Exidia glandulosa, also known as black witches butter is a black jelly-like fungus which grows on hardwoods.   In Oakland, it is commonly found on coast live oak.

 

Exidia glandulosa by Alan RockefellerExidia glandulosa by Alan RockefellerExidia glandulosa by Alan RockefellerExidia glandulosa basidia 400x by Alan RockefellerExidia glandulosa spores 400x by Alan Rockefeller

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