Cephalantheropsis is a small genus of about five species of terrestrial (rarely epiphytic) orchids in the family Orchidaceae, order Asparagales.
Described by Andre Guillaumin in 1960 and published in the Bulletin du Museum National dHistoire Naturelle, the genus is closely related to Calanthe — so closely that the GBIF backbone taxonomic treatment considers it a synonym of Calanthe, while other taxonomic authorities including the Flora of China maintain it as a distinct accepted genus.
These are reed-stemmed herbs with creeping rhizomes, erect many-noded cylindrical stems sheathed toward the base, and numerous plicate (pleated) leaves with clasping bases. Inflorescences emerge laterally from the lower stem nodes, bearing racemes of small to medium-sized flowers that spread horizontally or nod. The sepals and petals are similar and free, spreading to reflexed. The lip is three-lobed, spurless, but with a shallowly saccate base; lateral lobes loosely embrace the column, and the mid-lobe has a strongly crisped (ruffled) margin. The column is stout and winged, lacking a column foot. Each flower bears eight waxy pollinia in two groups of four.
The genus ranges from northeastern India through southern China to the Ryukyu Islands of Japan, mainland Southeast Asia, the Philippines, and Sumatra. Three of the five species occur in China. The type species, Cephalantheropsis obcordata, is a robust plant reaching 35–100 cm tall with green or yellowish-green flowers that open widely.
Etymology
The genus name Cephalantheropsis is constructed from Cephalanthera (a genus of orchids in the same family) and the Greek suffix -opsis, meaning "resembling" or "having the appearance of," referring to the morphological similarity between the two genera.
The Chinese name (huang lan shu) means "yellow orchid genus." The genus was described by French botanist Andre Guillaumin in 1960.
Distribution
Cephalantheropsis is native to tropical and subtropical Asia, ranging from northeastern India through southern China to the Ryukyu Islands of southern Japan, and extending into mainland Southeast Asia, the Philippines, and Sumatra.
Of the approximately five species in the genus, three are found in China.
Taxonomy & Classification
The taxonomic status of Cephalantheropsis is contested. The GBIF backbone taxonomy treats it as a synonym of Calanthe R.Br., while other GBIF constituent datasets and the Flora of China accept it as a distinct genus in tribe Collabieae.
The genus was described by Guillaumin in 1960 in the Bulletin du Museum National dHistoire Naturelle (ser. 2, 32: 188). Its species were previously classified under Calanthe and Phaius before being segregated based on morphological differences, including the spurless lip, eight pollinia in two groups of four, and the lack of a column foot.
