Two new species of Curcuma L. (Zingiberaceae) from Thailand

Abstract

Abstract. Maknoi C, Saensouk S, Saensouk P, Rakarcha S, Thammarong W. 2021. Two new species of Curcuma L. (Zingiberaceae) from Thailand. Biodiversitas 22: 3910-3921. Curcuma aruna and C. pitukii, two new species from northern Thailand, are described, illustrated, and photographed. They are endemic to Sukhothai and Lampang Provinces, northern Thailand, and the morphological characteristics of two new species are compared with their closest species, C. flaviflora, C. eburnea, and C. pierreana. Two new species, C. aruna and C. pitukii are assignable to Curcuma subgenus Ecomata. C. aruna is recognized by leaves ovate with thin chartaceous, fertile bracts 6–12, it’s glabrous on nearly all parts of the plant, flowers yellow and labellum yellow with 2 darker yellow bands in the center. C. pitukii is recognized by bracts 20–40 with purplish white to purple, corolla lobes purplish white to pale purple, staminodes white, and labellum white with an embossed yellow path along the midrib from base to apex. A detailed description, distribution, ecology, etymology, preliminary conservation status, and photographs of two new species are provided. A key to 20 species of Curcuma subgenus Ecomata in Thailand is presented.

Curcuma pulcherrima (Zingiberaceae), a new rare species of Curcuma subgen. Ecomata from eastern Thailand

“…Thailand is very rich in species diversity of Curcuma L., with more than 70 species distributed throughout the country (Sirirugsa 1966;Larsen and Larsen 2006;Sirirugsa et al 2007;Boonma and Saensouk 2019;Maknoi et al 2021;Saensouk et al 2021a, b, c;Saensouk et al 2021;Saensouk et al 2022). Therefore, this genus is proposed and classified into three sub-genera: subgenus Hitcheniopsis (Baker) K.Schum., which is distinguished by the absence of epigynous glands.…”

“…Eleven new species of Curcuma subgenus Ecomata were recently described from the Indochinese Peninsular; eleven new species are rare and endemic species from Thailand including Curcuma chantaranothaii Boonma & Saensouk, C. rangsimae Boonma & Saensouk (Saensouk et al 2021a), C. pitukii Maknoi, Saensouk, Rakarcha & Thammar, C. aruna Maknoi & Saensouk (Maknoi et al 2021), C. siamensis Saensouk & Boonma (Saensouk et al 2021d), C. achrae Saensouk & Boonma (Saensouk et al 2022a), C. lampangensis Saensouk, Maknoi & Rakarcha and C. sabhasrii Saensouk, Maknoi, Wongnak & Rakarcha (Rakarcha et al 2022), C. rosea P. Saensouk, S. Saensouk & Boonma, and C. suphanensis P. Saensouk, Boonma, Rakarcha, Maknoi, Wongnak & S. Saensouk (Saensouk et al 2022b), and C. nakhonphanomensis Boonma, Saensouk & P. Saensouk (Saensouk et al 2022c) (Nguyen et al 2022), thereby bringing the number of species in this subgenus worldwide to 41.…”

Curcuma kakchingense (Zingiberaceae), a new species from northeast India

“…The highest diversity of the genus exists in Thailand, with the latest reported 67 species (Saensouk et al 2021b). Recent explorations have resulted in discoveries of many new species from Thailand, China and Vietnam (Boonma and Saensouk 2020, Leong‐Škorničková et al 2020, 2021, Soonthornkalump et al 2020, 2021, 2022, Tanaka et al 2020, Chen et al 2021, Maknoi et al 2021, Saensouk et al 2021a,b2021b,c2021c,d2021d, 2022a,b2021b, Nguyen et al 2022, Rakarcha et al 2022). The numerous recently discovered Curcuma species serve as a good indication of existing gaps in our knowledge of the morphological variability of the genus, particularly in the underexplored Indochinese region (Leong‐Škorničková et al .…”

Curcuma nakhonphanomensis (Zingiberaceae), a new species from the lower Mekong River basin, northeastern Thailand

“…Thailand has an abundant region with subtropical and tropical climates when combined with the specific geography of the country consequently the diversity of plants. Particularly effective in the diversity of species of plants in the Zingiberaceae family, comprised of about 29 native accepted genera (Kew Science 2022), especially the genus Curcuma L. It comprised over 70 species distributed throughout the country (Sirirugsa 1966;Larsen and Larsen 2006;Sirirugsa et al 2007;Boonma and Saensouk 2019;Maknoi et al 2021;Saensouk et al 2021a, b, c, d;Saensouk et al 2022a;Rakarcha et al 2022). Thailand is considered to be the diversity center of the Curcuma subgenus Ecomata (Záveská et al 2012;Leong-Škorničková et al 2015) with the most reported species diversity throughout the country.…”