High Quality Content by WIKIPEDIA articles! Lactarius rupestris is a species of mushroom in the Russulaceae family. Described as a new species in 2010, it is known only from the semi-arid region in the National Park of Catimbau of Brazil. The mushroom is characterized by a stout fruit body with a smooth and sticky orange cap up to 7 cm (2.8 in) in diameter. The gills on the underside of the cap are closely spaced and frequently anastomosed. The stem is 35–45 mm (1.4–1.8 in) long by 18–21 mm (0.71–0.83 in) thick. The mushrooms exude a sparse cream-colored latex when cut or injured.