Ponerorchis

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Ponerorchis
Ponerorchis graminifolia, on Mount Gozaisho, Japan
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Orchideae
Subtribe: Orchidinae
Genus: Ponerorchis
Rchb.f.[1]
Synonyms[1]
  • Mitostigma Blume, nom. illeg.
  • Phaniasia Blume ex Miq.
  • Amitostigma Schltr.
  • Neottianthe (Rchb.) Schltr.
  • Chusua Nevski
  • Symphyosepalum Hand.-Mazz.

Ponerorchis is a genus of Asian terrestrial tuberous orchids (family Orchidaceae). It is native to temperate Eurasia, from Poland to Japan, to the north of the Indian subcontinent and to northern Indochina.[1][2]

They can be found in evergreen forests and meadows in temperate, mountainous regions. The species Ponerorchis chidorii, endemic to Japan, is also known to grow epiphytically.[citation needed]

In the horticultural trade, this genus is abbreviated as "Pnr".[citation needed] A wide range of mostly cultivars of Ponerorchis graminifolia are in cultivation, but are rarely grown outside Japan.[3]

Description[edit]

Ponerorchis species grow from an ovoid tuber. They are slender plants with one to three usually slightly fleshy leaves. The flowers are all borne on the same side of the stem. The upper sepal and the two lateral petals form a hood. The column is short and has obvious side appendages. There is a rostellum separating the pollinia from the stigma.[4]

The genus was substantially expanded in 2014, so older descriptions do not necessarily apply to the revised genus. Ponerorchis was said to be differentiated from Amitostigma and Neottianthe by the presence of a bursicle or "sac" around the viscidium (a sticky pad at the base of the pollinium). However, this feature was found to be present in some species formerly assigned to Amitostigma and to be difficult to detect in some species of Ponerorchis. In the expanded genus, a bursicle is present is some species and not in others.[4]

Taxonomy[edit]

Phylogeny and classification[edit]

The genus Ponerorchis was erected by Heinrich Gustav Reichenbach in 1852 for the species Ponerorchis graminifolia. Phylogenetic studies between 1997 and 2003 showed that Ponerorchis, when broadly defined, formed a clade with the genera Amitostigma, Neottianthe and Hemipilia. Ponerorchis, as then circumscribed, was not monophyletic. In 2003, in advance of further studies involving more species, Ponerorchis was broadened to include Chusua, and an "orphan" species was transferred from Ponerorchis to become Hemipilia brevicalcarata.[5] A more detailed molecular phylogenetic study in 2014 confirmed the strong relationship between Amitostigma, Neottianthe and Ponerorchis, whose species were mixed together in a single clade, making none of the three genera monophyletic as then circumscribed. Amitostigma and Neottianthe were subsumed into Ponerorchis,[4] making it a considerably larger genus.

Ponerorchis was previously distinguished from related genera by the presence of bursicles (pouchlike receptacles) enclosing the pollinia. The presence or absence of a bursicle was found not to be a useful diagnostic character, having arisen independently at least four times in the Orchideae.[4]

Ponerorchis is placed in the orchid subfamily Orchidoideae, tribe Orchideae, subtribe Orchidineae. After the genera were re-circumscribed as explained above, the relationship between Ponerorchis and the rest of the subtribe is as shown in the cladogram below.[4]

Orchidinae

all other genera

Species[edit]

Species accepted as of March 2018:[6]

Distribution[edit]

Ponerorchis species are widely distributed in Eurasia, mainly in temperate regions, but extending into northern Indo-China. In Europe, they are found in Poland and Eastern Europe. In temperate Asia, they extend from Siberia to the Russian Far East, Mongolia, China and Eastern Asia. They are also found in the north of the Indian subcontinent (the western Himalayas, Nepal, the eastern Himalayas and the Assam region) and in northern Indochina (Myanmar, Thailand and Vietnam).[1]

References[edit]

  1. ^ a b c d "Ponerorchis". World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew. Retrieved 2018-03-22.
  2. ^ Flora of China v 25 p 92, 小红门兰属 xiao hong men lan shu, Ponerorchis
  3. ^ Stewart, Joyce (1994). "Ponerorchis: alpine orchid gems from Japan". The New Plantsman. 1 (1): 29–35.
  4. ^ a b c d e Jin, Wei-Tao; Jin, Xiao-Hua; Schuiteman, André; Li, De-Zhu; Xiang, Xiao-Guo; Huang, Wei-Chang; Li, Jian-Wu & Huang, Lu-Qi (2014). "Molecular systematics of subtribe Orchidinae and Asian taxa of Habenariinae (Orchideae, Orchidaceae) based on plastid matK, rbcL and nuclear ITS". Molecular Phylogenetics and Evolution. 77: 41–53. doi:10.1016/j.ympev.2014.04.004. PMID 24747003.
  5. ^ Bateman, Richard M.; Hollingsworth, Peter M.; Preston, Jillian; Luo, Yi-Bo; Pridgeon, Alec M. & Chase, Mark W. (2003). "Molecular phylogenetics and evolution of Orchidinae and selected Habenariinae (Orchidaceae)". Botanical Journal of the Linnean Society. 142 (1): 1–40. doi:10.1046/j.1095-8339.2003.00157.x.
  6. ^ "Search for Ponerorchis". World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew. Retrieved 2018-03-22.

External links[edit]