Gastrodia queenslandica Dockrill, a mycoheterotrophic orchid, was previously recorded from eastern Queensland, Australia. We recently encountered populations of Gastrodia R.Br. in Singapore and Thailand which appear to be conspecific with G. queenslandica. In 1889, Ridley collected this species in fruit from Singapore, but he incorrectly identified them as Didymoplexis pallens Griff. We present a comprehensive analysis including a detailed description, line drawing, colour plates, and notes on taxonomy and ecology. We assembled the plastome of Gastrodia queenslandica from Singapore, which is 29,498 bp in size, notably the smallest plastome recorded in the genus.

Didymoplexis micradenia (Rchb.f.) Hemsl. is newly recorded from Singapore. The species is widespread in Asia and Oceania, with a notable increase in recorded range in recent years. We consider this species native to Singapore. This is also a new generic record for Singapore, as all previous records of the related Didymoplexis pallens Griff. from Singapore have now been reidentified as Gastrodia queenslandica Dockrill.

Besides the now common Selenicereus undatus (Haw.) D.R.Hunt (previously listed as Hylocereus undatus (Haw.) Britton & Rose), Epiphyllum hookeri Haw. is also now newly reported here as a casual species of Cactaceae in Singapore’s flora.

A discussion is given of the doubtful presence in Peninsular Malaysia of several species of Mangifera L. that were considered by Kostermans & Bompard (1993) to occur there. In addition, 43 names in several genera of the Anacardiaceae that do grow in Peninsular Malaysia are lectotypified, and one name, Campnosperma coriaceum Jack, is neotypified.

A discussion is given of the doubtful presence in Peninsular Malaysia of several species of Mangifera L. that were considered by Kostermans & Bompard (1993) to occur there. In addition, 43 names in several genera of the Anacardiaceae that do grow in Peninsular Malaysia are lectotypified, and one name, Campnosperma coriaceum Jack, is neotypified.

A new ornamental species of Homalomena Schott, H. polyneura A.S.D.Irsyam & M.R.Hariri, is formally described from Central Papua, Indonesia.

Clerodendrum kelli R.Bustam., A.B.Tobias & Ples—a new species of the genus Clerodendrum L. (Lamiaceae) from the montane forests of Carranglan, Nueva Ecija, Luzon Island, Philippines—is described and illustrated. The species shares morphological features that are uncommon for the genus with both Clerodendrum quadriloculare (Blanco) Merr. (purple abaxial leaf surfaces) and C. mindorense Merr. (reduced fruiting calyx lobes), but differs from both in having lax (vs dense/compact) inflorescences bearing flowers with shorter corolla tubes and reddish-pink (vs green or purple) calyces with ovate (vs triangular or lanceolate) lobes. Additionally, a lectotype for C. mindorense is assigned. Preliminary assessment of its conservation status following IUCN guidelines places Clerodendrum kelli in the category of Critically Endangered (CR B1ab(iii)+2ab(iii)).

Bulbophyllum placochilum J.J.Verm., endemic to Borneo, is newly recorded in the Philippines based on a specimen collected from Mt Malinao, Albay Province, Luzon Island. We provide a comprehensive account of the species, including a detailed morphological description, ecological observations, distribution range, phenology, and photographs. The species is assessed as Vulnerable under the IUCN Red List Categories and Criteria. A key to species of Bulbophyllum sect. Altisceptrum J.J.Sm. in the Philippines is also included.

Curcuma corallina N.S.Lý & Škorničk., a new ginger species discovered in the south-central region of Vietnam, is described here with colour plates and notes on its distribution, habitat, phenology, etymology, and a preliminary IUCN conservation assessment. It is placed in Curcuma subg. Ecomatae Škorničk. & Šída f. and, for diagnostic purposes, is compared to C. rhomba Mood & K.Larsen, which is superficially similar in overall plant habit, a lack of bracteoles, and flower colour, but differs in rhizome structure, and the shape, size and colour of various floral parts.

Munronia assamica S.Dey & Bhaumik, a new species is described and illustrated from the Kopili River Basin, Dima Hasao District of Assam, India. The new species is morphologically similar to IAver. & K.S.Nguyen. A detailed taxonomic description, illustration, field photos and comparison with the nearest species are provided to aid its recognition. A phylogenetic analysis was also carried out to confirm its taxonomic position.

