Research Article
Research Article
Thismia kenyirensis (Thismiaceae), a new species from Taman Negeri Kenyir, Terengganu, Peninsular Malaysia
expand article infoMat Yunoh Siti-Munirah, Nikong Dome§
‡ Forest Research Institute Malaysia, Kepong, Malaysia
§ DigitalDome Photography, Terengganu, Malaysia
Open Access


A new mycoheterotrophic species, Thismia kenyirensis Siti-Munirah & Dome from Peninsular Malaysia, is described and illustrated. Thismia kenyirensis differs from other previously described species in the following characteristics: the flower tube is completely orange, with alternating darker and paler-coloured longitudinal lines on the outer and inner surfaces, the outer tepals are ovate (petaloid), the inner tepals are narrowly lanceolate, each ending with a long appendage. According to the IUCN Red List categories and criteria, T. kenyirensis is provisionally classified as Least Concern.


Brunonithismia, lowland dipterocarp forest, rare species


Thismia Griff. is a genus of non-photosynthetic flowering plants belonging to the family Thismiaceae. Thismia species are small herbs, with scale-like leaves and actinomorphic or zygomorphic, urceolate to campanulate flowers. Thismia includes about 100 species worldwide (from Imhof 2010 onwards, Siti-Munirah et al. 2022) and it is the most widespread and species-rich genus in the family Thismiaceae with high endemism. Their range extends from tropical and subtropical Asia to northern and eastern Australia and New Zealand and from tropical South America to Costa Rica, with isolated occurrence in North America (POWO 2022). Many species are believed to be extremely rare and have a scattered range. They are easily overlooked in the wild due to their small size and the short-lived nature of their aboveground parts (Larsen and Averyanov 2007). In Malaysia, Terengganu is currently the state with the most Thismia records, with 11 reported species: T. alba Holttum ex Jonker, T. arachnites Ridl, T. aseroe Becc, T. brunneomitroides Suetsugu & Tsukaya, T. domei Siti-Munirah, T. clavigeroides Chantanaorr. & Seelanan, T. javanica J.J.Sm., T. latiffiana Siti-Munirah & Dome, T. ornata Dančák, Hroneš & Sochor, T. sitimeriamiae Siti-Munirah, Dome & Thorogood, T. terengganuensis Siti-Munirah (Siti-Munirah and Dome 2019, 2022a, b; Siti-Munirah et al. 2021).

Currently, five of the species reported in Terengganu are known from the Kenyir State Park (Taman Negeri Kenyir, TNK) (Siti-Munirah and Dome 2022b). The TNK is located in the eastern part of Peninsular Malaysia in the state of Terengganu (Map 1). It used to be part of the Tembat Forest Reserve (FR), but in 2018 and 2019, parts of Tembat FR were designated as TNK. The forest area includes part of the forest around Tasik Kenyir (Kenyir Lake), which is adjacent to Terengganu National Park (Taman Negara Terengganu) and also connected to Tembat FR forest and Kelantan State (Map 2). During the scientific expedition to the TNK on 8 September 2020, the second author and his team visited the Sungai Cendana area in the southern part of the TNK and discovered a population of an unknown Thismia plant, which he forwarded to the first author. Together, we revisited the populations in June 2022. After further investigation and comparison with known species of Thismia, we concluded that this plant is distinct from previously described species of the genus. We therefore report and describe it here as a new species for science.

Map 1. 

Taman Negeri Kenyir, Terengganu (black circle), the type locality of Thismia kenyirensis.

Map 2. 

Map of Tasik Kenyir and the forest boundaries. (Map sourced from NBS).

Materials and methods

Our assessment is based on material collected in Taman Negeri Kenyir, Hulu Terengganu, Terengganu (Map 1). The specimens were preserved in 70% ethanol. All the specimens have been deposited in Kepong Herbarium (KEP) and have been examined for taxonomic treatment. Morphological characters and measurements were examined using an Olympus SZ61 stereo microscope and high-resolution macrophotography. Additionally, measurements were taken from spirit material. The specimen features were compared in detail with the original drawings and descriptions of morphologically similar species of Thismia provided by Jonker (1938), Larsen and Averyanov (2007), Mar and Saunders (2015), Chantanaorrapint (2018), Tanaka et al. (2018), Suetsugu et al. (2018), Siti-Munirah and Dome (2019) and Nuraliev et al. (2020).

Taxonomic account

Thismia kenyirensis Siti-Munirah & Dome, sp. nov.

