A revision of Beilschmiedia (Lauraceae) for Thailand and Indochina

A revision of the genus Beilschmiedia (Lauraceae) from Thailand and Indochina is presented with a summary of its taxonomic history, plus keys, full descriptions of each species, distribution maps, conservation assessments, ecological information, ethno-botanical notes and a discussion of its morphology. In this treatment, 21 species are recognized; 14 names are lectotypified (B. argentata, B. balansae, B. balansae var. muticarpa, B. clarkei, B. elegantissima, B. ferruginea, B. globularia, B. glomerata var. tonkinensis, B. lucidula, B. obovalifoliosa, B. palembanica, B. poilanei, B. sphaerocarpa and B. wightii), five names are placed into synonymy for the first time, and B. laotica Kosterm. ex de Kok is validly published here for the first time. In addition, one new variety (B. percoriacea var. percoriacea de Kok) is proposed and one new combination (B. percoriacea var. glaucoides de Kok) is made. Nine species are considered to be Least Concern, one is Critically Endangered, five are Endangered, and five are listed as Vulnerable.

The genus Gaertnera (Rubiaceae) in Thailand

Two species of Gaertnera in Thailand, viz. G. junghuhniana and G. sralensis, are enumerated and described. A lectotype is designated for G. taiensis, a synonym of G. junghuhniana. A key to species and data on distribution, habit and phenology are also provided.

Uvaria clementis (Annonaceae), a new record for Thailand

A new species record for Thailand, Uvaria clemantis is discovered from Khao Luk Lom Mountain, Rattaphum District, Songkhla Province. A description and photographs are provided.

Schefflera (Araliaceae) in Thailand becomes Heptapleurum

Following recent studies showing that Asian Schefflera should be treated under the separate genus Heptapleurum, the names for the Thai species belonging to this genus are listed. Two new combinations are proposed for S. bengalensis and S. poomae. For two species of Schefflera recognized, S. pueckleri and S. simulans, different epithets must be used under Heptapleurum, namely H. calyptratum and H. affine.

Impatiens tanintharyiensis, a new record of Impatiens sect. Semeiocardium (Balsaminaceae) for Thailand

Impatiens tanintharyiensis (Balsaminaceae) is reported in Thailand for the first time from a population in Ngao Waterfall National Park, Ranong Province. This population differs from that at the type locality in Myanmar by having smaller, purple flowers (vs bigger purplish-pink flowers). An expanded description of this taxon and colour photographs are provided.

Two new species and 18 new records for the flora of Laos

Six pteridophyte species of five families and 12 spermatophyte species of 10 families are reported from Bolaven Plateau, southern Laos, as new records to the flora of Laos. Moreover, two new species, Sterculia bolavenensis (Malvaceae) and Wikstroemia bolavenensis (Thymelaeaceae), are described. For each species, voucher specimens are cited, photographs are shown and additional information including geographical distribution, ecology and taxonomic notes are provided.

Notes on the genus Ardisia (Primulaceae) in Thailand and Peninsular Malaysia

The lectotype for Ardisia kerrii is designated here. Ardisia cordulata var. appresso-hirsuta is placed as a new synonym of A. demissa. Additionally, the correct locations of four species that were misinterpreted are also given. Now A. betongensis is excluded from the list of Thai Ardisia.

Antheroporum puudjaae (Millettieae: Fabaceae), a new species from Thailand

Antheroporum puudjaae, a new species discovered in Northern Thailand, is described and illustrated. It differs from other described species of Antheroporum by its drooping inflorescences and oblong fruits with 2–4 seeds. The generic description is expanded based on these new characters. An emended key to the species for the Flora of Thailand is also provided.

Thunbergia amphaii (Acanthaceae) a new species from Thailand

Thunbergia amphaii, a new species from North-Eastern Thailand is described and illustrated. The pseudo-umbel inflorescence is diagnostic for this species. The pollen morphology, especially the size and the pericolpate aperture arrangement, further support this species as new to science.

Taxonomic notes on the Rutaceae of Thailand

Nomenclatural problems with the name Atalantia simplicifolia are discussed, and it is shown that A. roxburghiana, often used for it, is illegitimate. Formerly part of Murraya, Bergera is recognized as separate genus for Thailand. Murraya siamensis is reduced to a synonym of Bergera koenigii.