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| Thismia aliasii Siti-Munirah, in Siti-Munirah et Alias, 2025. |
Abstract
A new mycoheterotrophic species, Thismia aliasii, is described and illustrated. This species inhabits a hill dipterocarp forest in mountains of eastern Peninsular Malaysia. Thismia aliasii differs from other Thismia species by the following features: tepals equal in size and shape with different length of their appendages, appendages of the outer tepals shorter than those of the inner tepals (3.5 mm vs. ca. 26–32 mm long), stamen supraconnective at apex with three long filiform appendages and two acute appendages, and the margins of individual connectives abaxially raised into a conspicuous rib. With respect to floral morphology, T. aliasii should be placed to Thismia subsect. Odoardoa. According to the categories and criteria of the IUCN Red List, T. aliasii is provisionally classified as Critically Endangered (CR).
Key words: Achlorophyllous plants, endemism, Gunung Chemerong, Monocots, Terengganu, Thismia subsection Odoardoa
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| Thismia aliasii A flowering plant (over-brightened by a camera flash) B anthetic flower, top view B1 annulus, top view B2 tip of appendage of outer tepal B3 tip of appendage of inner tepal C distal portion of flower, lateral view C1 flower, top view D floral tube (with its apex removed), side view D1 outer surface of floral tube (showing tiny glands) E inner surface of flower tube, pistil and ovary E1 longitudinal section of ovary and pistil with stigma F fruiting plant F1 seeds in capsule F2 seeds. Photos by Siti-Munirah (A, C1: FRI 79119; A1, B–E: FRI 79167; E1, F1, F2: FRI 91119, spirit material) and Mohamad Alias (F: FRI 91119). |
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| Thismia aliasii A plant with flower and roots B top view of flower showing tepals and annulus C bract (abaxial view) D leaf (abaxial view) E style and stigma F stamens (outer view) G stamens (inner view) H fruiting plant. All drawn by Mohamad Aidil Noordin from spirit material, FRI 91119. |
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| Habitat and habit of Thismia aliasii A plants in situ B plant with flower bud C plant with anthetic flower. All photos by Siti-Munirah. |
Thismia aliasii Siti-Munirah, sp. nov.
Diagnosis. Thismia aliasii is very similar to the species of the T. subsection Odoardoa, as the tepals are the same in shape and size. However, the tepal appendages of the new species are of unequal length, the inner ones are longer than the outer ones, while the tepal appendages of the other species are of equal length. In addition, in the new species the margins of the individual connectives are raised abaxially into the conspicuous rib, whereas connectives are almost flat abaxially in the rest of the species.
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| Landscapes of Gn. Chemerong and the species of Thismia found there A the Chemerong waterfall with a height of 370 m B the Chemerong River not far from the habitat of T. aliasii C Thismia aliasii, an individual discovered by Mohamad Alias in 2019 (FRI 91119) D Thismia aseroe (FRI 79116) found on the trail at Hutan Lipur Chemerong. Photos by Siti-Munirah (A, B, D) and Mohamad Alias (C). |
Etymology: The species is named after Mr. Alias (the second author), a current ranger of the Terengganu Forestry Department (JPNT), who is also a freelance photographer (known as John Sp) and who was the first to discover the species.
Mat Yunoh Siti-Munirah and Shakri Mohamad Alias. 2025. Thismia aliasii (Thismiaceae), A New Species from Terengganu, Peninsular Malaysia. PhytoKeys. 254: 175-188. DOI: doi.org/10.3897/phytokeys.254.136085