We report three novelties for the genus Hoya R.Br. in Arunachal Pradesh based on recent fieldwork: Hoya dawodiensis Sahani, Rodda, Pertin & Chowlu, sp. nov., most similar to Hoya acuminata Benth. ex Hook.f. but mainly separated on the shape of the corona, the first Indian record of H. yingjiangensis J.F.Zhang et al., and a new state record of H. nummularia Decne. ex Hook.f. In addition, Hoya obcordata Hook.f. and H. tengchongensis J.F.Zhang et al. are synonymised with H. nummularia, and the former is typified.

A thorough search of literature reveals that the type of Bauhinia cardiophylla Merr. is deposited at PNH but it was erroneously assumed to be at A. The earlier holotype citation of the name is corrected here to lectotype. Additionally, Bauhinia williamsii F.Muell. is lectotypified here.

The discovery of Phyllodon lingulatus (Cardot) W.R.Buck among several existing herbarium specimens collected from Singapore represents a new species record for the country. Additionally, the genus Phyllodon and the family Symphyodontaceae are both new records for Singapore. Phyllodon bilobatus (Dixon) P.E.A.S.Câmara is treated as a new synonym for P. lingulatus.

A population of Grona harmsii (Schindl.) H.Ohashi & K.Ohashi is discovered in Singapore. The species was previously known only from the coastal areas in Vietnam, and this is the first known occurrence outside its native range. The discovery, albeit non-native, represents a new species record to Singapore.

Five non-indigenous species, viz. Hamelia patens Jacq. (Rubiaceae), Laportea aestuans (L.) Chew (Urticaceae), Leuenbergeria bleo (Kunth) Lodé (Cactaceae), Tradescantia spathacea Sw. (Commelinaceae) and Triphasia trifolia (Burm.f.) P.Wilson (Rutaceae), are reported here as new records of naturalised species or species of casual occurrence in Singapore. Hamelia, Leuenbergeria, Tradescantia and Triphasia are also new generic records for the naturalised flora of Singapore.

Five species and one genus of Amaranthaceae are newly recorded for Singapore, all being either non-native, naturalised, casual or cryptogenic species. A lectotype is designated for Chamissoa esculenta Moq., a synonym of Allmania nodiflora (L.) R.Br. ex Wight. In Crassulaceae the status of Bryophyllum Salisb. is clarified and a lectotype is designated for Cotyledon pinnata Lam.

Recent collections from Kapit, Sarawak (Borneo), have revealed several new species of stoloniflorous figs (earth figs). These plants bear their figs on ground-level or subterranean stolons rather than on aerial stems and have therefore been under-collected, appearing sterile to those who do not know to look at the ground. This study presents four newly described species (Ficus aureopilosa E.M.Gardner, F. pulchrifolia E.M.Gardner, F. rubrostellata E.M.Gardner, and F. salangii E.M.Gardner), one new variety (F. subterranea Corner var. pubescens E.M.Gardner), and one new name for a variety elevated to species level (Ficus pseudobeccarii E.M.Gardner = F. beccarii King var. latifolia Corner). We also provide a revised key and taxonomic notes for the earth figs of Kapit.

A new species, Begonia subaequifolia Y.P.Ang & J.Collantes, is here described and illustrated from Luzon Island, Philippines. It closely resembles Begonia jagori Warb. by having an upright habit, stems covered with short brown hairs, short petioles, and an elliptic lamina with an oblique and shallowly cordate base. However, Begonia subaequifolia is distinct by having smaller stipules, sub-symmetrically oblong-ovate to narrowly elliptic-ovate lamina with pinnate venation, a crenate or serrulate leaf margin, the staminate inflorescence in a dichasial cyme, and smaller tepals in staminate flowers. We also report the rediscovery of B. loheri Merr., a poorly known Philippine endemic Begonia species, and provide an amended description, lectotypification, and photographs.

A new species, Habenaria diwata R.Bustam., J.Collantes & M.R.B.Altamirano (Orchidaceae: Orchidoideae), is described from Mount Malinao, Luzon Island, Philippines. Habenaria diwata most closely resembles the Taiwanese species H. tsaiana T.P.Lin in having bipartite petals with an entire posterior lobe and a tripartite labellum with an entire mid-lobe and subdivided side lobes, but differs by its shorter lateral sepals (9–11 mm long vs 12.5–13.5 mm long in H. tsaiana), anterior petal lobes that are mostly entire, with the lower margin lacerate or unequally bifid at the apex (vs subdivided into two segments), shorter labellum base (1 mm vs 1.5–2 mm) and labellum side lobes subdivided into two filiform segments (vs subdivided into three filiform segments). Differences of H. diwata from a similar Philippine species, H. lingulosa Ames, are briefly discussed. This discovery raises the current number of recognised Habenaria species in the Philippines to 22. Illustrations and information on its distribution, habitat, phenology, and proposed conservation status are provided.

