Xanthoparmelia plittii
Xanthoparmelia plittii photo by Bob Klips
Xanthoparmelia plittii apothecia photo by Bob Klips
DIAGNOSTIC FEATURES: Isidiate; pale brown underside; medulla K+ yellow turning red, stictic acid; compare with X. conspersa, which has a black underside and X. subramigera, P+ red in medulla.
ECOLOGY: Common and widely distributed in the eastern US; common in the unglaciated part of Ohio; found on acidic rocks but not on limestone or dolomite. As with other members of this genus, it prefers horizontal or sloping rocks, rather than vertical rock faces. Along with X. conspersa, this is the most commonly seen Xanthoparmelia in Ohio.