Two endangered ornamental orchid species, Bulbophyllum coweniorum and Esmeralda bella (Orchidaceae), new in the flora of Vietnam

Meanwhile, the  wide deforestation in areas of discovered species is the main fatal factor of their fast extinction in known localities.  Hence, they should be regarded as nationally critically endangered (CR) in terms of IUCN Red List categories and  criteria. The extensive commercial collecting of both species as highly demanded medicinal and ornamental plants is  additional factor of their extinction even in intact habitats.  At the same time, any present field data on both species  are very scarce for understanding of their current distribution, natural resources, ecology, biology and morphological  variation.

This is published on Turczaninowia 20(01) by Dr. Nguyen Hoang Tuan (Hanoi University of Pharmacy, vietnam) and Prof.Sci.Dr. Averyanov (Komarov Botanical Institute, Russia).

Bulbophyllum coweniorum  J.  J.  Verm.  et  P. O’Byrne

Common names. 

English: Cowen’s Bulbophyllum (named after Mr. and Mrs. Cowen, who cultivated this species and successively made it flowering in their garden in Thailand)

Vietnamese (proposed): Lọng hoa lớn

Ecology and phenology

Creeping branch and trunk epiphyte. Evergreen broad-leaved submontane forests on silicate rocks. 800–1500 m a.s.l. Flowers in March – April. Flowering in cultivation was observed in January–March, October and December (Vermeulen,  O’Byrne,  2003;  Schuiteman  et al., 2008).

Distribution

Vietnam: Dak Lak province (Chu Yang Sin Mountains) and Kon Tum province (Ngoc Linh Mountains);

Laos: Champasak province (no exact locality, Schuiteman et al., 2008).

Threat and conservation

The wide deforestation  due to uncontrolled primitive burning and shifting  agriculture, as well as forest logging throughout the  Lao PDR territory, is the leading factor of the species  extinction (Cockel, 2013). Additional threat factor  is commercial plant collecting, mainly for export  to China as ornamental and medicinal plant used  in traditional oriental medicine (Lamxay, 2009).  While this species appears rather common in the  orchid trade and in cultivation, its distribution and  occurrence in Lao PDR remains unclear (Vermeulen,  O’Byrne, 2003; Schuiteman et al., 2008; Cockel,  2013). Beside the type, two additional available  reports in Laos are based on cultivated specimens  originated  from  Champasak  province  without  indication of exact locality and data on ecology  (Schuiteman et al., 2008). Present record of this  species in Vietnam is based on the single observed,  highly depleted population standing on the verge of  full extinction due to overexploitation and habitat  loss. The absence of any current field data makes  IUCN Red List criteria not well applicable for  identification of species’ status. Data deficient (DD)  status should be formally applied for this species in  formal terms, whereas in fact it may be very near to  full extinction in the nature (nationally CR).

Bulbophyllum coweniorum on Turczaninowia20(1)

Bulbophyllum coweniorum - TuanNguyen onhup.edu.vn

Use

This and similar related species are used  in  traditional  medicine  for  treating  hemoptysis,  pneumonia,  sore  throat  and  chronic  gastritis  according  to  verbal  information  obtained  from  people  of  local  minorities.  Scientific  data  on  medicinal activity of any substances obtained from  these plants are not yet available.

Esmeralda bella Rchb. f.

Common names

English:  The  Beautiful Arachnanthe

Chinese:Kou Gai Hua Zhi Zhu Lan

Vietnamese (proposed): Bò cạp sìn hồ

Ecology and phenology

Pendulous monopodial branch and trunk epiphyte. Evergreen broad-leaved humid forests, preferably on karstic limestone. 1500–1600 m a.s.l. Flowers in November–December.

Distribution

Vietnam: provinces – Lai Chau (Sin Ho district) and Lao Cai (Sa Pa district).

India, Myanmar,  Nepal,  SW  China  (SE  Xizang,  SW Yunnan), Thailand.

Threat and conservation

Almost  total  deforestation in areas of known populations is the  main fatal factor of species extinction in Vietnam.  Habitats  harboring  few  discovered  populations  are currently degrading fast due to forest logging,  road  construction  and  agricultural  landscape  transformations. The gathering of mature samples  for local and international trade (mainly to China)  as a highly demanded ornamental plant is also  significant factor of the species extinction even  in  intact  natural  conditions. Very  strict  area  of  distribution and rapid habitat loss lead to strong  declining  of  populations  during  last  decade.  Therefore, species should be tentatively estimated  as nationally critically endangered (CR) in terms of  IUCN Red List categories and criteria (The IUCN  Red List, 2016).

Use

According to people from local minorities,  the leaves may be used in traditional medicine  for treating stomach pain and pimple. However,  scientific data on medicinal activity of any substances  obtained this species are not yet available .

Esmeralda bella onTurczaninowia 20(1)

Esmeralda bella - TuanNguyen on hup.edu.vn