Two new taxa of Curcuma sect. Ecomata (Zingiberaceae: Zingibereae), from coastal Central Vietnam

Abstract

Abstract. Nguyen DD, Le TA, Hoang QH, Le QT, Nguyen E. 2022. Two new taxa of Curcuma sect. Ecomata (Zingiberaceae: Zingibereae), from coastal Central Vietnam. Biodiversitas 23: 2512-2519. Curcuma sixsensesensis and Curcuma vinhlinhensis, two new species belonging to subgenus Ecomata from Coastal Central Vietnam, are described and illustrated in the present articles. The C. sixsensesensis easily gets confused with C. newmanii Škorni?k. in compact rhizome; short lateral inflorescence composing of a few bracts; white corolla lobes and lateral staminodes; white labellum with a yellow mid-rid band but readily distinguished in rhomboid lateral staminodes (vs. obovate) with apex acuminated (vs. rounded); labellum 3-lobed (vs. emarginated), a mid-rid band being yellow at apex half, white at the base (vs. yellow throughout); anther crest presented (vs. reduced); oblong (lightly arching) (vs. L- shaped) anther in side view with slender and inward-pointing (vs. stout and outward-facing) spurs. The second one is similar to C. pambrosima Škorni?k. & N. S. Lý in general habit and shape of the spike but differs in reduced ligule ca. 1 (vs. 4-5) mm long; lateral staminodes orange throughout (vs. yellow at apex, white at base), elliptic with round apex (vs. unequally ovate-rhomboid with acute apex); anther spurs elongate into the acute apex, outward-facing (vs. curved inward), ca. 2-3 (vs. ca. 1,5) mm long, anther crest reduced, up to 0.5 mm, 2-lobed (vs. prominent anther crest, ca. 1.5 mm apex round). Data for each described species comprises standard citation of type specimens, description, proposed species epithet etymology, data on ecology and distribution, and short taxonomic notes and morphological comparison of these new species with its allies species, a revised key to species of Curcuma sect. Ecomata in Vietnam is included.

Morphological characters, pharmacognostical parameters, and preliminary phytochemical screening of Curcuma sahuynhensis Škorni?k. & N.S.Lý in Quang Ngai Province, Vietnam

“…Le more resembles at first glance C. sahuynhensis. It is most similar to C. vinhlinhensis (Nguyen et al 2022) in the general view of habit, warm yellow to orange flowers, and the L-shaped anther but distinguished from the latter by the longer spike, the apex of the floral tube pale yellow (vs. tinged pinkish red) internally, midrib band of labellum absent lateral red lines (vs. present two lateral red lines), anther L-shaped with no the knobs below the thecae (vs. with two small blunt knobs below the thecae). It is also similar to C. cotuana.…”

“…To determine the scientific name of C. sahuynhensis, the morphological comparison method was used according to the guidelines of the Vietnamese Pharmacopoeia V (Ministry of Health 2017) and the samples were compared with the taxonomic key (Nguyen et al 2022), images, and description in the references (Sam et al 2020) to identify the species name.…”

Curcuma tuanii (Zingiberaceae) a new species of subgenus Ecomata from northern Vietnam based on morphological and molecular evidence

“…Some rhizomes were collected and grown in the garden of the Faculty of Pharmacognosy and Traditional Medicine, Hanoi University of Pharmacy to examine the stability of characteristics. The plant terminology follows Beentje (2016) and the previous work of Nguyen et al (2022). Voucher herbarium specimens are stored at VNMN and HNU herbarium.…”

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

“…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.…”