Coelogyne rochussenii

Native from peninsular Thailand through the Malay Archipelago, it is an epiphytic orchid that grows on tree trunks and branches in riverine and swamp forests. It forms clumps of narrow, ribbed swollen stems called pseudobulbs, each bearing a pair of pleated, oval green leaves. Its hanging flower clusters open at about the same time, with pale yellow sepals and petals and a faint lemon scent. The flowers partially close at night and reopen in the morning. Although the species occurs across a broad region, its wild populations in Singapore are Critically Endangered. Photographed in Florida.