Two new species of Curcuma subgenus Ecomata (Zingiberaceae: Zingibereae), from Central and Southwestern Thailand

PIYAPORN SAENSOUK (Diversity of Family Zingiberaceae and Vascular Plant for Its Applications Research Unit, Department of Biology, Faculty of Science, Mahasarakham University. Kantarawichai District, Maha Sarakham, 44150, Thailand)
THAWATPHONG BOONMA (Diversity of Family Zingiberaceae and Vascular Plant for Its Applications Research Unit, Walai Rukhavej Botanical Research Institute, Mahasarakham University. Kantarawichai District, Maha Sarakham, 44150, Thailand)
SARAYUT RAKARCHA (Queen Sirikit Botanic Garden, The Botanical Garden Organization. Chiang Mai 50180, Thailand)
CHARAN MAKNOI (Romklao Botanic Garden, The Botanical Garden Organization. Phitsanulok 65170, Thailand)
MATHEE WONGNAK (Queen Sirikit Botanic Garden, The Botanical Garden Organization. Chiang Mai 50180, Thailand)
SURAPON SAENSOUK (Diversity of Family Zingiberaceae and Vascular Plant for Its Applications Research Unit, Walai Rukhavej Botanical Research Institute, Mahasarakham University. Kantarawichai District, Maha Sarakham, 44150, Thailand)

Biodiversitas Journal of Biological Diversity
Vol. 23 No. 9 (2022)

Abstract. Saensouk P, Boonma T, Rakarcha S, Maknoi C, Wongnak M, Saensouk S. 2022. Two new species of Curcuma subgenus Ecomata (Zingiberaceae: Zingibereae), from Central and Southwestern Thailand. Biodiversitas 23: 4578-4588. Two new species of Curcuma L. are described. The first species, Curcuma suphanensis P. Saensouk, Boonma, Rakarcha, Maknoi, Wongnak & S. Saensouk sp. nov. was found in Suphan Buri province, Central Thailand, and the second species namely C. rosea P. Saensouk, S. Saensouk & Boonma sp. nov. was found in Uthai Thani province, Southwestern Thailand. Both species fall into the subgenus Ecomata because of the lack of conspicuous coma bract, and the presence of epigynous glands. This brings the number of species in this subgenus worldwide to 37 species. Living specimens and spirit specimens of both new species were collected from their natural habitats, morphological attributes measured, and compared to all existing species. Neither species match any previously-described species, therefore, both of them are new species to science. The first was named Curcuma suphanensis based on its province of origin (Suphan Buri Province), and the second species was named Curcuma rosea, on account of its pinkish bracts. Morphological descriptions along with their illustrations, notes on their ecology, etymology, and distributions, are presented along with a revised key to species of Curcuma subgenus Ecomata worldwide to facilitate identification.