Newmania bambusifolia Škorničk., Vuong & Bao (Zingiberaceae: Zingiberoideae), a new ginger species discovered in Hon Ba Nature Reserve, Khanh Hoa Province in southern Vietnam is described and illustrated here with notes on distribution, ecology, phenology, preliminary IUCN assessment, and etymology. It is distinct from all known congeners by the very narrow leaf-blades, resembling those of bamboos. This discovery increases the total number of species in Newmania to seven. We include an updated key to the genus accommodating this novelty.

After new field observations and a review of literature and herbarium specimens, three new species of Begonia sect. Platycentrum from Southwestern China are described and illustrated here: Begonia zhuhaiensis D.K.Tian and B. shunanensis D.K.Tian from Sichuan Province, and B. qianchuanensis D.K.Tian & Z.L.Chen from Guizhou and Sichuan Provinces. The new species are morphologically compared with allied species, and their conservation status is assessed according to the IUCN Red List Categories and Criteria.

Agapetes athangensis P.Gyeltshen, a new species from the warm broad-leaved forest of Athang Block in Wangdue District, Bhutan is described and illustrated. The new species is assigned to Agapetes D.Don ex G.Don sect. Agapetes owing to its free filaments and calyx articulated at the junction with the pedicel, and to ser. Agapetes as it has stout stems, pseudowhorled leaves, and 5-lobed, glandular-capitate stigma. The new species is similar to Agapetes auriculata (Griff.) Benth. & Hook.f. in having an angular calyx and corolla, and capitate stigma, but differs by the pubescent inflorescence, longer pedicels, and tubular corolla tube. It differs from Agapetes sikkimensis Airy Shaw by the racemose or sub-corymbose inflorescence, longer peduncle, and calcarate stamens. Due to inadequate information on population abundance and distribution, the species is currently assessed as Data Deficient (DD).

A new species, Strobilanthes sherdukpenorum D.Borah & J.R.I.Wood, is described from Arunachal Pradesh in the East Himalayas. The new species is illustrated with original photographs and its salient characteristics are indicated. It enjoys a degree of protection because of its presence in the Kameng Protected Area Complex.

Accurate botanical illustrations play a crucial role in plant identification. Hoya macrophylla Blume, one of the earliest described species of Hoya R.Br. from Southeast Asia, and among the earliest to be illustrated, presents significant identification challenges. This paper elucidates how its first illustration incorporates features characteristic of both Hoya macrophylla and H. latifolia G.Don, and this is the reason behind the difficult application of the name. Furthermore, the type specimen of Hoya macrophylla is indistinguishable from H. cinnamomifolia Hook., a taxon published later and consistently correctly applied. This study underscores the need for careful re-evaluation of historical illustrations in the context of modern taxonomic standards. A lectotype and an epitype are designated for Hoya macrophylla and H. latifolia respectively and their synonyms are clarified and where necessary typified.

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The conservation status of orchids in the city-state of Singapore mirrors the worldwide decline of this group of plants, one of the largest families of flowering plants.Despite this, the number of extant native orchids has been revised from 45 to 76 in the last 15 years largely due to taxonomic revisions and (re-)discoveries. Building on the history of orchid taxonomic research in the Singapore Botanic Gardens and the revival of plant systematics in Singapore, these recent successes reflect efforts in establishing resident taxonomists and field ecologists, embracing integrative taxonomy, undertaking comprehensive botanical surveys, and developing an opportunistic instinct to discover orchids in the field. Coupled with ongoing species recovery efforts, this provides a sense of optimism for conservation and suggests that small habitat fragments characteristic of cities could continue to be refugia for native orchids. This also further illustrates the important role that botanic gardens play in the conservation of endangered plant species

Many names in the Euphorbiaceae, Phyllanthaceae, Picrodendraceae, Rutaceae and Sapindaceae are lecto- or neotypified. In some cases, these typifications have also enabled the resolution of nomenclatural problems (in Acer laurinum Hassk., Baccaurea racemosa (Reinw.) Müll.Arg., Dimocarpus lichi Lour.). The status of Nymphanthus glaucescens (Miq.) R.W.Bouman (Phyllanthaceae) is reassessed as cryptogenic in Singapore

