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Miriquidica verrucariicola (B. D. Ryan) K. Knudsen & Kocourk. (redirected from: Lecanora verrucariicola)
Family: Lecanoraceae
[Lecanora verrucariicola B.D. Ryan,  more]
not available
Life habitat: lichenized, lichenicolous at least when young Thallus: crustose, epilithic, forming ±round to irregular, well-delimited patches, up to 4 cm in diam., areolate or composed of discrete verrucae, marginly indistinct to distinctly lobate; lobes: 0.15-1 mm wide, up to 1.5 mm long areoles: distinctly separated from one other, rounded, elongate to irregular, convex to hemispherical or ±globose, rarely weakly peltate surface: yellow-brown, chestnut brown to dark brown, sometimes black, glossy cortex: phaenocortical, inspersed with fine to medium-sized (c. 10 µm wide) crystals, with (5-)10-25 µm thick epinecral layer and a 20-50 µm thick, brown upper cell layer, apices of cells with a dark brown cap medulla: hyaline, with thick-walled, septate hyphae, inspersed with fine crystals photobiont: green algae, composed of globose cells, 7-15 µm in diam. (probably Trebouxia sp.) Apothecia: abundant, grouped or sometimes scattered, present all over the thallus, immersed, erumpent to sessile, sometimes constricted at base, 0.2-0.9 mm wide, shiny or dull, clearly marginate disc: somewhat concave to often plane, rarely somewhat convex, dark brown to black, epruinose margin: concolorous with the thallus, entire to flexuose, becoming crenulate, often somewhat raised, up to 0.15(-0.2) mm wide amphithecium: with a phenocortical cortex and a somewhat similar structure as the thallus, but without crystals parathecium: absent laterally, rarely developed as a small rim below the hypothecium epihymenium: dark greenish olive, without crystals, K-, N+ pale red hymenium: hyaline, 45-65 µm tall; paraphyses: thin, below 1.5-2 µm in diam., at the top abruptly widened to 5 µm, sometimes sparingly branched, lax to slightly conglutinated in water, dark olive greenish to black apically hypothecium: hyaline, of variable thickness, composed of thin, intricate hyphae, interspersed with fine crystals in its lowest part asci: cylindrical to slightly clavate, Lecanora-type, 20-30 x 9-14 µm, with a clear amyloid cylinder, which does not reach the top of the ascus, 8-spored ascospores: hyaline, simple, ellipsoid to oblong-ellipsoid, 6-10 x 2.5-3(-3.5) µm, thin-walled Pycnidia: not always present, dark brown to black, conspicuous, 60-100 µm in diam. conidia: filiform, curved, 14-16 x 0.5-0.7 µm Spot tests: I-, K-, C-, KC+ pink to red-violet, P- Secondary metabolites: (thallus): lobaric (submajor to major), oxolobaric (major), and norlobaric (minor) acids, by TLC and HPLC. Substrate and ecology: in maritime, arid to semi-arid habitats, initially lichenicolous on Dimelaena radiata, Tephromela atra (= T. nashii?) or Verrucaria sp., eventually independent on acidic rocks World and Sonoran distribution: Baja California and southern California (Channel Islands). Notes: Protoparmelia ryaniana is characterized by its placodioid, lichenicolous, pale to dark brown, shiny thallus with crowded, lecanorine apothecia, in combination with relatively small ascospores, the presence of lobaric and oxolobaric acids (major), and the cortex structure, a brown-colored layer of hyphae. Specimens referenced by Ryan et al. (2004) under Protoparmelia as 'initially classified as Lecania' (Vol. II, p. 426) as well as other specimens referenced by Rambold et al. (2004) under Miriquidica mexicana as having lobaric acid, narrow spores and growing on Tephromela atra agg.' belong to P. ryaniana. [The tentative, unpublished names Lecania lichenicola or Lecanora lichenicola may have been used for P. ryaniana on some herbarium specimens.] Protoparmelia ryaniana is most likely to be confused with Miriquidica mexicana. That Miriquidica species is distinguished by its lecideine apothecia, wider ascospores, longer pycnoconidia and by the presence of miriquidic acid rather than the lobaric acid aggregate. A somewhat similar placodioid species with lobaric acid is Lecanora brattiae, which may have a similar color but is usually light gray and often pruinose. Moreover L. brattiae is always rosette-forming and its apothecia are crowded in the thallus center and not scattered in groups over the whole thallus as in P. ryaniana. Associated, independent lichens occurring in the same microhabitat include Acarospora sp. (yellow), Buellia dispersa, Caloplaca sp. Dimelaena cf. californica, D. weberi, and Niebla sp. One additional lichenicolous fungus has been found in P. v.d. Boom 24971, tentatively identified as Endococcus aff. perpusillus Nyl. The material is scanty and more material is needed to determine the precise identity; consequently, a separate description of that species has not been made.
