Anaptychia nevadensis
Anaptychia nevadensis is a species of foliose lichen in the family Physciaceae. It was described in 2022 from the north-western Great Basin of the western United States. It is an abundantly fertile, soredia-lacking member of section Protoanaptychia and differs from the Eurasian A. desertorum in having only scant whitish, longer ascospores on average, and frequent production of variolaric acid.
Taxonomy
The species was formally described as Anaptychia nevadensis with the holotype from the Jackson Range, Humboldt County, Nevada. The species epithet refers to its core range in Nevada. The authors segregated it from look-alike saxicolous forms of A. desertorum based on morphology, chemistry, and longer spores and conidia, and they supported the species rank with molecular analyses of ITS sequences.Description
The lichen forms small to mid-sized rosettes, usually 1.5–7.0 cm across, that sit loosely on the rock. The are short to moderately elongated, somewhat arched, and end in tightly inrolled, scalloped tips. The upper surface is pale to brownish gray and generally lacks the sugar-dust coating ; when present, the pruina is faint and mostly limited to the lobe tips. Coarse bristles are common near the growing tips, and the upper bears minute, single-celled bumps that look like tiny hairs under a microscope. The lower surface is pale, with a thin cortex only near the center of the thallus and becoming whitish and without a cortex toward the lobe tips. The species does not produce soredia.Fruiting bodies are usually abundant and often crowd together near the center of the rosette. They are round, about 0.5–1.5 mm in diameter, with a disk that is mostly free of pruina; a rim of thallus tissue persists around the edge. The sexual spores are typically slightly bent and measure about 23–35 × 12–17 μm. Tiny flask-shaped structures are immersed in the thallus and release asexual spores that are rod- to short-ellipsoid shaped, about 4.5–6.2 × 1.3–2.3 μm. Standard spot tests on the thallus are negative; thin-layer chromatography commonly detects variolaric acid, and weak K+ or KC+ reactions may be seen where that compound is concentrated.