Thallus effuse, ochraceous, thin, continuous to weakly rimose, or exceptionally thicker and partly rimose-areolate with angular areoles c. 0.20.5 mm wide; prothallus not evident. In section to 100 m thick, exceptionally to 200 m; ecorticate, but with 512 m tall epinecral layer; medulla containing many mineral fragments; I+ weakly blue, but reaction often patchy or obscured by mineral fragments. Photobiont cells 58 m diam. or ellipsoid and to 9 7 m. Apothecia usually lirelliform, 0.251.15 0.20.4 mm, straight to curved, simple or with 1(4) branches, but occasionally rounded and Rimularia-like, sometimes even with a central umbo; black, usually becoming emergent and with raised margins and obtuse apices, sometimes a few lirellae are more innate with a slit-like disc, a seemingly narrower margin and acute apices; margin 0.070.3 mm wide, when raised often with a few transverse cracks; disc sunken, usually expanded but sometimes slit-like. Exciple cupulate, reddish brown, K+ brown-red pigment going into solution, N, 60195 m thick at base, 3774 m laterally and 60147 m at the apex; the upper part often spreading outwards (involucrellum-like) onto the surrounding thallus (or adhering portion of thallus). Hymenium c. 75100 m tall, hyaline, I+ blue; epithecium indistinct or present as a reddish brown layer c. 15 m tall. Hypothecium 2634 m tall, dilute red-brown. Paraphyses distinctly septate but not moniliform, 1.7 2 m wide, not swollen at apices, but apices sometimes surrounded by a brown-pigmented hood 33.5 m wide. Asci clavate, 6275 1724.5 m, 8-spored; in K/I with amyloid outer wall, and tholus with a thin amyloid apical cap and amyloid flanks (Trapelia-type). Ascospores (10)1217 (5.5)79 m, ellipsoid or broadly ovoid-ellipsoid, simple, hyaline, sometimes with a thin perispore.
Pycnidia usually present but rarely abundant, immersed, black, 60100 m diam.; wall reddish brown. Conidia narrowly bacilliform, 611(13) c. 0.8 m.

Chemistry. Thallus K, C, KC, P, UV; no substances detected by TLC.

Ecology and distribution. On siliceous rocks and stones, at altitudes from near sea-level to 1320 m. Lithographa graphidioides is a widely occurring species in the southern subpolar region at latitudes 42S to 5451S, being particulalry frequent in southern South Americ. It is known from Tasmania (Hertel & Rambold 1990) and has recently been reported from South Island, New Zealand (Galloway 2007), but is apparently absent from the Auckland Islands and Campbell Island.

Distribution in Google Earth

Search for this species on:
Click on a thumb-nail for a full size image.
Use cursor keys, or move mouse to side of image, for next (or previous) image