Sunday, February 5, 2023

[Botany • 2023] Paris siamensis (Melanthiaceae) • Revision on the Genus Paris in Thailand, with A New Species from Luang Prabang Range


  Paris siamensis Ruchis., 

in Ruchisansakun, Sraphet, Yothawut, Thamanukornsri, Suksee, ... et Triwitayakorn, 2023.
ตีนฮุ้งดอยสยาม  ||  DOI: 10.3390/plants12030430 

 Abstract
The genus Paris is an important and confusing taxon due to high variation within species, and differences between species are sometimes difficult to delimit. Thus, the status of some taxa has changed over time. To clarify the status of Paris species for plant conservation and effective management of this genus in Thailand, we performed an intensive survey in northern Thailand, studied morphological characteristics, and constructed a molecular phylogenic tree, which we compared to recently published results of this genus. Our results indicate that there are two species in Thailand: P. yunnanensis and a new species, P. siamensis. Detailed descriptions, illustrations, and the phylogenetic position of these two species are provided here.

Keywords: Paris chinensis; Melanthiaceae; threatened species; cryptic taxa; Paris polyphylla

  Paris siamensis Ruchis.
(A) Plant, (B) Leaf, (C) Flower (front view), (D) Flower (lateral view), (E) Sepal, (F) Petal, (G) Stamen, (H) Pistil (front view), (I) Pistil (lateral view).
Drawn by Jeerapach Monthanom


  Paris siamensis Ruchis.
 (A) Habit, (B) Leaf, (C) Flower (front view), (D) Flower (lateral view), (E) Sepal, (F) Petal, (G) Stamen, (H) Pistil (front view), (I) Pistil (lateral view).

 Paris siamensis Ruchis. 

Paris siamensis is similar to P. liiana but differs in having petals below sepals (versus petals above sepals), stamen number (2.2–)2.8–3 times petal number (versus stamen number 2 times petal number), and anther length 8–10 mm long (versus anther 15–40 mm long). 

Distribution. To date, endemic to Nan province, Thailand (may be found in Laos), 1050–1216 m alt.

Vernacular name. Tin Hung Doi Siam (ตีนฮุ้งดอยสยาม), 
Tin Hung Doi (ตีนฮุ้งดอย).



Distributions of the Two Paris Species in Thailand
The distributions of the plants showed that this genus is specific to high-altitude habitats. The two species in Thailand were separated by lowland areas along the Nan river. Paris siamensis was found only in Luang Prabang Range, while P. yunnanensis was more widespread and found in the Phi Pan Nam Range, the Thong Chai Range, and the Daen Lao Range, which connects to the Shan plateau where the same species is found and is connected to the populations in China.
 
 
Saroj Ruchisansakun, Supajit Sraphet, Chatchai Yothawut, Chompunooch Thamanukornsri, Nawarat Suksee, Panida Kongsawadworakul, Nattaya Srisawad, Nicha Thawara, Puangpaka Umpunjun, Supaporn Rodpradit, Winai Sangkaew and Kanokporn Triwitayakorn. 2023. Revision on the Genus Paris in Thailand, with a New Species Paris siamensis. Plants. 12(3), 430. DOI: 10.3390/plants12030430