Schoenorchis, commonly known as flea orchids, is a genus of approximately 25 species of small orchids in the family Orchidaceae (order Asparagales). These plants are native to a wide arc of tropical and subtropical Asia and the Western Pacific, occurring in China, the Indian subcontinent, Indochina, Malesia, New Guinea, and island groups including Fiji, New Caledonia, Samoa, and Vanuatu, with range extensions into northern Australia.
Plants in this genus are small epiphytic, monopodial herbs — meaning they grow perched on tree bark and produce a single continuous upright stem rather than pseudobulbs. They bear thin roots and slender stems clothed in two ranks of flat to nearly cylindrical leaves whose bases sheath the stem. The flowers are small, fleshy, and often notably fragrant; they are usually white or reddish purple and do not open widely. The sepals and petals overlap at the base, giving the flower a characteristic tube-like appearance. The labellum (lip) is rigidly attached to the column, typically longer than the petals, and bears three lobes with a spur at the base; the lateral lobes are erect and the central lobe is frequently spatula-shaped.
The genus was formally described in 1825 by the Dutch botanist Carl Ludwig Blume, based on an unpublished account by Caspar Reinwardt, in Bijdragen tot de flora van Nederlandsch Indië. The type species is Schoenorchis juncifolia Reinw. ex Blume.
Some species are of conservation concern: Schoenorchis mishmensis, newly described from India, is known from fewer than 20 wild individuals and is considered critically endangered.
Etymology
The name Schoenorchis is derived from the Ancient Greek schoinos, meaning "sedge," "rush-rope," or "rope," combined with orchis, meaning "testicle" or "orchid." This naming is thought to allude to the rush-like or terete leaves characteristic of several species in the genus.
Distribution
Species of Schoenorchis are distributed across tropical and subtropical Asia and into the Western Pacific. The genus occurs in China (including Hainan, Yunnan, and Fujian), the Indian subcontinent (India, Nepal, Bhutan, Sri Lanka), Indochina (Myanmar, Thailand, Laos, Vietnam, Cambodia), Malesia (Malaysia, Indonesia, Philippines, Borneo, Sumatra, Java), New Guinea, and island groups including Fiji, New Caledonia, Samoa, and Vanuatu, with a southward extension into Queensland, northern Australia.
Ecology
Flowers of Schoenorchis are small and entomophilous, attracting insects through nectar and fragrance produced during the daytime. Pollination by bees (order Hymenoptera) has been documented in S. gemmata. Some species are not entirely dependent on insect visitors: autogamy (self-pollination) has been reported in S. paniculata and is thought to occur in S. sarcophylla as well.
Conservation
Several species in the genus are rare or poorly known. Schoenorchis mishmensis, a newly described species from India, is known from an estimated 20 individuals in the wild and is considered critically endangered.
