Eriogonum microtheca var. arceuthinum

Subshrubs, 0.5-0.7 × 1-1.5 dm. Stems: caudex spreading; aerial flowering stems 0.1-0.3 dm, glabrous. Leaves: blade linear, 0.5-0.8 × 0.05-0.1 cm, densely white-tomentose adaxially, sparsely floccose or glabrous and green adaxially, margins revolute. Inflorescences 0.5-2.5 cm; branches sparsely floccose or glabrous. Involucres 2-3 mm, glabrous. Flowers 1.5-2 mm; perianth white. Achenes 1.5-2 mm.

Flowering Jul-Sep. Volcanic slopes and cliffs, oak and pinyon-juniper woodlands; 1900-2100 m; Nev.

Variety arceuthinum was gathered originally by Carl Purpus in the 'Juniper Mountains' in 1898. It is uncertain whether his collection came from southwestern Iron County, Utah, or from southeastern Lincoln County, Nevada. A single, sterile collection (Shultz & Shultz 7109, BRY, GH) with dubious label data supposedly was found in Nevada, and a second collection from that state, made by A. Jerry Tiehm and sent to L. M. Schulz, apparently has been lost.