Didymoglossum radiatum: A new species of creeping Fern from Thailand.

The genus Didymoglossum comprises about 30 species of small, generally tropical Ferns growing as epiphytes (i.e. on other Plants) or epiliths (on rocks). Roughly half of the described species come from the Old World, with eight species from tropical Asia. Five species of Didymoglossum are known from India, five from China, one from Vietnam, four from the Solomon Islands, and six from Malesia (Malaysia, Brunei, the Philippines, and western Indonesia). These Ferns, and possibly other, undescribed species, are likely to also be found in the nations between these documented areas, though as yet few, if any, studies have been carried out in these countries.

In a paper published in the journal PhytoKeys on 6 August 2025, Siwakorn Chokrassameehirun of the Department of Horticulture at Kasetsart University, Ekaphan Kraichak of the Department of Botany and Biodiversity Center at Kasetsart University, and Tassanai Jaruwattanaphan, also of the Department of Horticulture and Biodiversity Center at Kasetsart University, present a study of the genus Didymoglossum in which they describe a new species, as well as documenting other species in the country for the first time.

The new species is described from specimens collected in Hala–Bala Wildlife Sanctuary in Waeng District in the far south of Peninsula Thailand, close to the border with Malaysia. The species is named Didymoglossum radiatum, in reference to the false veinlets on the fronds of the Fern, which form a radiating pattern. 

Didymoglossum radiatum. (A) Habit; (B) Raised sori of fertile Plants; (C) Adaxial surface of sterile fronds; (D) Abaxial surface of sterile fronds; (E) False veinlet construction; (F) Sori. Siwakorn Chokrassameehirun in Chokrassameehirun et al. (2025).

Didymoglossum radiatum can be epiphytic or epilithic in nature, with a long, creeping rhizome 0.2-0.3 mm in diameter firmly anchored to the surface over which it grows by numerous dark brown hairs. It produces plate-like fronds 1.0-1.5 mm in diameter, with dense brown hairs around the rims. Each frond typically bears a single sori (spore-producing body).

Illustration of Didymoglossum radiatum. (A) Fertile frond; (B) Sterile fronds; (C) False veinlet construction; (D)–(E) Sori with tubular involucres; (D) Sori with filiform receptacle; (E) Sori borne at the notch of the frond. Siwakorn Chokrassameehirun in Chokrassameehirun et al. (2025).

Chokrassameehirun et al. also record the presence of two species of Didymoglossum in Thailand for the first time. 

The first of these is Didymoglossum henzaianum, a species which grows on rocks close to streams, which was first described from Myanmar in 2014, and which has subsequently been reported in India, Vietnam, and Peninsula Malaysia. Chokrassameehirun et al. found specimens of this species in Phu Ruea District in Loei Province, in the north of the Country.

Didymoglossum henzaianum. (A) Habit; (B) Fertile plants; (C) False veinlets on lamina segment; (D) Sori with obconic–tubular involucres. Siwakorn Chokrassameehirun in Chokrassameehirun et al. (2025).

The second new report is of Didymoglossum mindorense, a species described in the Philippines in 2006, and subsequently reported from Borneo, New Guinea, the Solomon Islands, and Queensland. Didymoglossum mindorense is found at low elevations, and typically close to streams. It is usually found growing around the bases of trees, but will sometimes colonise rocks. Chokrassameehirun et al. reporr specimens of this species in Hala–Bala Wildlife Sanctuary and the area around it.

Didymoglossum mindorense. (A) Habit; (B) Fertile fronds; (C) Lobe of sterile frond; (D) Fertile frond. Siwakorn Chokrassameehirun in Chokrassameehirun et al. (2025).

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Prunus luxurians: A new species of Cherry from southwestern Ecuador.

The genus Prunus has a worldwide distribution and contains several important food crops (including Cherries, Almonds, and Plums), ornametal species (Blossom Cherries), timber souces (e.g. Black Cherry) and medicinal Plants (e.g. African Cherry). There are thought to be about 450 valid species in the genus, but the situation is complicated with about 1230 species described within the genus, and over 2000 more in other genera that have since been synonymised with it (i.e. genera which have had all their putative members moved into Prunus. 

Historically, it has been thought that the majority of Prunus species are found in the northern temperate belt, with a smaller number of species found at high altitudes in tropical and subtropical zones. However, recent research has discovered that the genus is much more widespread in lowland tropical forests than previously realised, particularly in the Americas, raising the possibility that the genus is more diverse in these regions than in the temperate zone.

