralia and another with marginal soralia. The latter taxon is here described as the new species H. confusa. Hyperphyscia adgiutinata and H. confusa have broadly overlapping distributions in North America, especially in the Midwest and Great Plains states. Where they are sympatric, H. confusa is generally the more common of the two. Descriptions and discussions for H. adgiutinata and the two other sorediate North American species, H. minor and H. pyrithrocardia, are also included, along with a key for separation of the four species. Hyperphyscia pyrithrocardia is reported for the first time from North America. [ABSTRACT FROM AUTHOR]