A few taxonomic and nomenclatural aspects of the genus Oberonia Lindl. relating to the Flora of Singapore are resolved. First, no subgeneric names are recognised in the genus Oberonia. Oberonia subg./sect. Apothemnophyllum Schltr. and Oberonia subg./sect. Menophyllum are synonyms of Oberonia s.s. The autonymous subgenus is a non-mandatory rank, hence, can be omitted. Second, Oberonia hamadryas Ridl. is the correct name for O. scortechinii Hook.f., and the lectotype of Hippeophyllum is here corrected to Hippeophyllum micranthum Schltr. Third, additional species-level synonyms are established for O. equitans (G.Forst.) Mutel (O. hispidula Ames, syn. nov.), O. lunata (Blume) Lindl. (O. wenzelii Ames, syn. nov.), and O. jenkinsiana (O. austro-yunannensis S.C.Chen & Z.H.Ji, O. clarkei Hook.f., O. elbertii Ridl., O. flabellifera Holttum, O. multidentata Aver., O. polyschista Schltr., O.quadridentata Aver., O. rhizophoreti Schltr., O. stenophylla Ridl., O. sumatrana Schltr., O. sumatrana var. endertii Ridl., syn. nov.). Fourth, the specimen K000943003 is here designated as second-step lectotype of Oberonia biaurita Hook.f., and simultaneously also as epitype of O. lunata.

Two species of Phytocrene Wall. are recorded for Singapore: the widespread and commonly collected species P. bracteata Wall., and P. oblonga Wall., known from a single collection from Nee Soon Swamp Forest in the Central Catchment Nature Reserve. Phytocrene bracteata is also cultivated in Singapore Botanic Gardens. The typification of each name is addressed, and a key to the two species, descriptions, an illustration of P. oblonga as well as photographs of both species are provided.

Further work on the genus Piper L. in Singapore has led to the need for a number of nomenclatural and taxonomic clarifications. Lectotypes are designated for ten names: Piper flavimarginatum C.DC., P. pachyphyllum Hook.f., P. crassipes Korth. ex Miq., Cubeba neesii Miq., P. burkillii Ridl., P. lanceolatum Roxb., P. ridleyi C.DC., P. velutibracteum C.DC., P. rostratum Roxb., and P. sarmentosum Roxb. A neotype is designated for P. latifolium W.Hunter, and previous confusion in the literature is clarified.

Bulbophyllum bonjolianum Yudistira, Candra & Mustaqim, a member of section Macrocaulia, is described here based on a specimen collected from the mountains of West Sumatra. It is similar to B. tristriatum Carr. and B. pyridion J.J.Verm. but differs in the morphology of the dorsal sepal, petal and labellum. A key to B. bonjolianum and morphologically similar species is presented.

Two species of Cryptocarya R.Br. are newly described for New Guinea. Both are shrubby to subarborescent lowland species bearing large leaves. Cryptocarya azurea Ezedin is described from the Sepik-Ramu basins, separated out from material formerly identified as C. magnifolia Teshner, whereas C. hydrantha Ezedin, recorded from Jayapura to Josephstaal, is validated based on an unpublished name.

A new species of Primulina Hance (Gesneriaceae), P. serina F.Wen & W.C.Chou from northern Guangxi, China, is described and illustrated. It is morphologically similar to P. versicolor F.Wen, B.Pan & B.M.Wang, but can be easily distinguished by its smaller bracts. In its natural habitat, this species exists only in two subpopulations, and they occupy an area of less than 40 m2 and, following IUCN guidelines, this new species is provisionally assessed as Critically Endangered (CR).

Arunachal Pradesh in northeastern India hosts a diverse array of Strobilanthes Blume species. The occurrence of two previously unreported species, Strobilanthes pubiflora J.R.I.Wood and S. paniculiformis J.R.I.Wood, is documented. Strobilanthes siangensis J.R.I.Wood, Gammi & D.Borah is described as new and discussed in detail. A key to similar species is provided for identification purposes. The paper is illustrated with a map and photographs.

