Slideshow image
Xanthoparmelia tuberculata (Gyeln.) T.H. Nash & Elix
Family: Parmeliaceae
Images
not available
Thallus: subcrustose to very small foliose, adnate to tightly adnate, 1-4 cm in diam., irregularly lobate lobes: sublinear to subirregular, elongate, plane to subconvex, separate and contiguous, 0.2-1 mm wide, not lobulate; apices: subtruncate, smooth to crenate, eciliate upper surface: yellow to yellow-green, darkening with age, smooth but becoming strongly rugose, cracked and areolate with age, dull to slightly shiny, epruinose and emaculate, without soralia, isidia, or pustulae medulla: white, with continuous algal layer lower surface: pale to medium brown, plane, moderately rhizinate; rhizines: pale to dark brown, simple, 0.05-0.1 mm long Apothecia: common, sessile to sub-stipitate, 1-2 mm wide, laminal on thallus; disc: cinnamon-brown to dark brown; margin: smooth, pruina absent asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid, 8-9 x 4-5 µm Pycnidia: common, immersed conidia: bifusiform, 5-6 x 1 µm Spot tests: upper cortex K-, C-, KC-, P-; medulla K-, C-, KC-, P+ red Secondary metabolites: upper cortex with usnic acid (major); medulla with fumarprotocetraric acid (major), protocetraric acid (minor), confumarprotocetraric acid (minor), ±caperatic acid (major), ±norcaperatic acid (minor). Substrate and ecology: on acidic rocks, often in open or partially shaded habitats World distribution: North America Sonoran distribution: common at intermediate elevations in Arizona, Chihuahua and Sonora. Notes: Previously this species was included in a broader concept of X. novomexicana (Hale 1990) but we believe it can be distinguished by the smaller, more tightly adnate, subcrustose thalli (1-4 cm vs. 4-20 cm wide), the narrower lobes (0.2-1 mm vs. 0.8-3 mm wide) and shorter ascospores (8-9 µm vs. 10-11 µm long).