In a paper published in the journal PhytoKeys on 4 April 2025, Álvaro Pérez of the Herbario QCA at the Pontificia Universidad Católica del Ecuador, Jorge Andrés Pérez-Zabala of the Herbario Gabriel Gutiérrez Villegas at the Universidad Nacional de Colombia, Katya Romoleroux, also of the Herbario QCA at the Pontificia Universidad Católica del Ecuador, David Espinel-Ortiz, again of the Herbario QCA at the Pontificia Universidad Católica del Ecuador, and of the Bonn Institute of Organismic Biodiversity at the University of Bonn, and Chaquira Romoleroux and Natasha Albán-Vallejo, once again of the Herbario QCA at the Pontificia Universidad Católica del Ecuador, describe a new species of Prunus from southwestern Ecuador.

The new species is described from a small population of trees discovered in a cloud forest remnant in the Sambotambo Birón area of the Jocotoco Foundation-managed Reserve Buenaventura in El Oro Province, on the western flank of the Andes, between 1300 and 1400 m above sealevel. The new species is named Prunus luxurians, in reference to its 'profuse blooming and outstanding beauty', which makes it a conspicuous part of the lower and mid-strata of the forest.

Prunus luxurians: (A) Habit, (B branch with leaves and floriferous shoots, (C) flowers. Álvaro Pérez in Pérez et al. (2025).

Prunus luxurians forms trees up to 11 m high, with grooved dark brown bark with lighter lenticles (raised pores). Leaves are oblong-to-lance-shaped, waxy, and grow on alternating sides of leaf stems, they are 10–13.65 cm long and 3.5–4.65 cm wide. Flowers are white with light green centres, and born on floriferous shoots, which can have 14–27 individual flowers, clusetered together in groups of 3-4.

Only five living trees were found, in a fragment of montane evergreen forest, with high levels of bith diversity and endemism. The remaining forest fragments in this region are considered to be threatened by mining and farming activities, for which reason Pérez et al. recomend that Prunus luxurians be classified as Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species.

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Pothos deleonii: A new species of Arum from Mindanao Island.

Arums of the genus Pothos are hemiepiphytic vines (Plants which begin life as epiphytes growing upon other plants, but which as they grow stronger become self-supporting) found in tropical and subtropical forests in South China, Southeast Asia, Austrolasia, Oceana, and Madagascar. 

In a paper published in the journal PhytoKeys on 15 October 2024, Maria Melanie Medecilo-Guiang of the Center for Biodiversity Research and Extension in Mindanao and Plant Biology Division at Central Mindanao University, and Derek Cabactulan of Cagayan de Oro City, describe a new species of Pothos from Bukidnon Province on Mindanao Island, Philippines.

The new species was first noted as possibly significant on the basis of its remarkable inflorescence, by conservationist and eye surgeon Miguel De Leon at a Robert S. Kennedy Bird Conservancy site in Bukidnon Province during an ornithological expedition in 2019. A subsequent expedition to the same site in February 2024 collected samples of the plant, from which it has been confirmed to be a new species. This is named Pothos deleonii, in honour of the initial discoverer.

Pothos deleonii. (A) Habit with flowering branch, (B) leaf apex, (C) leaf base, (D) venation pattern, (E) inflorescence, (F( detail of spadix. Medecilo-Guiang & Cabactulan (2024).

Pothos deleonii is a root climbing, fibrous liana, with slender, slightly woody, green stems from which slender leaves arise on petioles (leaf stems) at regular intervals. Roots are found along the stem when the plants are young, but become less common as the Plant matures, and tend to be absent around inflorescence-producing termini. Inflorescences are born singularly on elongated peduncles (flower stalks) which hang 16-18 cm below the stem. These inflorescences are a dark wine red, aging to purplish black, with a spadix (spike with a large number of small flowers) up to 6.9 cm long, surrounded by a spathe (petal-like structure) up to 10 cm long and 5.5 cm wide.

Pothos deleonii was found growing at only two locations, climbing on the  base and trunks of Tree Ferns of the genus Alsophila, in an area of degraded secondary, open-canopy Dipterocarp forest, at altitudes of 1150 and 1270 m above sealevel. Once the vines reach about 4-6 m in height they become independent of their host, able to stand free, either on their own base or supported by the surrounding tree canopy. 

