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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. |
