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| Chiloschista tjiasmantoi Metusala, in Metusala, 2025. |
Abstract
Chiloschista tjiasmantoi, a new species of epiphytic leafless orchid from the northernmost region of Sumatra Island, Indonesia, is described and illustrated. The flower of this new species is morphologically close to C. javanica, but differs in having oblong-obovate petals, narrowly oblique oblong side lobes with truncate to obtuse apex, and a different shape of lip sac.
Key words: Aceh, leafless orchid, morphology, Southeast Asia
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| Chiloschista tjiasmantoi sp. nov. (A, B) and Chiloschista javanica (C, D) A inflorescence B flower, oblique view. C flower, front view D flower, oblique view. Photos by Destario Metusala. |
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| Chiloschista tjiasmantoi sp. nov. A habitus with inflorescence B flower, natural shape, front view C flower, natural shape, oblique view D dorsal sepal, flat shape E petal, flat shape F lateral sepal, flat shape G column and foot, oblique view H column and foot, front view I column and lip, side view J pollinia K stipe and viscidium L lip, above view M lip interior, back view. Line drawing by Destario Metusala from RIO 9118. |
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| Chiloschista tjiasmantoi sp. nov. Flowering plants in situ. photos by Alfajaruddin. |
Chiloschista tjiasmantoi Metusala, sp. nov.
Diagnosis: Chiloschista tjiasmantoi is morphologically similar to C. javanica, but differs in having oblong-obovate petals (vs. broadly elliptic to ovate petals), narrowly oblique oblong side lobes with truncate to obtuse apex (vs. relatively straight triangular side lobes with obtuse apex), a lip sac that has a “V” shape in longitudinal section view with a narrow angle of about 45–50° (vs. a lip sac that has an “L” shape in longitudinal section view with a wide angle of about 90°), and a very narrow cavity between the apex of the hairy callus and the thick curved front lobe of the lip (vs. a rather broad cavity).
Etymology: The specific epithet “tjiasmantoi” honors Wewin Tjiasmanto, the chairman of Tjiasmanto Conservation Fund and a philanthropist concerned with the Indonesian plant conservation.
Destario Metusala. 2025. A New Species of Genus Chiloschista (Aeridinae, Vandeae, Epidendroideae, Orchidaceae) from Sumatra Island, Indonesia. PhytoKeys. 252: 65-76. DOI: doi.org/10.3897/phytokeys.252.138190
