Some Monopodial Orchid Genera with a single species
Monopodial orchid species are those which usually grow in only one direction, upwards. Bear in mind, that the plants can still branch from along their stems and produce baby plants from their base. Many monopodial genera are well known such as Vanda, Phalaenopsis and Renanthera, but for this week’s article we would like to show some lesser-known genera, that, at least in the Philippines, have only a single species.
Over recent years much re-classification has been occurring amongst orchid genera, because of DNA studies, and we will use both, the “older” generic concept, and mention the new name.
Ascocentrum aurantiacum subsp. philippinense, can also be known as Vanda aurantiaca subsp. philippinensis, is endemic to the Philippines and has been found mainly in Luzon, and throughout much of Mindanao. We would be very happy to know of findings of this species in Visayas. The plant is known to occur in fairly shaded habitat in the mountains of central Luzon. Usually the flowers are bright orange, with a deep red anther cap. We have recently seen an individual from northeast Mindanao, which has greenish-yellow blooms. The upright inflorescences bear many small flowers. This species occurs from low elevations to about 1,200 meters elevation above sea level.
Ascoglossum calopterum can also be known as Renanthera caloptera. This species also occurs on the island of New Guinea, and the neighboring islands of Maluku. In the Philippines, it is only known from the island of Dinagat, but one could safely assume that it would also be found in the south of the island of Mindanao, or in the neighboring Eastern Visayas. The upright, branching inflorescence produces many interesting purplish blooms, in which the floral segments usually reflex backwards. Plants have been observed where the colour of the foliage is quite purplish.
Ceratocentron fesselii is the most wonderful, miniature species, known only from a small area in the mountains of Central Luzon, to which region it is endemic, and known from no other place on earth. The plant is barely 4 cm across the span of its slightly leathery leaves, but this little plant can produce two inflorescences each bearing up to four blooms about one centimeter across. The color varies from red, to bright orange, to yellow. In Australia, Jim Cootes has seen flasks of this species, where the plants inside are blooming in their very sheltered enclosure. This is not a species for the lowlands. Megalotus bifidus can also be known as Robiquetia bifidus. This delightful species has leaves that are reminiscent of velvet, on their upper surface. The inflorescence is pendulous and bears many small yellowish-green flowers, and the tip of the white labellum is forked, much like the tongue of a snake. This species is found throughout much of the Philippines, where it grows as an epiphyte at elevations of up to 1,200 meters.
Omoea philippinensis is endemic to the provinces of central and western Luzon, where it grows at elevations of above 800 meters to about 2,000 meters. The plants are usually pendulous in their growth habit, and the leaves are thick and leathery. The flowers are only about 4 millimeters across, with dull green sepals and petals, with a white labellum that has purple stripes. This species is rarely seen in cultivation, and usually more appreciated amongst miniature orchid enthusiasts.
Some of the recent re-classifications have sparked numerous debates, and surely will continue to do so, as more scientific data are analyzed. In the end, it’s a personal decision, which view one might take, and perhaps changing the label on plants. It only gets much more confusing, or complicated, when plants are used for hybridization, and are being traded for horticultural purposes.