Rafflesia speciosa Barcelona and Fernando
A parasite of a species of Tetrastigma, a genus of forest lianas (woody vine) in the grape family (Vitaceae), Rafflesia is a genus of 18 species distributed in South East Asia. The flowers are large, with R. arnoldii from Borneo and Sumatra having gained the prestige of being the largest flower in the world with a diameter of nearly a meter.
This new species of Rafflesia was described and named by Dr. Julie F. Barcelona, a botanist from the National Museum in collaboration with a colleague from the University of the Philippines in Los Baños, Laguna. It is the third species of Rafflesia in the Philippines, all of which are endemic. One species, R. manillana, was found on Mt. Makiling in Laguna and described in 1841. It was also reported to occur in Samar, Leyte, and Mt. Isarog in the Bicol Region. The second species, R. schadenbergiana, is known only from the type collected from Mt. Apo in Davao in 1882 and described in 1885. There are no other specimens of it collected since then although there are unconfirmed sightings on the nearby Mt. Matutum.
The Rafflesia flower is rusty or reddish brown, composed of 5 petal-like structures (perigones) which are variously designed with whitish warts of different shapes. The perigones are subtended by several whorls of bracts that are covered by a cupule in young buds. Right next to the perigone lobes is a diaphragm, inside of which and can be viewed through a central orifice (opening), are processes attached to a dome-shaped central disk. One unique character of Rafflesia is its smell that resembles rotting meat so that when in bloom, flies are attracted to the flowers making them the best agents of pollination. The flowers are unisexual, i.e. they are either male or female. It is the country’s largest flower.