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Santessoniella arctophila (Th. Fr.) Henssen (redirected from: Parmeliella arctophila)
Family: Pannariaceae
[Parmeliella arctophila (Th. Fr.) Malme]
Santessoniella arctophila image
Ahti, T., Jorgensen, P. M., Kristinsson, H., Moberg, R., Sochting, U., & Thor, G. (2007). Nordic Lichen Flora. Vol. 3. Cyanolichens. Uddevalla: Nordic Lichen Society: 112.

Thallus as scattered granules over moss, occasionally aggregated and/or elongate, to 0.3 mm diam., often rather wrinkled, semigelatinous, greyish to dark brown, with cortex 8-16 µm thick, usually of a single layer of cells; internal hyphae forming a reticulate pattern around the clusters of Nostoc which fill the internal parts.  APOTHECIA common, orange-brown, often convex, 0.3-1(-2) mm diam., with often excluded paler marginSpores simple, colourless, ellipsoid, 15-20 X 8-10 µm, with slightly warted exospore.  CONIDIOMATA rare, wart-like, brownish-black; conidia bacciliform, 4-5 X 1 µm.

Chemistry.  No secondary substances (by TLC).

Habitat.  Terricolous on mosses or debris in alpine heaths.

Distribution.  Arctic-alpine, circumpolar.  Gr. F. Kn Enl I: IMi IAu INv INo. N: Ho SF ST Tr 0Fi.  AI: Bi Sb. S: Upl Jmt AsL LyL PL LuL TL.

Note:  An easily overlooked, but characteristic species, in the field easily mistaken for an Arctomia which has a less gelatinous thallus, and in the microscope is easily distinguished on its fusiform spores.

S. arctophila is a quite variable species, particulary in thallus development.  The type specimen has a very poorly developed thallus, appearing as a patchy granular crust over the mosses.  Henssen (1997) has separated two varities, var. glomerulosa and var. terricola, both of which have better developed thalli than the typical form, the first with agglutinated lobes, the second with more elongate, partly branched lobes.  Their status is in need of further evaluation when more material becomes available.  Lynge (1926) distinguished a var. microspora Lynge on material from Bjørnøya. The small spores appear to be result of poorly developed apothecia, and this taxon is thus not worth maintaining.  

The generic placement of this species has been difficult, and it does not fit into any of the genera it has been placed in.  Even its recent transfer to Santessoniella is doubtful, as it is obviously not congeneric with the type of this genus.  It may need to be placed in a separate genus.  

Thompson, J., 1984. American Arctic Lichens: The Macrolichens.
Thallus granulose, the granules 0.12-0.3 mm thick, spherical, not branched but coalescing to form a continuous crust, swelling when wet and drying into wrinkled clumps, gray with brown suffusion; upper cortex 8-12 /jl, para-plectenchymatous; algae glomerulate in a dense medulla; underside attached by hyphae; although resembling the thallus of Pannaria pe-zizoides in structure, this lacks the bordering squamules of that species. Apothecia adnate, to 0.7 mm broad; margin lecideine, narrow, entire, paler than the disk, not gelatinous; disk flesh-colored, flat to convex, smooth, epruinose; epithecium brown, not inspersed; hymenium hyaline, 75-95 with compact plug-like apical apparatus; paraphyses 1.5 μ thick, unbranched; spores ellipsoid, the outer wall smooth both ends round, 15-50 X 7-12 μ.

Reactions: hymenium 1+ blue, turning wine-red.

Contents: unknown.

This species grows over mosses on soil. It is arctic and alpine, probably circumpolar. In North America it is exceedingly rare. It was first reported from the Mt. McKinley area in Alaska by W. A. Weber (1965). J0rgensen (1978:111) expressed doubt that this species is in the Pannariaceae, suggesting it may be possibly referred to the Collemataceae or Placynthiaceae on account of the thallus texture.