Both known sites are within a 5 km² area in the northern foothills of Mt. Kitanglad. This area is protected, and monitored by the Robert S. Kennedy Bird Conservancy, and not considered to be under any threat. However, on the basis of the low number of specimens discovered, and the limited area within which it is found, Medecilo-Guiang and Cabactulan recommend that Pothos deleonii is classified as Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species.

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Tylototriton soimalai: A new species of Crocodile Newt from Tak Province, northwestern Thailand.

Salamanders of the genus Tylototriton, known as Crocodile Newts for the scale-like knobbly protuberances on their skin, are found across the Himalayan Region, Southeast Asia, and South and Central China. There are currently 40 described species, most of which are highly endemic (have very limited distributions), with several known undescribed species in Southeast Asia. There are currently six described species from Thailand, Tylototriton verrucosus,   Tylototriton uyenoi, Tylototriton anguliceps, Tylototriton phukhaensis, Tylototriton umphangensis, and Tylototriton panhai, five of which have been described since 2013. 

In a paper published in the journal ZooKeys on 15 October 2024, Porrawee Pomchote of the Department of Biology at Chulalongkorn University, Parada Peerachidacho of the Research Institute for Languages and Cultures of Asia at Mahidol University, Wichase Khonsue also of the Department of Biology at Chulalongkorn University, Pitak Sapewisut of the Department of Biology at Chiang Mai University, Axel Hernandez of the College of Biology & the Environment at Nanjing Forestry University and the Department of Environmental Sciences at the University Pasquale Paoli of Corsica, Chitchol Phalaraksh, also of the Department of Biology at Chiang Mai University, Parunchai Siriput of the Department of National Parks, Wildlife and Plant Conservation, and Kanto Nishikawa of the Graduate School of Global Environmental Studies and Graduate School of Human and Environmental Studies at Kyoto University, describe a new species of Crocodile Newt from Mae Tuen Wildlife Sanctuary in Tak Province, northwestern Thailand.

In July 2014, Axel Hernandez discovered a male Crocodile Newt in a muddy pond in the middle of a Dipterocarp and mixed deciduous forest close to the top of Doi Soi Malai (Mount Soi Malai), about 1500 m above sealevel. He initially assigned this to Tylototriton uyenoi, a species which had been described the previous year from the same area. However, subsequent examination of the specimen showed that it differed from Tylototriton uyenoi in a number of ways. In 2015 the Tourism Authority of Thailand published a video clip on the MGR Online platform showing Crocodile Newts at the same location. This led to a field study of the area in August 2022, during which three adult male Crocodile Newts and two tadpoles were discovered in a muddy puddle in a road on Doi Soi Malai, again at about 1500 m above sealevel.

Pomchote et al. carried out both genetic and morphological analysis of the Doi Soi Malai specimens, both of which led them to conclude that they were representatives of a new species. This is named Tylototriton soimalai, in reference to the location where it was discovered, Doi Soi Malai.

The male holotype of Tylototriton soimalai (CUMZ-A-8253) observed at the type locality. Pomchote et al. (2024).

The known specimens of Tylototriton soimalai are medium-sized Crocodile Newts, ranging from 90.7 mm to 109.3 mm in length, with and are black in colour (dark grey on the underside), with two orange ridges on either side of the dorsal surface of the skull, behind which are two rows of orange nodules which follow the length of the body, but not the tail, while a third, solid orange ridge follows the length of the spine, including the tail.

The two tadpoles vary in size, with one roughly double the size of the other, despite being found at the same time. In both, the head is large with visible eyes, and three pairs of reddish-brown external gills.  The tadpoles are pale brown in colour with scattered black markings, and purple-silver markings around the eyes and fin, and on the flanks.

The two larvae of Tylototriton soimalai in life. Pomchote et al. (2024).

All of the specimens were found in a muddy puddle roughly 10 m long and 5 m wide, with a maximum depth of about 35 cm. They were found at about midday on 31 August 2022, which is in the rainy season; this is presumed to be the breeding season of the Newts. The puddle is located on a road running over Doi Soi Malai, with the exact location not given to protect the species from illegal collection.

Pomchote et al. note that the road is extensively used by mountain bike and four-wheel-drive enthusiasts, particularly during the monsoon season, despite these activities being banned in national parks and wildlife sanctuaries in Thailand by the Department of National Parks, Wildlife and Plant Conservation. For this reason, Pomchote et al. recommend that the road should be closed off completely during the monsoon season, remaining open to hikers during the dry and winter seasons. They also note that the environment both within and around the Mae Tuen Wildlife Sanctuary has been degraded by deforestation and fragmentation for agricultural use, primarily cabbage farming. They therefore recommend that Tylototriton soimalai be listed as Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. 

