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Lecanactis dubia G. Merr.
Family: Roccellaceae
Lecanactis dubia image
Thallus: crustose, mostly endphloedal, continuous, poorly delimited, very thin (c. 80 µm thick), filmy, without a visible prothallus surface: white, farinose, effuse medulla: not differentiated Ascomata: rounded to somewhat elongated, not branched, sessile to substipitate, 0.2-0.5 mm in diam. disc: black, plane or somewhat convex or occasionally slightly concave, slightly pruinose and roughened margin: not very evident except in the smaller ascomata, somewhat prominent, smooth to granulose or verrucose exciple: dark brown internally, with hyphae visible in outer part, branched and interwoven, with reddish walls, occasionally encrusted with granules or crystals insoluble in K hymenium: hyaline, 50-60 µm tall, I+ pale blue; paraphysoids: 1-1.5 µm thick, enlarged to 4-5 µm wide apically, pigment in outer part, reticulate subyhymenium: hyaline or pale yellow, 10-15 µm thick hypothecium: dark-brown to black asci: clavate, 40-50 x 11-16 µm, 8-spored ascospores: hyaline, transversely 3(-4) septate, fusiform, with thin and uniform walls or somewhat enlarged at the septum, 16-23 x 3-4 µm Pycnidia: not seen Spot tests: thallus K-, C-, KC-, P- Secondary metabolites: none detected. Substrate and ecology: on bark in coastal areas World and Sonoran distribution: Santa Catalina Island, California. Notes: The only record of L. dubia is that of the type material collected at Santa Catalina Island, California (Tehler and Egea 1997).