Figs 1, 2, 3


Distantly similar to Thismia hongkongensis Mar & Saunders but differs by petaloid, ovate outer tepals which are ca. 8 mm long, narrowly lanceolate-linear, ca. 8 mm long inner tepals which are not forming a lose-dome, up to 28 mm long appendages of inner tepals, orange floral tube, which lacks reticulate pattern on its inner surface and connective apex with 3 long appendages.

Figure 1. 

Thismia kenyirensis A plant with flower and roots B top view of flower showing tepals C top view of ovary and stigma D stamen (i, side view; ii, inner view) E outer view of three pendulous stamens F longitudinal section of ovary G style and stigma H bract I leaf. All from FRI91122a (spirit material). Drawings by Mohamad Aidil Noordin.


Malaysia. Peninsular Malaysia: Terengganu, Hulu Terengganu District, Taman Negeri Kenyir, Sungai Cendana, elev. ca 204 m, 8 Sept 2020, Dome Nikong, FRI 91122a (holotype KEP!, spirit collection, barcode no. SC12015).

Figure 2. 

Thismia kenyirensis A mature plant with flowers and roots, scale in centimetres (cm) (FRI91122b) B mature plant in natural habitat (FRI91122a) C vermiform roots (FRI91122c) D young flower with mature ovary and stigma (FRI91122c). Photos by Siti-Munirah MY (A); Dome Nikong (B–D).


Achlorophyllous herb, up to 130 mm tall. Roots vermiform, unbranched, ca. 1 mm in diameter, light brown. Stem erect, up to 90 mm long, 1.5–2 mm in diameter, pale brownish-orange, bearing 1–2 flowers. Leaves 2–4, spirally arranged, triangular to narrowly triangular, scale-like, acute, margin almost entire but slightly irregularly serrate, 2–6 mm long, ca. 1 mm wide at base, pale brown. Involucral bracts 3, similar to leaves but slightly larger, spirally arranged, triangular to narrowly triangular, scale-like, acute, entire, 8 mm long, ca. 1.5–2.5 mm wide at base, pale brown or pale orange. Pedicel up to 6 mm long at anthesis, elongating to ca. 10 mm long after anthesis, pale brown. Flowers terminal, actinomorphic, ca. 52 mm long (including ovary, floral tube and inner tepal with appendage); floral tube urceolate, 12–15 mm long, ca. 5 mm wide at base, ca. 6 mm wide at middle, ca. 7 mm wide distally; outer surface glabrous, orange to brownish-orange, with 12 darker orange longitudinal ribs alternating with 12 paler longitudinal lines, inner surface smooth or rough, almost similar to outer surface, without transverse bars or reticulate ornamentation; outer tepals 3, free, petaloid, ovate, apex acute, 8 mm long, ca. 4–5.5 mm wide (ca. 4 mm at base, ca. 5.5 mm above middle), glabrous, bright orange; inner tepals 3, free, narrowly lanceolate-linear, 8 mm long, ca. 1 mm wide, glabrous, dark orange, apically bearing a tentacle-like appendage; appendage narrowing towards apex, ca. 27–28 mm long, 0.5 mm wide, dark orange at base and bright orange at apex; annulus dark orange, glabrous. Stamens 6, pendent from the annulus, outer side greenish-orange or greenish-brown, inner side dark-brown to blackish and paler, filaments free, ca. 1 mm long, curved downwards; connectives flattened at inner surface, laterally connate to form a tube, ca. 4–5 mm long, narrow at base (ca. 0.8 mm wide) and broad at apex (ca. 1.7 mm wide), connective apex with 3 appendages, slightly curved inside, each appendage ca. 1.5 mm long; outer side of connective bearing a skirt-like lateral appendage protruding towards floral tube; lateral appendage not exceeding the tip of the connective appendages, with short translucent trichomes on margin, interstaminal glands greenish translucent, inserted on the line of fusion between connectives at the level of attachment of lateral appendages. Ovary inferior, unilocular; placentas 3, free, forming columns and arising from the bottom of the ovary; ovules numerous. Style dark brown-orangish, ca. 1 mm long; stigma ca. 1 mm long, papillose, 3-lobed, with lobes ± rectangular, bifurcate at apex, pale brown or orangish to whitish. Fruit cup-shaped, 3–5 mm in height, 4–6 in diameter, pale orange (or white to creamy orange), darker at upper part. Seeds unknown.

Figure 3. 

