Lecanactis
Crust lichens containing a trentepohliate alga; thallus thin, scurfy, sorediate, verruculose, or immersed; apothecia round to elongated, black, often with white or yellowish pruina on the disc and/or rim; rim prominent and persistent, formed of cylindrical hyphae individually coated in dark brown pigment masses; hymenium colourless except in upper portions, formed of densely branched and anastomosing paraphyses embedded in gel; asci narrowly clavate to cylindrical, with a distinct stalk at the base, with a moderately thickened, IKI+ light blue ascus containing a dark blue ring (appearing as two dashes positioned above the ocular chamber); spores 8 per ascus, elongate-fusiform, with 3-7 transverse septae.
Notes: Lecanactis in northwestern North America is much in need of study. Names based on European types may be misapplied here. The distinction between Lecanactis and Cresponea is difficult to apply owing to specimens intermediate between these two genera.
References: Egea & Torrente 1994; Ryan & Tehler 2004.
Lecanactis megaspora (G. Merr.) Brodo
Thallus whitish or pale grey, scurfy, often inconspicuous or immersed; apothecia 0.5-1.5 (‑2) mm wide, jet black, but the disc generally with at least some whitish pruina, the rim prominent and persistent, usually lacking pruina; spores 25-48 × 3.5-6 µ; pycnidia conspicuous, barrel-shaped, black, tipped in a C-, white (the conidial mass); conidiospores (macroconidia) 11-17 × 2-3.5, straight or somewhat curved.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: On Thuja bark in humid forests. Lower elevations.
Similar Species: Lecanactis abietina has pycnidia that react C+ red at the tip.
Local Status: Rare.
Notes: Lecanactis salicina may be a better match with our material, but local specimens fit both species poorly.