Lepraria saliersiae E. Tripp & J. Watts, 2025

Lepraria saliersiae E. Tripp & J. Watts , sp. nov.

TYPE. USA. Colorado. Saguache County, BLM land east of Cochetopa Pass, Sheep Creek Road ( BLM 5252N), high elevation sage steppe dissected by mesic, boulder-rich ravines with Artemesia spp. , Abies lasiocarpa , Populus tremuloides, Rosa woodsii, and Pinus aristata , saxicolous on rocks in ravine, 9086 ft. elev., 38.199 28, -106.49064, 17 July 2024, E. Manzitto-Tripp & J. Watts 10,998 ( Holotype: COLO!; Isotype: KANU!). Figures 3–4 View FIGURE 3 View FIGURE 4 & 7 View FIGURE 7 .

Mycobank #. 860002

Description. Thallus crustose, leprose, placodioid, with (usually) crisped margins forming a conspicuously raised lip that ascends upward, prominently above primary plane of thallus, very rarely with only somewhat raised margins that are not conspicuously crisped and raised, the lips and margins conspicuously yellow in color, central portions of thallus irregularly pigmented, ranging from yellowish gray to whitish gray. Lobes indistinct to distinct, when distinct, raised, yellowed, and 1–2 mm wide. Granules irregular to less commonly subglobose, mostly ecorticate (ecorticate portions extremely yellow), typically with short projecting hyphae, to sometimes pseudocorticate (these portions whitish gray), 50–110 μm in diameter. Hypothallus consisting of thick, white, protruding hyphae, these ca. 80 μm long, segmented and branching, 2.5–3.5 μm thick. Hypothallus bearing scattered, reddish-brown, morphologically highly differentiated shiny, prominent rhizohyphae, 3.0–3.5 μm thick, branched. Photobiont chlorococcoid, cells 7–12 μm in diameter.

Etymology. This new lichen species is named in honor of Emily Saliers of the long-time musical duo, Indigo Girls. Together with Amy Ray, Emily has worked tirelessly to advocate for environmental rights and to end destructive, industrial practices that are catastrophic to both biodiversity and human livelihood. She has been a vocal opponent of (and has helped to fundraise against) the Dakota Access, Keystone, and Enbridge Pipelines, which devastate river water quality, violate treaty rights of Native Nations, and pose major threats to riparian ecosystems and the peoples that depend on them. Emily’s music is rooted in intellectual curiosity, understanding, awareness, compassion, and reflection. Her songs have been a powerful catalyst to inspire social change, which is intimately linked and crucial to the preservation of our native ecosystems and their resident species. Emily’s music has kept us company over many years of fieldwork (and microscopy!) spent documenting and conserving the biodiversity that surrounds us. This new species reminds us of Emily because its striking yellow thallus is bright, lively, and conveys a warmness.

Chemistry. Spot Tests. K+ yellow, C-, KC-, P+ orange to red, UV-. Thin Layer Chromatography: atranorin (major to trace or rarely absent), roccellic/angardianic (major to absent), pannaric acid 6-methyl ester (major), pannaric acid (major), unknown dibenzofuran A, and +/- pannaric acid 2-methyl ester (only 2 specimens).

Distribution. Lepraria saliersiae is known currently from 20 specimens deriving from 12 different counties, nine in Colorado (Boulder, Gunnison, Huerfano, Jefferson, Mineral, Otero, Park, Pitkin, Saguache, San Miguel) and three in New Mexico ( Hidalgo, San Juan, Sandoval).

Substrate & Habitat. The 20 collections of Lepraria saliersiae reported here were made primarily on rocks (or rarely overgrowing mosses in crevices) in sheltered habitats such as in micro-watersheds (i.e., less than 100 m wide) and rock crevices. The new species seems to have an affinity in particular for soft rocks such as sandstone. Lepraria saliersiae has been found growing in a variety of low to mid elevation habitats of the SoRo ranging from mixed-grass prairie ecosystems to high elevation sage-steppe and upper montane forests ranging between ~ 4,400 –10,500 ft. elev. We expect that continued surveys of the southern Rocky Mountain lichen biota (coupled with new herbarium studies of existing materials) will continue to expand the known range of this remarkable species.