Thismia kenyirensis A bracts with ovary and pistil, lateral view B top view of stigma C flower, side view D longitudinal section of floral tube and stamens E flower, top view F annulus G stamens, outer view. Photos by Siti-Munirah MY (A–C, E, F; All from FRI 91122b); Dome Nikong (D, G; No specimens).

Additional specimen examined (paratype)

Malaysia. Peninsular Malaysia: Terengganu, Hulu Terengganu District, Taman Negeri Kenyir, Sungai Cendana, elev. ca 204 m, 8 Sept 2020, Dome Nikong, FRI 91122b (KEP, spirit collection, barcode no. SC12016), FRI 91122c (KEP, spirit collection, barcode no. SC12017); Taman Negeri Kenyir, Sungai Cendana, elev. ca. 156 m, 16 June 2022, Siti-Munirah MY, FRI98678 (KEP, spirit collection, barcode no. SC12018).


Endemic to Terengganu, Peninsular Malaysia. Currently, the occurrence is only from the type locality, Sungai Cendana area (Map 1). In addition, T. kenyirensis was observed in two other populations in the vicinity of Tasik Kenyir. It was sighted near Sungai Saok and on the way to Gunung Gagau (Wong Pui May personal communication), both in the Tasik Kenyir region. However, there are still no specimens and GPS information to verify these findings. This means that only the occurrence of the population in Sungai Cendana has been confirmed.


In moist shady areas of lowland dipterocarp forest on moist soil at elevations of 150–220 m a.s.l. Flowering and fruiting mostly from September to April, but also recorded to flower in June. Historically, the type locality was botanized as early as 2007. Based on the results of Lim et al. (2008), T. alba was also recorded during the survey in the Sungai Cendana area. This is in contrast to T. kenyirensis, which was not mentioned, implying that it was not seen or collected at that time. During our recent visit, we were also able to find T. alba not far from the original population of T. kenyirensis.


The epithet refers to Lake Kenyir, Kenyir State Park (Taman Negeri Kenyir), where the species was found.

Conservation status

According to the IUCN standards (IUCN 2022), we propose to classify the preliminary conservation status of the species as Least Concern (LC). This is because the species is likely to be widespread in TNK, where it has been sighted a few times at the type locality (Sungai Cendana) and also by other observers at two other sites, and its entire habitat is in a fully protected forest area. In addition, nearby forests in Terengganu National Park (Taman Negara Terengganu) are also fully protected. As mentioned earlier, it is very likely that there are other populations in the vicinity of Tasik Kenyir. According to the second author’s observations, four individuals were sighted near Sungai Saok and one on the way to Gunung Gagau on 22 November 2022. However, no specimens are available for confirmation. Thismia kenyirensis occurs in intact habitats in forested areas in TNK. However, the species is very common only during the flowering season and its populations are mostly scattered, as few individuals or solitary individuals were observed during the flowering season. During the first check of the type locality, the population in Sungai Cendana in 2020, about 20 adult individuals were found. However, during a revisit in 2022, only a single individual was observed.


Thismia kenyirensis is easily recognised by the following combination of characteristics: vermiform roots, almost uniform light-to-dark orange flower coloration, petaloid ovate outer tepals, narrowly lanceolate-linear inner tepals with long appendages and each stamen with 3 appendages at its apex. Within the infrageneric classification by Kumar et al. (2017), T. kenyirensis resembles species of Thismia subgenus Thismia section Thismia subsection Brunonithismia Jonker, especially by its free and unequal tepals. Eight species are placed in subsection Brunonithismia by Kumar et al. (2017): T. arachnites, T. brunonis Griff, T. gardneriana Hook.f. ex Thwaites, T. hongkongensis, T. javanica, T. labiata J.J.Sm., T. neptunis Becc. (proved to be only distantly related to the other species of the subsection by Shepeleva et al. 2020) and T. tentaculata K.Larsen & Aver. Of them, T. arachnites and T. javanica occur in Peninsular Malaysia, including the state of Terengganu. They both are readily distinguished from T. kenyirensis (Fig. 4, Table 1). In addition, T. breviappendiculata Nob. Tanaka (Tanaka et al. 2018) from Myanmar, T. bokorensis Suetsugu & Tsukaya (Suetsugu et al. 2018) from Cambodia, T. gardneriana from Sri Lanka and T. tentaculata from Hong Kong and Vietnam are similar to T. kenyirensis. In a molecular phylogenetic reconstruction provided by Shepeleva et al. (2020), T. javanica, T. hongkongensis, T. gardneriana and T. tentaculata occupied a relatively isolated and unstable position. All these species (and also T. kenyirensis) are characterised by free appendaged inner tepals and outer tepals without appendages. A more detailed phylogenetic analysis is required to test the monophyly of this morphological group, and the relationships of each of these species including T. kenyirensis.