No abstract

No abstract

Orania sylvicola (Griff.) H.E.Moore is a large, single-stemmed palm species widely distributed across Malesia. It is the only species of Orania present in Peninsular Malaysia and Singapore. In Singapore, the species is rare and critically endangered, although a full understanding of its distribution is hampered by sparse historical collections. However, conflicting records on the known localities in the literature, along with a recent discovery of a substantial population of Orania sylvicola within the Tyersall Learning Forest in Singapore Botanic Gardens, have led to questions on the origin of the extant populations of O. sylvicola. There are known instances of past introductions of non-native plant species in Singapore, which raised suspicions that some of the individuals were historical reintroductions from overseas. Genetic analyses, a comprehensive survey of existing literature and herbarium collections, and a topographical study of existing Orania sylvicola populations were carried out to determine the origin of these individuals in Singapore. Our results suggested that all Orania sylvicola individuals in Singapore are of native origin, with two populations present. The distribution of the two populations overlaps in the Singapore Botanic Gardens, which may indicate that someof the plants have been transferred to the Botanic Gardens from another location in Singapore. Preliminary results also revealed that sampled populations within Peninsular Malaysia and between Peninsular Malaysia and Singapore are highly differentiated from each other with very little gene flow either by pollen or seed dispersal. Our study highlights how the integration of genetic information, historical collections and topographical analyses can contribute to assessing the origin and conservation potential of endangered plant species in Singapore and provide insights into suitable conservation actions for Orania sylvicola.

Monoecious Ficus L. (Moraceae) species have putatively effective long-distance pollen dispersal and low population densities. The lack of spatially defined populations and the assumption of high gene flow led to the dearth of work on the Spatial Genetic Structure (SGS) of monoecious species. Furthermore, as only forest or inland species were studied, the effects of landscape heterogeneity and discontinuous habitats have been overlooked. To address this, Ficus superba (Miq.) Miq., a monoecious spatially aggregated coastal and insular species from Singapore, was studied to ascertain if population homogenisation could result from pollen flow even when the assumptions of spatial and landscape homogeneity were violated. Individuals were genotyped using dominant Amplified Fragment Length Polymorphism (AFLP) markers. Bayesian clustering software and Principal Component Analysis (PCA) were used to test for population genetic structure. SGS analyses and Mantel’s Tests were performed to test for the presence of significant fine-scale SGS and Isolation By Distance (IBD). Significant population genetic structure and SGS were found, with one mainland population more differentiated from the remaining insular and mainland populations. It is hypothesised that the spatial aggregation and landscape heterogeneity significantly distort gene flow through aggregated seed dispersal and greater impedance to pollen flow over land than sea. This calls into question the supposed dichotomy in gene flow characteristics of monoecious versus dioecious figs attributed to pollinator behaviour.

Eight species of Ectropothecium Mitt. previously reported and misapplied in Singapore have been critically investigated, which resulted in different reinterpretations and taxonomic reshufflings of several taxa, and discovery of new records for Singapore. Two native species, Ectropothecium monumentorum (Duby) A.Jaeger and E. tutuilum (Sull.) Mitt. (with E. ichnotocladum (Müll.Hal.) A.Jaeger and E. moritzii A.Jaeger as newly proposed synonyms) remain recognised in the genus. Ectropothecium stigmophyllum Broth. is a non-native species newly recorded in Singapore. Ectropothecium singapurense Dixon is transferred to Calohypnum Sakurai as C. singapurense (Dixon) S.He & B.C.Ho, and continues to be treated as a species endemic to Singapore. Ectropothecium buitenzorgi auct. non (Bél.) Mitt. and E. incubans auct. non (Reinw. & Hornsch.) A.Jaeger were misapplied names for the native Neoptychophyllum dixonii (M.Fleisch.) S.He & B.C.Ho. Crepidophyllum modestum Herzog (reported for the first time with sporophytes for the genus) is a non-native record new to the country. Calohypnum, Crepidophyllum Herzog and Neoptychophyllum S.He represent new generic names for Singapore. Ectropothecium intorquatum (Dozy & Molk.) A.Jaeger and E. zollingeri (Müll.Hal.) A.Jaeger are excluded from Singapore. Additionally, Ectropothecium sodale (Sull.) Mitt. was found only in cultivation; thus, it is not treated in the flora. Lectotypes are designated for Ectropothecium moritzii A.Jaeger, E. moritzii var. stereodontoides Dixon, Hypnum ichnotocladum Müll.Hal., and Hypnum monumentorum Duby. New combinations are proposed in Calohypnum and Neoptychophyllum.

An outline of the native and naturalised members of the Rosaceae occurring in Singapore is presented including synonymy and typification. Lectotypes are designated for 16 names.

The family Viburnaceae is represented by one species in the native flora of Singapore: Viburnum sambucinum Reinw. ex Blume. The nomenclature and typification of family, generic, specific and varietal names relevant to the Flora of Singapore are reviewed. Three lectotypes are designated, two at the second step.