Notes. In North America, Lepraria saliersiae ( Figure 4 View FIGURE 4 ) is a charismatic component of the leprose crust lichen community of the southern Rocky Mountains, distinctive by its placodioid thallus with crisped margins that form conspicuously raised lips that ascend clearly above primary plane of the thallus (i.e. normandinoides -type sensu Lendemer [2013]), its remarkable yellow pigmentation that accentuates various portions of the thallus but especially the margins, its irregularly shaped granules that vary from predominantly ecorticate with short projecting hyphae to occasionally pseudocorticate, its hypothallus that bears reddish-brown rhizohyphae that are long, branched, shiny, and reddish-brown in color, and its nearly consistent production of atranorin (in addition to other compounds). In the southern Rocky Mountains, Lepraria saliersiae has historically likely been to be confused for L. vouauxii (Hue) R.C. Harris , but that species lacks defined margins (i.e., has an aggregate-type thallus), has non-pigmented rhizohypae (where present), is chemically variable but most frequently lacks atranorin, oftentimes occurs on bark (both of which are the case for the type, L. Vouaux s.n. in Claudel, Claudel & Harmand, Lich. Gall. Praec. Exs. No. 300, H-9504035, isolectotype [photo!]; TLC=methyl pannaric acid complex only), and is phylogenetically more distantly related to Lepraria saliersiae ( Figure 3 View FIGURE 3 ; Laundon 1989; Lendemer 2013). Lendemer (2013) employs a broad species concept for L. vouauxii in North America to include many saxicolous specimens from western North America that we here treat as L. saliersiae . Consistent with the type specimen (cited above), the current contribution adopts a narrower concept of L. vouauxii to only include those specimens that occur primarily on bark or mosses and detritus over bark, lack atranorin, and have aggregate-type thalli. Based on current knowledge, we do not consider it yet known from Colorado and therefore exclude it from the key. The new species may also be confused L. membranacea (Dicks.) Vain. , which has been variously treated as present either only in eastern North America ( Lendemer 2013) or more widely recognized throughout much of North America (https://lichenportal.org/portal/). In concordance with Lendemer (2013), it is likely that L. membranacea is largely or wholly restricted to eastern North America and absent from arid regions of western North America; we therefore do not currently recognize the species as occurring in Colorado and exclude it from the key. Lepraria saliersiae can, however, be differentiated from L. membranacea ( J. Dickson s.n., BM, holotype [photo!]) because the latter, while placodioid, lacks crisped, raised margins (i.e. finkii -type sensu Lendemer [2013]), has unpigmented rhizohypae (where present), rarely produces atranorin, lacks metabolites in the methyl pannaric acid complex, and is phylogenetically more distantly related to Lepraria saliersiae ( Figure 3 View FIGURE 3 ; Laundon 1989; Lendemer 2013). We suspect that many specimens currently annotated as L. vouauxii or L. membranacea in arid, western North America likely belong to the new species: L. saliersiae . Lepraria diffusa (J.R. Laundon) Kukwa is another yellow, dibenzofuran-containing species reported from western North America (mostly from the Pacific Northwest and northern Rocky Mountains, but also from Colorado [e.g., E. Manzitto-Tripp, J. Watts, & S. Raynor 11818, E. Manzitto-Tripp & W. Manzitto-Tripp 10735, and J. Watts, E. Manzitto-Tripp, & S. Raynor 4214]) but it is easily differentiated from L. saliersiae by its aggregate-type thallus. Finally, the new species may be confused with Lepraria xerophila Tønsberg , but that is a strongly western maritime, terricolous species with exceptionally thick thalli that are uniformly whitish yellow (vs. bright yellow at the margins as in L. saliersiae ) and often squamulose so to appear similar to a Cladonia . Additionally, L. xerophila is distinct chemically from L. saliersiae as it lacks pannaric acid as a major metabolite and produces porphyrilic acid (and related compounds) and rangiformic acid and/or roccellic/angardianic as fatty acids rather than only roccellic/angardianic as in L. saliersiae . In instances where thalli of species of Lepraria are poorly developed and/or immature, TLC is highly recommended to help aid in their identification and to differentiate the new species from congeners.

In Colorado, other species of Leparia with placodioid thalli include L. eburnea J.R. Laundon , L. finkii (B. de Lesd.) R.C. Harris , and L. normandinoides Lendemer & R.C. Harris. Lepraria eburnea is similarly shades of yellow to green but lacks a crisped margin and produces alectorialic, barbatolic, and sometimes protocetraric acid. Lepraria finkii can sometimes bear yellowish green granules but lacks a crisped margin and produces zeorin, stictic acid aggregate, and sometimes roccellic/angardianic acids. Lepraria normandinoides cannot be confused with Lepraria saliersiae as it is bluish white to gray in color and produces roccellic/angardianic acid, and sometimes protocetraric acid.