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Thismia malayana: A new species of Parasitc Plant from Peninsula Malaysia.

Thismias, Thismia spp., are a curious group on Monocotyledonous Plants found in the evergreen forests of tropical and subtropical Asia, northern and eastern Australia to New Zealand, the north-central USA, Costa Rica and southern tropical America. They are Mycoheterotrophs, obtaining nutrition parasitically from the network of Mycorrhizal Fungi which exchange nutrients with the Plants of the forest, but contributing nothing themselves to the relationship. Thismias do not photosynthesize, enabling them to live on the darkest parts of the forest floor, and live most of their lives below ground, occasionally producing intricate, but often inconspicuous, flowers at most a few centimetres high, which are pollinated by Fungus Knats or similar small Insects.

In a paper published in the journal Phytotaxa on 31 May 2024, Mat Yunoh Siti-Munirah of the Forest Research Institute Malaysia, independent researchers Chin Hardy-Adrian, Sharipudin Mohamad-Shafiq, and Zainuddin Irwan-Syah, and Abd Halim Hamidi of the Negeri Sembilan Forestry Department, describe a new species of Thismia from Peninsula Malaysia.

The new species is named Thismia malayana, where 'malayana' is derived from 'Malaya' the old name for Peninsula Malaysia. The species is described from a specimen collected in the Kuala Pilah District of Negeri Sembilan State, Malaysia, on a trail leading to Gunung Angsi mountain, in February 2023.

Thismia malayana (A) flowering plant (A1) floral tube, inner surface (A2) annulus and stamen filaments, view from inside (B) inflorescence with anthetic flower and several young fruits (B1) style and stigma (B2) annulus, top view (C) flower, side view (D), (E) stamens, view from inside and from outside, (E1) stamen supraconnectives: one pair of club-shaped inwards-pointing, one pair of acute outwards-pointing, and one central appendage (F) stamen supraconnectives, apical view (G) stamen tube, view from below (H), (H1) fruit after dehiscence, top view, (H2) seeds I shoot base with roots. Siti-Munirah et al. (2024).

Thismia malayana exists as a vermiform root, light brown, unbranching and about 1 mm in diameter, which produces a light brown herbaceous Plant, reaching a maximum height of about 10 cm. This above-ground Plant comprises a stem about 6 cm long and 0.2 cm in diameter, from which grow 2-4 scale-like brown leaves, and 1-4 asymmetrical, tube-shaped flowers, up to about 7 mm long and 5 mm in width, brown-to-off-white in colour, with orange longitudinal ribs, and an opening surrounded by six triangular tepals. 

Thismia malayana with scales (the finest grade is 0.5 mm) (A) side view (B) top view (C) the size compared to the 20-sen coin (23.59 mm in diameter). Photos by Chin Hardy-Adrian from uncollected plants. Siti-Munirah et al. (2024).

 

Thismia malayana is known from only two localities, one in the Gunung Angsi Forest Reserve in Negeri Sembilan State, and the other in Tengku Hassanal Wildlife Reserve in Pahang State. In both locations it grows in moist, shady areas of Diptocarp forests, at elevations of 200-450 m above sealeavel, usually producing flowers and fruit between December and February (although flowering in June has also been observed). 

Habitat (in situ) of Thismia malayana in Ulu Bendul Recreational Park in Gunung Angsi Forest Reserve (A), (B) and the Tengku Hassanal Wildlife Reserve (C)–(E). (A) Thismia malayana at its habitat, which is located right next to the main trail to Gunung Angsi. (B) Mat Yunoh Siti-Munirah showing the habitat of Thismia malayana. (C) Path to Lata Bujang and Gunung Benom (D) The plants growing on rotten wood (E) Sharipudin Mohamad-Shafiq observing a Thismia malayana in its habitat. Photos by Mat Yunoh Siti-Munirah (A), (B) and Sharipudin Mohamad-Shafiq (C)–(E). Siti-Munirah et al. (2024).

Thismia malayana is known only from two locations, with less than 10 individual Plants observed. Both locations are in protected areas, although on is quite close to a forest trail, where it might be disturbed by visitors. The species is extremely cryptic in nature, making it likely that is exists in other areas and has not been discovered. For these reasons, Siti-Munirah et al. recommend that the species be classified as Vulnerable under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. 

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