Geissospermum reticulatum (Apocynaceae Kichwa: Challua Caspi ) is a relatively scarce tree found in old growth forest used to alleviate stomach problems and muscle pain. The Kichwa name Challua Caspi derives from the bark’s resemblance to the coloring and texture of a sucker fish called “challua”. Preparation: Before harvesting, the spirit owner of the tree is asked for permission cut the bark. Sections of bark are cut from the east and west sides of the tree (the sides where the sun hits the tree). The bark is then boiled down into a thick liquid to be drunk as a tonic. For a more potent remedy challua caspi is mixed with the bark of amarun caspi (Cespedezia spatulata). The taste of Challua Caspi is bitter. Biting into its bark tastes like biting into a penicillin capsule. Many hardwoods have bitter alkaloids in their bark. Runa generally believe that their ancestors lived longer and had more endurance than people have now because they drank daily doses of tinctures made from bitter trees. Principle among these were chuchuwasu, Challua caspi, and amarun caspi. Drinking bitter tea made from the bark of these hardwood imparted the long life and the strength of the hardwoods.