Thallus fruticose sometimes compacted and subcrustose centrally, prostrate, closely attached to substrate by hapters over whole thallus area and not merely at base, base sometimes dying so that thalli form rosettes, branching isotomicdichotomous often strictly so, branches terete but tending to become dorsi ventrally compressed (in ), minute, even or uneven, brown to dark brown or black, matt to slightly shiny, usually concolorous except where attached to substrate. True lateral spinules, isidia, soralia and pseudocyphellae absent. Apothecia lateral, frequent to abundant, thalline exciple concolorous with the thallus, becoming excluded or if persistent, not incurved, sometimes ciliate, disc brown to black. Asci clavate, thick-walled, 8-spored. Ascospores ellipsoid, without a distinct epispore, hyaline at maturity, simple, 7-12 × 6-8 µm. Pycnidia common. Chemistry: Negative.