Per Malachowski: Thallus loosely adnate to pendulous, 2-10 cm long, narrowly foliose to subfruticose, fairly stiff, usually smooth, greenish gray to ashy colored, or rarely becoming brown or blackish brown at the margins, and finally throughout; lobes long and narrow, hollow, dichotomously branched and becoming imprecated, somewhat ascending towards the margins; lower surface brownish black to black, wrinkled, no rhizines, perforate near the lobe apices and sometimes in the lobe axis; medulla thin, dark brown to black; apothecia common, middle-sized to large, 3-14 mm in diam., sessile to subpediculate, the disk concave, chestnut-brown or lighter, the exciple entire to irregular. The algal host is Protococcus. Hypogymnia inactiva is morphologically very similar to Hypogymnia imshaugii, which also occurs in this location. It is distinguished by its thin black medulla where the other species has a white medulla.
Merav Vonshak
2017-11-00
2017/11/24 2:02 PM PST
United States of America, California, Sonoma County, CA, USA