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A previously unreported lichen (Aberratus uittathallus sp. nov.) with peculiar characteristics is described. Its foliose growth form, cyanobiont, and homoiomerous, gelatin-rich medulla were most consistent with membership in the order Peltigerales, although it is not an obvious member of a known family. Its size (66 cm long) and off-white, ribbon-like thallus, which becomes shrunken, translucent, brittle, hydrophobic, light tan, and ostensibly dead when dried, are anomalous characteristics of lichens in general. No means of reproduction was identified, except possibly fragmentation. The organism's anomalous characteristics, distribution on the type locality, and rarity were hypothesized to represent the results of a recent fortuitous lichenization. [ABSTRACT FROM AUTHOR]

Large-scale fires are anticipated to increase in frequency in the boreal forest under global climate warming scenarios. To understand concomitant responses by wildlife to fire-induced habitat changes, fecal pellet counts were used to assess Snowshoe Hare (Lepus americanus) use of four age-classes of boreal forest after fire in central Yukon, Canada. Use of stands across a chronosequence of 8-177 years was bimodal. Post-fire Trembling Aspen (Populus tremuloides) stands ≤20 years old had greater densities of Snowshoe Hare pellets (median 156 pellets/dam²) than Trembling Aspen stands 21-70 years old, mixedwood stands 71-120 years old (<17 pellets/dam²), or Western White Spruce (Picea albertiana) -dominated stands 121-170 years old (71 pellets/dam²). Forty stand-level compositional and structural variables were assessed as possible predictors of Snowshoe Hare pellet densities. Multidimensional scaling was used to identify variables (n - 10) that were most strongly related to pellet densities and was followed by multiple regression. Canopy cover of Trembling Aspen <50 cm tall and Western White Spruce si m tall, and deadfall depth, in combination, were the best estimators of Snowshoe Hare pellet densities among stands in the chronosequence (P <0.001. 64.5% variance explained). Although Trembling Aspen <50 cm tall explained the most variance, its canopy cover did not exceed 10%. More Trembling Aspen cover <50 cm tall and greater deadfall depths within the chronosequence were associated with stands ≤20 years old. Peak Snowshoe Hare use occurred in early (≤20 years old) rather than mid-successional (21-120 years old) stands, contrary to use patterns reported elsewhere. The lack of tall understory shrubs likely limited the use of mid-successional stands. [ABSTRACT FROM AUTHOR]