Fossil mushrooms - Protomycena electra. Hibbett, Grimaldi, & Donoghue gen. et sp. nov. (Fungi Basidiomycota). This mushroom was found in Dominican amber and is ~15-30 million years old. It is remarkable not only for its exquisite preservation, but also for its striking morphological resemblance to extant mushrooms in Mycena and other Tricholomataceae. Protomycena is one of only three known fossil mushrooms.