A new species and a new record of Curcuma subgen. Curcuma (Zingiberaceae) from Northern Thailand

Saensouk S, Boonma T, Saensouk P. 2021. A new species and a new record of Curcuma subgen. Curcuma (Zingiberaceae) from Northern Thailand. Biodiversitas 22: 3617-3626. Recent fieldwork to study the species diversity of the Zingiberaceae family in Thailand and preparing a revision of the Curcuma genus for the Flora of Thailand, an undescribed species of Curcuma uses as traditional medicinal for more than two decades well known in the Thai vernacular name “Rang-Jued” was found, this vernacular name is also used to call the other two medicinal plants belonging to different families which are Thunbergia laurifolia Lindl. (Acanthaceae), and Crotalaria spectabilis Roth (Fabaceae), thus some villagers are named Curcuma rangjued as “Rang-Jued-Khamin” to communicate specifically identify species in order to use correct species for each utilization. While Thunbergia laurifolia was called "Rang-Jued-Thao", which "Thao" means "vine" refers to its habit and Crotalaria spectabilis was called "Rang-Jued-Ton" which "Ton" means "stem" refers to its erect stems. After comparing this undescribed species of Curcuma with its allies species, we found that this species did not match with any existing taxa, thus described with detailed illustrations, photographs, summaries for its distribution, ecology in the name of Curcuma rangjued Saensouk & Boonma and followed by a new record of C. cordata Wall. for Thailand which in the past has been determined as a synonym of C. petiolata Roxb. but now it is back to a recognized name once again. Both species in this study were found distributed in the northern region of Thailand and belong to Curcuma subgenus Curcuma, their description along with ecology, phenology, and a revised key to 28 species of Curcuma subgenus Curcuma in Thailand are also present for facilitating identification.

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.

New species and new records for the climber genus Friesodielsia (Annonaceae) in the flora of Thailand

Six new species of Friesodielsia (Annonaceae) are described and illustrated, seven species are documented for Thailand for the first time, and Oxymitra fornicata (Roxb.) D. Das var. glabra is raised to species rank as Friesodielsia andamanica. These additions bring the species diversity of Friesodielsia in Thailand to 16 species. A key to the Thai species is provided.

Additions to Annonaceae in the Flora of Thailand

Work toward completion of the Annonaceae treatment for the Flora of Thailand revealed 18 species previously unrecorded for the country, six of them in the genus Fissistigma. In addition, several species previously placed in synonymy are re-instated, for which we propose three new combinations in the genera Mitrella, Monoon, and Sphaerocoryne.

New combinations in Debia, Dimetia and Scleromitrion (Rubiaceae) relating to the Flora of Thailand

New combinations for five taxa in the Hedyotis-Oldenlandia complex (Rubiaceae) in Thailand are proposed, namely Debia rosettifolia, Dimetia capitellata var. pubescens, D. prainiana, D. ridleyana and Scleromitrion kerrii. Six relevant taxa are lectotypified.

New species and new records of Artabotrys (Annonaceae) from peninsular Thailand

Two new species of Artabotrys (Annonaceae) are described from peninsular Thailand. Artabotrys longipetalus J.Chen & Eiadthong, sp. nov., is unique among Artabotrys species in Thailand in having linear petals, relatively long flower pedicels and sessile monocarps. Artabotrys insurae J.Chen & Eiadthong, sp. nov., resembles Artabotrys uniflorus (Griff.) Craib, but can be distinguished by its oblique leaf base, flat petal blades, apiculate anther connective apex and the presence of a monocarp stipe. In addition, two new records for the Flora of Thailand are reported, viz. Artabotrys crassifolius Hook.f. & Thomson and Artabotrys pleurocarpus Maingay ex Hook.f. & Thomson; both species are so far only known from peninsular Thailand. A key to the 20 species of Artabotrys in Thailand is provided.

Taxonomic Notes on the ‘Mahat’ (Artocarpus lacucha and A. thailandicus, Moraceae) Species Complex in Thailand

‘Mahat’ is a well-known medicinal plant utilized in Thailand. The Thai name ‘Mahat’ has been used in many scientific articles for years. However, it is, unpredictably, a homonym of two scientific names in Flora of Thailand, i.e., A. lacucha and A. thailandicus. Additionally, both species are complex due to their high morphological variation. This causes difficulties in species identification especially when this Thai name is referred to as the scientific name for research publication, quality control of pharmaceutical raw materials, and registration of pharmaceutical products. In this study, we scrutinized the taxonomy of ‘Mahat’ by detailed examination of its morphology and distribution, including molecular and qualitative phytochemical studies. Leaf surfaces were inspected using scanning electron microscopy. The phylogeny of both species was studied using DNA sequences of nuclear and plastid regions. Chromatographic fingerprints, focusing on the major active compound oxyresveratrol, were identified using high-performance liquid chromatography. According to our current study, phylogenetic evidence showed that some samples of both species were clustered together in the same clade and phytochemical fingerprints were almost identical. These results are valuable data for taxonomic revision in the near future and reveal the possible utilization of A. thailandicus as a new material source of oxyresveratrol in the pharmaceutical industry.