Slideshow image
Lecanographa dimelaenoides (Egea & Torrente) Egea & Torrente
Family: Lecanographaceae
[Lecanactis dimelaenoides Egea & Torrente]
Lecanographa dimelaenoides image
Stephen Sharnoff  
Thallus: crustose, areolate, well developed, without a distinct prothallus areoles: angular, irregular, up to 500 µm thick, 0.3-2.5 mm across surface: whitish gray or gray, smooth or slightly granulose cortex: inconspicuous or thin, with mixed and intertwined hyphae, overlain by an epinecral layer 20-50 µm thick, medulla: white, variably thick, composed of mixed and loosely interwoven hyphae with many crystals of unknown nature (soluble in K) among the hyphae Ascomata: numerous, immersed or subimmersed, seldom adnate, scattered or crowded, rounded to somewhat irregular, 0.3-1.7 mm in diam., or lirellate 1-2.2 x 0.4-1.2 mm, simple or occasionally substellate disc: black, plane becoming convex; grayish pruinose, marginate at first, later becoming +immarginate exciple: well developed, dark brown, K+ dark green hymenium: hyaline, 110-130 µm tall, I+ pale red; paraphysoids: up to 1.5 µm thick, branched and anastomosing, not or slightly widened at apices, with slightly pigmented walls subhymenium: pale red-brown, 40-60 µm thick asci: slightly stipitate, grumulosa-type, with differentiated ring, 80-110 x 18-22 µm, 8-spored ascospores: hyaline, becoming brown only when old, transversely 7(-8)-septate, fusiform, 25-32 x 6.5-8(-9) µm; wall: somewhat swollen at the septa, surrounded by a thick gelatinous sheath Pycnidia: immersed, punctiform, unilocular or secondarily multilocular conidia: hyaline, straight, 6-9(-13) x 1-1.5 µm Spot tests: thallus K-, C+ pale red, P- Secondary metabolites: containing erythrin and traces of lecanoric and gyrophoric acid (HPLC). Substrate and ecology: on volcanic rock, coastal, moderately shaded, usually north-facing, vertical or almost vertical exposures, and underhangs, recesses, small cavities, and roofs of caves, ombrophobic (i.e., in areas sheltered from precipitation) World and Sonoran distribution: Baja California and southern California. Note: Lecanographa dimelaenoides is a very homogeneous species. See Egea and Torrente (1992 & 1994) for more details.