Pertusaria xanthodes

Instead of the usual 8 spores per ascus, P. xanthodes only has two. These are very large and have margins that appear to be winged and ribbed, especially when not quite mature. The asci are typically cylindrical as shown. The lower ascus is immature with spore development barely initiated.

Asci of this genus have very thick walls which often appeared to be have several layers. In this ascus one spore has been aborted.