Karinomyces (Pilocarpaceae), a new genus for the Appalachian endemic Schadonia saulskelleyana

Schadonia saulskellyana is an endemic crustose lichen narrowly restricted to the fragmented high elevation spruce-fir forests of the central and Southern Appalachians. These communities are predicted to face rapid changes in temperatures and precipitation which may impact habitat suitability of many species including S. saulskellyana. The placement of S. saulskellyana within the family Pilocarpaceae was investigated through newly generated molecular data and phylogenetic analysis. Both Bayesian and maximum likelihood approaches strongly supported S. saulskellyana as monophyletic, separate from S. fecunda and all other sequenced lineages in the Pilocarpaceae. This, combined with previously documented phenotypic differences and unique biogeographic patterns, supports recognition of S. saulskellyana as a distinct genus which is described here as Karinomyces. Given the restricted distribution and potential conservation concern for this unusual taxon, habitat suitability was modeled using Species Distribution Modeling (SDM) and compared under multiple future climatic scenarios. These analyses did not predict a significant future loss in total area, except under the most extreme climate scenario, but did predict significant declines in the areas of highest suitability. Disjunct populations at the range periphery appear especially vulnerable to local extirpation. The predicted loss of highly suitable habitat and potential for extirpation along the peripheral range underscore the urgent need for further study of Karinomyces and high-elevation spruce-fir forest lichen communities generally.