Based on observations during recent field efforts, thallus morphology of Lepraria saliersiae appears to vary considerably with microclimatic conditions. In more sheltered situations over harder rocks and/or overgrowing cushion mosses, L. saliersiae tends to exhibit less conspicuously raised margins, smaller granules with less well-developed pseudocortices, and more uniformly greenish yellow thalli, thereby approaching the morphology of L. membranacea . In exposed microsites, L. saliersiae appears to be restricted to vertical to overhung faces of soft sandstones or the soil-rock interfaces where it develops strongly crisped margins, irregular granules with pseudocortices, and distinctly bicolored thalli with bright yellow margins and irregularly/patchily whitish gray centers, in some ways approaching the morphology of L. xerophila but never as thick, white, and squamulose as the latter. We have sequenced a range of these moprhologies and all were resolved as reciprocally monophyletic, with strong support (100% BS; Figure 3 View FIGURE 3 ).

The chemistry of Lepraria saliersiae is notable because it invariably produces a presumably undescribed dibenzofuran (unknown dibenzofuran A in TLC section) as a major metabolite.Unknown dibenzofuran A is characterized by an Rf value of ~ 15 in solvent A, its lack of charring after sulfuric acid and application of heat, and its longwave UV (greenish yellow) fluorescence before charring (UV- after charring). Unknown dibenzofuran A may be related to the dibenzofuran methyl porphyrilate, as this chemical species also does not char, but the latter compound has an Rf value of 23 and fluoresces purple under longwave UV.

Our phylogenetic analyses placed our five accessions of Lepraria saliersiae as reciprocally monophyletic with strong support (100% BS; Figure 3 View FIGURE 3 ). Lepraria saliersiae was resolved, also with strong support (93%), as sister to a clade (93% BS) containing collections of L. sipmaniana (Kümmerl. & Leuckert) Kukwa and L. cryptovouauxii Kukwa from Bolivia ( Figure 3 View FIGURE 3 ). Indeed, L. sipmaniana and L. cryptovouauxii are similarly placodioid, yellow in color, and produce dibenzofurans, like Lepraria saliersiae ( Laundon 1989; Flakus et al. 2011; Guzow-Krzemińska et al. 2019). However, Lepraria saliersiae can be readily differentiated from L. cryptovouauxii in having conspicuous, crisped lip-like margins, in producing pannaric acid 2-methyl ester, by its branching rhizohyphae, in never producing anthraquinones, and by the single nucleotide polymorphisms present in the nrITS DNA alignment. Lepraria saliersiae can be readily differentiated from L. sipmaniana in its granules with hyphal projections, its production of atranorin and pannaric acid 2-methyl ester (trace) (and spot tests, i.e., C-), and its typically smaller granules. So far as known, L. cryptovouauxii and L. sipmaniana have not yet been reported from North America.

Conservation Assessment. Based on our current knowledge and field exploration throughout the southern Rocky Mountains, Lepraria saliersiae is currently assessed as Endangered ( EN) under criterion D of the IUCN Red List ( IUCN 2024), which was invoked as a result of the total known population size of the species being less than 250 individuals. Lepraria saliersiae appears to be relatively widespread in Colorado based on the authors’ collections. In addition to new fieldwork throughout western North America, further study of herbarium materials currently ascribed to “ Lepraria vouauxii ” and “ Lepraria membranacea ” should be examined to determine whether these specimens may represent additional material of the new species, which may alter this preliminary IUCN assessment.

