Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.

Thallus: areolate, up to 0.20 mm thick, with broad cracks, without a prothallus apparent areoles: convex, contiguous to dispersed, polygonal to roundish angular in outline, 0.3-0.5 mm wide, with pale flanks surface: dark greenish gray to gray-brown or brown, dull, minutely rough anatomy: upper cortex: indiscernible or up to 15 µm thick, indistinctly delimited against algal layer, with a brownish uppermost part, sometimes overlain by a thin epinecral layer; algal layer: subparaplectenchymatous, composed of small ±round, angular cells 4-7 µm in diam., with algal cells 9-15 µm in diam. filling most of the thallus Perithecia: usually situated at the margins of the areolae, globose to somewhat deplanate-ovoid, black, distinctly elevated, with convex apices, ostiolum usually in a small depression; exciple: (sub)globose, 0.20-0.28 mm wide, colorless to brown, 15-20 µm thick; involucrellum: completely enveloping the exciple, dark brown, upper part up to 35 µm thick, at base equally thick or somewhat thinner and often more diffusely pigmented; periphyses 20-25 µm long, simple asci: clavate, 60-70 x 15-20 µm, 8-spored ascospores: hyaline, simple, 13-18 x 6-7.5 µm, oblong or narrowly ellipsoid Pycnidia: unknown Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: epilithic, on siliceous rocks World distribution: Europe (described from Germany) Sonoran distribution: southern California. Notes: Verrucaria fraudulosa is very similar to V. minor, from which it differs in the larger perithecia, a thinner involucrellum which is usually closed at the base, larger asci and longer spores. The algal cells are also larger. The areoles of the Californian sample are convex as is regarded as typical for this species though the type material has flat to slightly convex areoles. Otherwise the specimen agrees very well with European material.

Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.

Thallus: cracked-areolate, forming small patches or extensive thalli up to several centimeters across, 0.2-0.3 mm thick, with rather acute fissures, sometimes bordered by a dark, compact or fimbriate prothallus areoles: angular, plane, 0.1-0.4 mm wide, with brown to black side-walls surface: gray to grayish brown, usually whitish gray pruinose, minutely wrinkled or roughened, thinly black-rimmed or not, dull anatomy: upper cortex: composed of few layers of 4-6 µm in diam. cells, with a 10-20 µm thick amorphous epinecral layer; algal layer: filling most of thallus, paraplectenchymatous, composed of cells 4-6 µm in diam., with algal cells 6-12 µm in diam.; basal layer: thin, brown to black, discontinuous, or lacking Perithecia: mostly at the margins of, or between the areoles, but also submarginally oder centrally immersed, apices flattened or slightly convex, level with surface of areoles or slightly emergent; exciple: subglobose, 0.15-0.22 mm wide, dark; involucrellum: contiguous with exciple, covering at least the upper two-thirds of the perithecium, mostly extending to exciple-base level and ± incurved beneath, laterally c. 30 µm thick; periphyses c. 20 µm long, simple asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid, 11-15(-16) x 5-7 µm Pycnidia: unknown Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: epilithic, on siliceous rocks at elevations from 50-1250 m World distribution: Europe and North America Sonoran distribution: southern Arizona (Cochise, Pima, and Santa Cruz Counties), Baja California, Baja California Sur, California, Chihuahua, and Sonora. Notes: Contrary to the European samples, the North American specimens of Verrucaria lecideoides are from siliceous rocks. The species is often confused or synonymized with Verrucaria beltraminiana which differs in having both larger perithecia and spores.

Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.

Thallus: areolate, 0.10-0.15 mm thick, usually less than 1 cm across, with comparatively broad fissures, with abrupt margins, without an apparent prothallus areoles: subangular, plane, 0.2-0.4 mm wide, with pale to dark brown sidewalls surface: brown, dull, epruinose, smooth to somewhat rough anatomy: upper cortex composed of 1-2 layers of brown cells, overlain by a c. 10 µm thick, amorphous epinecralic layer; algal cells: 7- 12 µm in diam., distributed over most of the thallus; without an alga-free medulla or dark basal layer Perithecia: situated at the edge of, or between the areoles, subglobose, black, distinctly elevated, with convex or slightly conical apices; ostiole inconspicuous; exciple: subglobose, 0.15-0.20 mm wide, brown, 15-20 µm thick; involucrellum: appressed to the exciple, extending to exciple-base level and incurved beneath, apically and laterally c. 50 µm thick, thinner at base; periphyses 15-20 µm long, simple asci: clavate, 45-55 x 14-18 µm, 8-spored ascospores: hyaline, simple, ellipsoid, 11-15 x 5-7(-8) µm Pycnidia: unknown Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: epilithic, on calcareous rocks and sandstone World distribution: Europe, North Africa, Australia Sonoran distribution: two collections known from Arizona (Coconino and Yavapai Counties). Notes: The Sonoran specimens of Verrucaria minor agree well with the European collections. This taxon is regarded as a variety of Verrucaria lecideoides by most authors, but it merits species rank. It is distinguished from Verrucaria lecideoides by its smaller thalli with epruinose surfaces and distinctly emergent to almost superficial perithecia. Verrucaria fraudulosa differs in having convex areoles, larger perithecia, and longer spores.