The Oyster Mushroom was first described scientifically in 1775 by Dutch naturalist Nikolaus Joseph Freiherr von Jacquin (1727 – 1817) and named Agaricus ostreatus. (In the early days of fungus taxonomy most of the gilled mushrooms were included in the genus Agaricus.) In 1871 German mycologist Paul Kummer transferred the Oyster Mushroom to the genus Pleurotus (a new genus that Kummer himself had defined in 1971), giving it its currently accepted scientific name.
Three different species of fungi: Pleurotus ostreatus, Pleurotus pulmonarius, and Pleurotus populinus are all commonly known as Oyster mushrooms. The only true difference between these three species is the season in which they grow. Oyster mushrooms get their name from an uncanny resemblance to fresh-shucked oysters.