Figure 1. Pseudocyphellaria rainierensis in the Colonel Bob Wilderness near Quinault, WA. Photograph courtesy of S. Sharrett.

Pseudocyphellaria rainierensis (Imshaug), commonly known as the old-growth specklebelly, is a epiphytic tripartite lichen (Figure 1). The species was first described in 1948 by Henry Imshaug from specimens collected along the Ohanapecosh River within the boundaries of Mount Rainier National Park in Washington state (Imshaug, 1950). P. rainierensis is characterized by a blue-green to blue-gray upper surface, a white to tan lower surface speckled with white pores called pseudocyphellae, and the presence of sparse to abundant lobules and isidia (Imshaug, 1950; McCune & Geiser, 1999). The species has rarely been observed producing apothecia (Sillet et al, 2000). P. rainierensis plays an important role in in forest nitrogen and water cycles and food webs as a food source for invertebrates (Glavich, 2013).

P. rainierensis is endemic to western North America from southeastern Alaska to central Oregon (Glavich ,2013). The species is found in the mid to lower canopy of humid, old-growth mixed-conifer forests at elevations ranging from sea level to 1220 m (4000 ft) (Glavich, 2013). P. rainierensis has been observed growing over epiphytic bryophytes and on the bark of the following tree and shrub species: Pacific silver fir (Abies amabilis), Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), subalpine fir (Abies lasiocarpa), Pacific yew (Taxus brevifolia), Sitka spruce (Picea sitchensis), western redcedar (Thuja plicata), bigleaf maple (Acer macrophyllum), vine maple (Acer circinatum), red alder (Alnus rubra), cascara (Rhamnus purshiana), chinquapin (Chrysolepis chrysophylla), black cottonwood (Populus trichocarpa), and Pacific rhododendron (Rhododendron macrophyllum) (Glavich, 2013). The species is sporadically distributed throughout its range, and is often absent from viable habitats (Glavich 2013; Sillet et al 2000).

Figure 2. Diagram illustrating the range of Pseudocyphellaria rainierensis. Diagram designed by S. Sharrett.

P. rainierensis is considered vulnerable (S3) in Oregon, apparently secure (S4) in Washington, and imperiled (S2) in Alaska and British Columbia, Canada (Figure 3) (NatureServe 2022). The species has been given special concern status in Canada under the Species at Risk Act (SARA) and by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) (NatureServe, 2022). P. rainierensis is currently under assessment by the International Union of the Conservation of Nature (IUCN) to determine its global status as part of the IUCN Red List of Threatened Species (Allen et al 2021).

Figure 3. Map illustrating the conservation status of Pseudocyphellaria rainierensis by state/province. Map courtesy of NatureServe.org

Populations of Pseudocyphellaria rainierensis have experienced a >30% decline in the last 90 years due to timber extraction and climate-driven wildfires (Allen et al 2021; Glavich 2013). The Beachie Creek Fire, which burned 193,572 acres in the Willamette National Forest in fall 2020, destroyed one of the largest known populations of P. rainierensis in Oregon (Allen et al 2021). Populations in Washington’s Gifford Pinchot National Forest may have been similarly impacted by the 24,995 acre Big Hollow Fire which burned from September through October 2020 (Allen et al 2021).

Research

Research Objectives

The primary objectives of our research are

  1. to delimit the current distribution of Pseudocyphellaria rainierensis,
  2. to determine the role of land use/land cover in the distribution of the species, and
  3. to characterize the population genetic structure of the species across its range.