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Mobergia angelica (Stizenb.) H. Mayrh. & Sheard (redirected from: Dimelaena angelica)
Family: Caliciaceae
[Dimelaena angelica (Stizenb.) Hale & W.L. Culb.,  more]
Mobergia angelica image
Thallus: areolate; areoles: 0.55-1.2 mm wide, plane or markedly convex, marginal areoles may becoming sub- lobate upper surface: light gray to ochraceous, shining, dull or pruinose Apothecia: frequent, 0.5-1.3 mm diam., usually one per areole, innate becoming sessile or not disc: black or pruinose, plane or becoming convex margin: thalline, prominent, concolorous or darker than thallus, entire or almost cryptolecanorine epihymenium: with oxalate crystals and secondary metabolites, K+ red with crystals, P+ yellow or orange ascospores: (14-)1718.5(-21.5) x (7-)8.5-9.5(-11) µm; distinct narrow torus visible in minority of spores Pycnidia: immersed in thallus, with slightly raised ostioles conidia: hyaline, 3-4 x 1.5-2 µm long Spot tests: K+ yellow to red with crystals, C-, P+ yellow Secondary metabolites: norstictic acid in epihymenium, disc pruina, medulla and cortex. Substrate and ecology: on acidic rocks, basalt, rhyolite, calcareous tufa, calcareous sandstone and more rarely on soil World distribution: southwestern coastal North America Sonoran distribution: southern California, Guadalupe Island, Baja California, Baja California Sur from sea level to 800 m. Notes: The variable thallus morphology is at least explained by differences in substrate, plants growing on rock bearing relatively plane areoles whereas those growing on soil have more convex areoles. Material growing on calcareous tufa is densely pruinose due to oxalate deposition in and on the surface of the thallus and epihymenium giving the thalli a light gray color. In some aspects the thalli resemble those of Dimelaena weberi and Thelomma mammosum.