Figure 4. 

Morphologically close species to T. kenyirensis in Peninsular Malaysia A–C T. arachnites (Taman Negeri Kenyir) D–F T. javanica (Telemong Forest Reserve). Photos by Dome Nikong (A–C, F) and Siti-Munirah MY (D, E, G).

Table 1.

Morphological comparison of T. kenyirensis with similar species T. arachnites (Chantanaorrapint 2018), T. bokorensis (Suetsugu et al. 2018), T. breviappendiculata (Tanaka et al. 2018), T. brunonis (Jonker 1938), T. gardneriana (Jonker 1938; Bandara et al. 2020), T. hongkongensis (Mar et al. 2015), T. javanica (Siti-Munirah and Dome 2019; Nuraliev et al. 2020) and T. tentaculata (Larsen and Averyanov 2007; Nuraliev et al. 2020).

Characters T. kenyirensis T. arachnites T. bokorensis T. breviappendiculata T. brunonis T. gardneriana T. hongkongensis T. javanica T. tentaculata
Colour of floral tube Orange to brownish-orange with 12 darker orange longitudinal ribs White to orange with 6 or 12 reddish vertical streaks in the upper part Pure white White, with 12 translucent longitudinal ridges Yellowish Yellowish-orange Pinkish-white with 12 dark red vertical ribs White to pale orange or light orangish-red Pure white, sometimes with antetepalous veins indistinctly tinged with red
Presence of transverse bars/ ornamentation on inner side of the floral tube Absent/absent Present/absent Absent/absent Present/absent Present/absent Absent/ Not known Absent/present Present/absent Absent/present
Outer tepal Shape Ovate, petaloid Broadly ovate Broadly triangular, apex broadly obtuse or rounded Ovate, obtuse Broadly ovate, obtuse Broad, rotundate Triangular Ovate-triangular Isosceles triangular, broadly obtuse or rounded
Length (mm) 8 5–6.5 1.2 2 Not known 1.5 1.8 1–3.5 1.8–2.4
Colour Bright orange Yellow to orange. Light yellow Yellow Not known Yellow Dark red Orange to red or yellow, translucent Light yellow or tinged with red, translucent
Inner tepal (without appendage) Shape Narrowly lanceolate-linear Triangular Narrowly triangular Isosceles triangular Triangular at the base, caudate in long, thick, filiform tails Subulate Spatulate, adaxially concave Narrowly triangular Triangular with broad base
Length (mm) 8 6.5–9 2.6 2 Not known Not known 3.3 1.5–3.3
Colour Bright orange Orange to reddish-orange at the base Light yellow Yellow Not known Yellowish-orange Dark red Orange to red or yellow and usually dark red towards apex Light yellow
Stamen Apex 3 long, slightly curved appendages 3-toothed, each tooth bearing a distinct stiff hair 3-toothed, each tooth narrowly triangular, with ca. 1 mm long Lobed With numerous teeth 2-toothed, each tapering into a stiff hair 2-toothed, adorned with trichomes 3-toothed, each tooth bearing hair 2-toothed, each tooth tapering into hair, sometimes with additional hairs between teeth


This research was conducted under the Flora of Peninsular Malaysia Project (FPM) at the Forest Research Institute Malaysia (FRIM), Kepong, funded by the Ministry of Natural Resources, Environment and Climate Change (NRECC), formerly the Ministry of Energy and Natural Resources (KeTSA), under the 11th and 12th Malaysian Plans (SPPII No. P23085100018003) and the Nagao Research Grant to partially fund Thismia research. We thank the Majlis Pengurusan Taman Negeri Terengganu, Jabatan Perhutanan Negeri Terengganu (JPNT), Pusat Sains & Kreativiti Terengganu, Universiti Malaysia Terengganu (UMT), Sri Rao V of NBS (Nature Based Solutions Sdn. Bhd.). We thank Ey-ang, Ey-keb (Orang Asli Bateq) & KBG team for their assistance in the field study. Special thanks to Wong Pui May of Project Takob for her kind help in many ways. We would like to thank Michal Hroneš, Martin Dančák, Maxim Nuraliev, and Sahut Chantanaorrapint for constructive comments on our manuscript. Mohamad Aidil Noordin is thanked for botanical drawings, Wendy SY Yong for assistance in conservation status assessment, and Mohd Faizal MT for encouragement and great help in preparing the manuscript.