Thallus: thin, tight, areolate to subsquamulose; prothallus: absent areoles: scattered, 0.3-0.7 mm across, roundish to irregular, plane to convex, sometimes the peripheral ones forming short lobes surface: matt to shiny, light to moderate orange, light brown, or light or moderate yellowish brown or grayish yellow to light grayish to yellowish brown or moderate yellowish brown, without paler edges; soredia: absent cortex: (25-)30-50 µm, the upper part pale yellow-brown, interspersed with fine brownish granules soluble in K; lumina 2-7 x 1-1.5 µm, round to short, unoriented, to anticlinal (hyphal bundles); epinecral layer: 10-15 µm medulla: white, the hyphae c. 5 µm wide, with covering of fine grayish granules; algal layer: 50-75 µm thick; algal cells 10-15(-20) µm in diam. Apothecia: lecanorine, to 0.7-1 mm diam.; disc: plane to slightly convex, bare, dark olive brown to dark grayish yellowish brown to brownish black, paler when wet margin: concolorous with thallus, level to slightly raised, entire, 0.1 mm wide, soon becoming excluded; parathecial ring: absent or inconspicuous, concolorous with disc amphithecium: 85-90 µm thick; cortex: c. 30 um thick, interspersed with fine brownish granules (soluble in K), the hyphae +anticlinal, outer 1-2 cells brown-walled, 3-4 µm wide; epinecral layer 5 µm; algal cells abundant throughout inner part of amphithecium and extending below hypothecium exciple: indistinct, hyaline epihymenium: 5-7 µm thick, with some fine dark granules (unchanged in K), with brown spots (bundles of paraphyses tips) hymenium: hyaline, 35-40 µm tall, I+ blue; paraphyses: +loosely coherent, simple to forked, c. 1.5 µm wide, the tips +capitate, to 5 µm wide, brown-walled; subhymenium: c. 15 µm thick, indistinct, hyaline; hypothecium: 125-150 µm thick, hyaline; hyphae conglutinate, unoriented asci: c. 30 x 8-10 µm, the tholus I+ blue, resembling the Bacidia-type, but axial mass and ocular chamber rather indistinct; 8-spored, the spores irregularly biseriate ascospores: 0-1-septate (septum rather thin and indistinct), (11-)12.6-14 x 4.2-5.6(-7) µm, narrowly ellipsoid Pycnidia: few, immersed, c. 125 µm in diam., the ostiole brown conidia: filiform, curved, 15(-20) x c. 0.5 µm Spot tests: all negative Secondary metabolites: CE-71: pale yellow-gray phenolic 4A, 5-6B, 6C; terp 5A, 6C (same as in CE-69) [contaminant?]. Substrate and ecology: on Verrucaria sp. (recognizable by its white, black-edged areoles, giving a distinctive mosaic appearance), over acidic rocks in coastal areas (supralittoral to terrestrial zone) World and Sonoran distribution: southern California (Channel Islands) and Baja California. Notes: Lecanora verrucariicola is characterized by its brown areolate to subsquamulose or weakly lobed, corticate thallus, lecanorine apothecia with dark brownish discs and disappearing thalline margin, clumped, brown-capitate paraphyses, narrowly ellipsoid, 0-1-septate ascospores, and its lichenicolous habit, with apparent restriction to a single species of coastal Verrucaria. The placement of this species is very uncertain at present. Features of the asci, paraphyses and spores originally suggested that this species was a Lecania; however, according to van den Boom (pers. comm.) it does not belong in that genus, and for the present should be treated within Lecanora s. lato. The ascus type, lacking the non-amyloid apical cushion, separates L. lichenicola both from Protoparmelia, which it resembles especially in having a brown thallus, and Lecanora s. str., but is described under the broad concept of Lecanora used here. It may be related to Lecanora brattiae, which can also occur in association with the black-and-white Verrucaria, but that species differs especially in having distinct marginal lobes and +pruinose thallus and discs.