Additional Specimens Examined. USA. Colorado. Boulder County. City of Boulder Open Space & Mountain Parks, outcropping between S. Cherryvale Rd. and Marshall Drive, mixed-grass prairie and Cercocarpus montanus , Pinus ponderosa , Prunus virginiana , Ribes cereum , saxicolous at base of vertical outcropping of soft Laramie Sandstone, 39.962 026, -105.21188, 5650 ft. elev., 14 April 2025, J. Watts 3450 ( COLO!). Gunnison County. Gunnison National Forest, outcropping just south of McClure Pass, north-facing slope of Douglas Fir, Spruce, Fir, and Aspen, geology of coarse-grained sandstone, saxicolous, 39.126 761, -107.288151, 8864 ft. elev., 11 June 2025, E. Manzitto-Tripp & J. Watts 11649 ( COLO!). Gunnison National Forest, Raggeds Wilderness, Dark Canyon Trail along Anthracite Creek north of Prospect Point, south-facing outcropping of Rollins Sandstone of the Mesaverde Formation amongst Juniperus scopularum and Quercus gambelii , saxicolous in cracks, 38.960 708, -107.256943, 6940 ft. elev., 10 June 2025, J. Watts & E. Manzitto-Tripp 3902 ( COLO!). Huerfano County. Southern extent of San Isabel National Forest just west of CR 630, pinyon-juniper woodland with the occasional Ponderosa Pine over soft sandstone, saxicolous in cracks, 37.895 97, -105.15325, 8406 ft. elev., 24 May 2025, E. Manzitto-Tripp & J. Watts 11547 ( COLO!); J. Watts & E. Manzitto-Tripp 3749 ( COLO!). San Isabel National Forest, Spanish Peaks Wilderness, Wahatoya Creek, mature, open canopy, humid, riparian middle montane forest with a lush herbaceous layer, Abies concolor , Pseudostuga menziesii , and Populus tremuloides dominant, Picea engelmannii and Populus angustifolia occasional, geology of intermixed Cuchara sandstone outcroppings and hard intrusive igneous outwashed boulders, saxicolous, 37.401 99, -104.95368, 9058 ft. elev., 24 May 2025, E. Manzitto-Tripp & J. Watts 11572 ( COLO!); J. Watts & E. Manzitto-Tripp 3780 ( COLO!). Jefferson County. South Valley Park, inclined Pinus ponderosa savanna on Front Range cuesta, saxicolous on vertical soft Lyons sandstone near ephemeral stream, 39.558 099, -105.139437, 6,037 ft. elev., 4 January 2025, J. Watts & R. Wilkens 3095 ( COLO!). La Plata County. San Juan National Forest, Weminuche Wilderness, Vallecito Creek Trail (529) between the first bridge and the trailhead along the west banks of Vallecito Creek, a montane forest of Pseudostuga menziesii , Pinus ponderosa , and the occassional Picea engelmannii , Pinus flexilis , and Abies concolor , understory lush with Rubus spp. , Lonicera involucrata , Prunus americana , and Quercus gambelii , abundant granitic cliffs and outcroppings, saxicolous, 37.510 638, -107.53618, 8353 ft. elev., 19 June 2025, E. Manzitto-Tripp & J. Watts 11782 ( COLO!). Mineral County. Rio Grande National Forest, La Garita Wilderness, northwest facing slopes between Wheeler NM Trail and East Bellows Creek, a spruce bark-beetle damaged forest with Dasiphora fruticosa as the dominant shrub, large north-facing outcrops south of river, geology of intrusive igneous rocks, saxicolous, 37.831 773, -106.732012, 10483 ft. elev., 17 June 2025, E. Manzitto-Tripp & J. Watts 11699 ( COLO!). San Juan National Forest, vicinity of Treasure Falls, west-facing gulch of mixed montane forest of Abies concolor , Picea engelmannii , Pseudostuga menziesii , and Populus tremuloides , understory of Amelchier alnifolia , Quercus gambelii , and Cornus sericea , muscicolous over rock in crevice, 37.442 226, -106.875829, 8182 ft. elev., 18 June 2025, J. Watts & E. Manzitto-Tripp 4022 ( COLO!). Otero County. Comanche National Grassland, open wash dominated by Juniperus and sheltered outcrops, saxicolous at base of rocks, 37.652 519, -103.570902, 4,384 ft. elev., 27 March 2025, S. Raynor & J. Watts 6100 ( COLO!). Park County. Eagle Rock Ranch, rocky hillside with large and Artemesia dracunculus , Mertensia lanceolata , Ribes cereum , and Muhlenbergia montana , saxicolous and on moss under rock, 39.243 711, -105.644322, 9,000 ft. elev., 14 July 2023, T. Cook. s.n. ( COLO!). Pitkin County. White River National Forest, South Fork Fryingpan River, ~4 aerial miles southeast of Norrie Colony, lower subalpine forest of Spruce and Fir with the occasional Douglas Fir, Lycopodium annotinum in understory with abundant large granitic boulders densely covered in mosses and lichens, saxicolous, 39.279 27, -106.61148, 9328 ft. elev., 12 June 2025, E. Manzitto-Tripp & J. Watts 11681 ( COLO!); J. Watts & E. Manzitto-Tripp 3978 ( COLO!). San Miguel County. West-facing slope east of Fall Creek from Fall Creek Recreation Site, montane forest with Pseudotsuga menziesii and Picea englemannii and steep canyon wall of crumbling Dolores Formation sandstone, saxicolous in rock crevice, 37.978 955, -108.0298, 7,697 ft. elev., 24 July 2024, J. Watts & S. Raynor 2299 ( COLO!). New Mexico. Hidalgo County. Granite Pass, saxicolous in crack in boulder, 26 April 1992, 5,000 ft., R. Worthington 20667 ( COLO!). San Juan County. S side of Chaco Wash across from Casa Chiquita ruins, on soil and among mosses, 6,200 ft., 7 August 1979, L. Sigal & T. Nash III 16,303 ( COLO!). Sandoval Country. Bandelier National Monument, travel from Saint Peters Dome to breaks of Capulin Canyon, steep, moist, north-facing slopes with Pseudotsuga menziesii , Pinus ponderosa , and Pinus strobiformis , 6,894 ft., 11 June 1980, W. Weber & T. Kelso s.n. ( COLO!).