  • Bandara C, Priyankara T, Atthanagoda AG, Lakkana T, Ediriweera S, Kumar P (2020) Gastrodia gunatillekeorum (Gastrodieae, Epidendroideae, Orchidaceae), a new species from a lowland rainforest of Sri Lanka. Phytotaxa 436(1): 55–62.
  • Imhof S (2010 onwards) Mycoheterotrophic plants – How many of them are there? [Accessed 14.11.2022]
  • Jonker FP (1938) A monograph of the Burmanniaceae. Mededeelinger van het Botanisch Museum en Herbarium van de Rijks Universiteit te Utrecht 51: 1–279.
  • Kumar P, Gale SW, Li JH, Bouamanivong S, Fischer GA (2017) Thismia nigricoronata, a new species of Burmanniaceae (Thismieae, Dioscoreales) from Vang Vieng, Vientiane Province, Laos, and a key to subgeneric classification. Phytotaxa 319(3): 225–240.
  • Larsen K, Averyanov LV (2007) Thismia annamensis and Thismia tentaculata, two new species of Thismiaceae from central Vietnam. Rheedea 17(1–2): 13–19.
  • Lim CL, Chan YC, Julius A, Yao TL, Chua LSL, Kiew R (2008) A checklist of vascular plants for the Sungai Cicir Area, Tasik Kenyir, Terengganu, Peninsular Malaysia. In: Elagupillay S et al. (Eds) Proceedings of Seminar Biodiversiti Kebangsaan 2007. 27–29 November 2007, Kuala Lumpur, 135–154.
  • Mar SS, Saunders RMK (2015) Thismia hongkongensis (Thismiaceae): A new mycoheterotrophic species from Hong Kong, China, with observations on floral visitors and seed dispersal. PhytoKeys 46: 21–33.
  • Nuraliev MS, Yudina SV, Truong BV, Do TX, Luu HT, Kuznetsov AN, Kuznetsova SP (2020) A revision of the family Thismiaceae (Dioscoreales) in Cambodia, Laos and Vietnam. Phytotaxa 441(3): 229–250.
  • Shepeleva EA, Schelkunov MI, Hroneš M, Sochor M, Dančák M, Merckx VSFT, Kikuchi IABS, Chantanaorrapint S, Suetsugu K, Tsukaya H, Mar SS, Luu HT, Li H-Q, Logacheva MD, Nuraliev MS (2020) Phylogenetics of the mycoheterotrophic genus Thismia (Thismiaceae: Dioscoreales) with a focus on the Old World taxa: Delineation of novel natural groups and insights into the evolution of morphological traits. Botanical Journal of the Linnean Society 193(3): 287–315.
  • Siti-Munirah MY, Dome N (2019) Thismia domei and T. terengganuensis (Thismiaceae), two new species, and T. javanica, a new record from Terengganu, Peninsular Malaysia. PhytoKeys 124: 123–137.
  • Siti-Munirah MY, Suhaida M, Eddie C (2022) Thismia limkokthayi (Thismiaceae): A new mycoheterotrophic species from Genting Highlands in Pahang, Malaysia. PhytoKeys 211: 1–11.
  • Siti-Munirah MY, Dome N (2022b) [in press] Thismia (Thismiaceae) in Taman Negeri Kenyir (TNK), Terengganu. In: Ahmad et al. (Eds) Proceedings of the Kenyir State Park, Terengganu Scientific Expedition. Universiti Malaysia Terengganu Press. Kuala Nerus, Terengganu.
  • Siti-Munirah MY, Dome N, Thorogood CJ (2021) Thismia sitimeriamiae (Thismiaceae), an extraordinary new species from Terengganu, Peninsular Malaysia. PhytoKeys 179: 75–89.
  • Suetsugu K, Tsukaya H, Tagane S, Chhang P, Yukawa T, Yahara T (2018) Flora of Bokor National Park VII: Thismia bokorensis (Burmanniaceae), a new species representing a new generic record. Phytotaxa 334(1): 65–69.
  • Tanaka N, Aung MM, Latt MM (2018) Thismia breviappendiculata (Thismiaceae), a new mycoheterotrophic plant from southern Myanmar. Bulletin of the National Museum of Nature and Science, Series B, Botany 44: 67–72.
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