A nomenclatural synopsis, including typification, of the native species of Menispermaceae in Singapore is presented. Fourteen species in 12 genera are included. Lectotypes are designated for 37 names, and one epitype is designated. A key to the Singapore species of Menispermaceae is also included.

Durio perakensis Salma is described (together with a diagnosis) and typified to meet the requirements of the International Code of Botanical Nomenclature.

Two new species, Codonoboea fraserensis Kiew (Gesneriaceae) and Curculigo elegantissima Kiew & Škorničk. (Hypoxidaceae) from Fraser’s Hill (Bukit Fraser), Pahang, Peninsular Malaysia are described and illustrated here. Notes on distribution, ecology and etymology are given. Both species are currently considered endemic in the area with provisional IUCN conservation assessments of Endangered and Vulnerable respectively.

The nomenclature and typification of the species of Ericaceae in Singapore are discussed. A neotype is designated for Leucopogon malayanus Jack. Lectotypes are designated for Rhododendron longiflorum Lindl., R. javanicum (Blume) Benn. var. tubiflorum Hook.f., Vaccinium bracteatum Thunb. and, in a second step, V. malaccense Wight.

In the New Guinea region, including the Solomon Islands and Halmahera, three species of the pantropical genus Xylopia L. have been previously recognised: X. calosericea Diels, X. papuana Diels, and X. peekelii Diels. In recent floristic tabulations the genus has thus comprised a minor component of the Annonaceae flora. Here we present descriptions and illustrations of 14 new species of the genus from the region: Xylopia aenea D.M.Johnson & N.A.Murray, X. ampla D.M.Johnson & N.A.Murray, X. brunneola D.M.Johnson & N.A.Murray, X. bullata D.M.Johnson & N.A.Murray, X. chlorosperma D.M.Johnson & N.A.Murray, X. cornuta D.M.Johnson & N.A.Murray, X. corrugata D.M.Johnson & N.A.Murray, X. makiraensis D.M.Johnson & N.A.Murray, X. musella D.M.Johnson & N.A.Murray, X. pachysericea D.M.Johnson & N.A.Murray, X. rogstadii D.M.Johnson & N.A.Murray, X. sulangwane D.M.Johnson & N.A.Murray, X. takeuchii D.M.Johnson & N.A.Murray, and X. vulcanicola D.M.Johnson & N.A.Murray. We distinguish the 17 species in a diagnostic key. The region includes Xylopia species that are among the tallest in this genus of c. 220 species, one with the largest leaves and another with the largest fruit, as well as several species with distinctive cataphyll-covered resting buds. The genus has undergone multiple dispersals both to and within the region, with higher diversity on smaller islands than on New Guinea. Its presence on oceanic islands indicates over-water dispersal.

The tree species Morinda bracteata Roxb. is here confirmed for New Guinea after having been previously overlooked. A brief summary of its taxonomic history is given, along with its revised distribution which now appears restricted to the east of Huxley’s Line when Palawan is included.

The genus Codonoboea Ridl. (Gesneriaceae: Didymocarpoideae: Trichosporeae: Didymocarpinae) is revised for Thailand. Thirteen species are recognised, one of which, Codonoboea poopathii D.J.Middleton, is new to science and three of which, C. dawnii (Kiew) Kiew, C. oreophila Kiew ex C.L.Lim and C. urticoides (A.Weber) Kiew, are new records for Thailand. Didymocarpus reptans Jack is neotypified; D. hispidus Ridl. var. selangorensis Ridl., D. inaequalis Ridl., D. rugosus Ridl. and D. urticifolius Ridl. are lectotypified; and D. hispidus Ridl. is lectotypified in a second step. A key to the species is provided and all species are described.

The new species Allocheilos villosus B.L.Burtt ex D.J.Middleton, Didymocarpus tamdaoensis D.J.Middleton, Didymocarpus dalatensis D.J.Middleton and Loxostigma vietnamensis D.J.Middleton from Vietnam are described.

The new species Paraboea babae D.J.Middleton from Shan State in Myanmar is described and illustrated.

The new species Kopsia obscura D.J.Middleton in the Apocynaceae is described.

A new combination Gynochthodes wongiana (Suratman) W.W.Seah is proposed here based on Morinda wongiana Suratman and the name Gynochthodes suratmanii K.M.Wong & Razafim. is placed in its synonymy.