Laricifomes officinalis is a wood-decay fungus in the order Polyporales. It causes brown heart rot on conifers, and is found in Europe, Asia, and North America, as well as Morocco. It is commonly known as agarikon, as well as the quinine conk due to its extremely bitter taste. DNA analysis supports L. officinalis as being distinct from the genus Fomitopsis. "The decay is common only in a few old-growth stands. The conks were once collected extensively for production of medicinal quinine.
