Dactylina arctica

Diane L. Haughland

Dactylina arctica (Richardso698n) Nyl., 1860 including ***Dactylina arctica* subsp. *beringica*** (C.D. Bird & J.W. Thomson) Kärnefelt & A. Thell, 1996

Common name	Mountain Butter-fingers	Code: DACTARC
Field Characters & Taxonomy Notes	Fruticose, club-like chlorolichen. Inflated balloon-like yellow to orangish hollow branches. May branch once or rarely twice but lacking numerous small side branches. Lacking pruina, isidia, soralia. Apothecia appear as brown discs on branch tips. Note: the taxonomic status of D. arctica subsp. beringica varies by author/source. Esslinger’s North American Checklist lists it as a species, D. beringica, as does Alberta’s conservation ranking system, ACIMS, and the Consortium of Lichen Herbaria. Other authors treat it as a subspecies, as does Index Fungorum. Given the two taxa are not morphologically distinguishable and chemistry is required to separate them, here we adopt the subspecies status of beringica.
Similar species	Dactylina ramulosa: typically less than 2 cm high, branching with abundant pruinose, small, rounded side-branches, the pruina sometimes resulting in a violet-brown color. Allocetraria madreporiformis: very similar in form, but more dichotomously branched, has a dense white medulla, and has fatty acids detectable by TLC and is PD-.
Ecology	In mountain habitats, both treed and open, in rock crevices and amongst moss and other lichens on soil.
Chemistry	Both subspecies: cortex K-, KC+ yellow, C-, PD-, UV- (usnic acid). D. arctica subsp. arctica: medulla K-, KC+ pink, C+ pink, PD-, UV- (gyrophoric acid). D. arctica subsp. beringica: cortex KC+ yellow to pink, C+ pink (usnic acid, gyrophoric acid), medulla K-, KC- or KC+ pink, C- or C+ pink, PD+ red, UV- (±gyrophoric acid, protocetraric acid, physodalic acid). If you don’t have chemistry, leave the identification at species level.
Molecular support
Links	Alberta Biodiversity Browser Consortium of Lichen Herbaria – D. arctica Consortium of Lichen Herbaria – D. beringica Ways of Enlichenment Photo Gallery
Gallery