Brassia gireoudiana
Native to Costa Rica and Panama, this perennial orchid grows on trees in forests with distinct rainy and dry seasons. In southern Costa Rica, it occurs on Pacific slopes between about 1,600 and 3,300 feet. Its green flowers have brown markings and pale lips, with long, slender petals and sepals giving them a spidery shape. Individual flowers can reach about 10 inches from top to bottom. Thickened stems called pseudobulbs store water and bear one or two leathery leaves. Photographed in Panama.