Of the largest family of Orchidaceae, only a single species is known to flower at night. Its called Bulbophyllum nocturnum. Please find the news from BBC attached.
http://www.bbc.co.uk/news/science-environment-15818662 Plant is recently described by Andre and Prof. Vogel so its not yet there on the monocot list. Regards Pankaj -- ********************************************************************** "Taxonomists getting Extinct and Species Data Deficient !!" Pankaj Kumar Ph.D. (Orchidaceae) Conservation Officer Office: Flora Conservation Department Kadoorie Farm and Botanic Garden (KFBG) Corporation Lam Kam Road, Tai Po, New Territories, Hong Kong. Residence: 36c, Ng Tung Chai, Lam Tseun Tai Po, New Territories, Hong Kong. email: [email protected] [email protected] [email protected] Phone: +852 2483 7128 (office - 8:30am to 5:30pm) +852 9436 6251 (mobile)

