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Remarks (internal):This new species is very closely related to Tricharia umbrosa Kalb & Vezda described from Brazil (Kalb & Vezda 1988). Both share the sessile, brown-black apothecia and 1–2-spored asci. However, the ascospores in T. umbrosa are much larger (50-65 — 20-25 µm), while the thallus setae are distinctly shorter (0.2-0.4 mm). Also, the apothecia of that species are larger on average (0.2-0.4 mm diam.). The collections from Louisiana are sterile but agree well with the other material in the setae and hyphophores; they were misidentified as T. melanothrix Fée by Tucker (1981). Tricharia melanothrix is not known from North America. 
Description type:Original description 
Description:Thalli corticolous, crustose, continuous, 10–30 mm across, 10–20 µm thick, with a cartilaginous, corticiform layer, smooth to slightly uneven, lacking calcium oxalate crystals, pale greenish to whitish gray, nitidous, with abundant black setae; setae 0.8–1 mm long, 30–50 µm wide at base. Photobiont trebouxioid, cells 6–8 µm diam. Apothecia sessile, lecideine, round, 0.15–0.25 mm diam., 80–100 µm high; disc concave, dark brown; proper margin distinct, prominent, black. Excipulum para¬plectenchymatous, 10–30 µm broad, brown, externally dark brown. Hypothecium 5–10 µm high, colorless; epithecium 3–7 µm high, pale brown. Hymenium 30–50 µm high, colorless. Asci clavate, 30–45 — 15–22 µm. Ascospores 1–2 per ascus, ellipsoid to subglobose, muriform, with slight constrictions at the septa, 20–25 — 12–18 µm, 1.2–1.8— as long as broad, colorless. Hyphophores setiform with acute apex, 0.6–1 mm high, black. Diahyphae inserted apically, branched throughout, shallowly moniliform with fusiform segments, terminal segments ellipsoid, 6–12 — 1.5–2.5 µm. Chemistry: no substances detected by TLC. 
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