[Botany • 2026] Argostemma baotingense (Rubiaceae) • A New Species from Hainan Island, South China

 

Argostemma baotingense S.P.Dong & H.B.Yang, 

 in Dong, Yuan, Wang et Yang, 2026. 

DOI: doi.org/10.3897/phytokeys.276.195404 

Abstract

Argostemma baotingense, a new species of Rubiaceae from Hainan Island, southern China, is described. This new species resembles A. bachmaense but can be distinguished by its suberect or creeping stem, linear leaves with a greenish-white abaxial surface, white and glabrous inflorescence, and glabrous calyx. An identification key and photographs of the nine Argostemma species in China are provided.

Key words: Argostemma, new species, taxonomy

Argostemma baotingense.
A. Plant in natural habitat; B. Flowering plant; C. Flowers; D. Calyx; E. Leafy branch, adaxial view; F. Leafy branch, abaxial view; G. Leaves, adaxial view; H. Leaves, abaxial view; I, J. A node with opposite leaves and stipules; K. Flower, apical view; L. Flower, bottom view; M, N. Inflorescence; O. Androecium; P. Pistil.

Argostemma baotingense S.P.Dong & H.B.Yang, sp. nov.

Diagnosis. The new species is morphologically similar to A. bachmaense T.V.Do but differs by the suberect or creeping stem (vs. erect), the linear leaves (vs. oblanceolate to spatulate), glabrous inflorescence (vs. pubescent), glabrous calyx (vs. pubescent). A detailed morphological comparison between the two species is provided in Table 1. Photographs of seven Argostemma species in China have been provided (Fig. 2). A key to all the nine species of Argostemma in China is also provided at the end of the text.

Shu-Peng Dong, Lang-Xing Yuan, Qing-Long Wang and Hu-Biao Yang. 2026. Argostemma baotingense (Rubiaceae), A New Species from Hainan Island, South China. PhytoKeys. 276: 253-260. DOI: doi.org/10.3897/phytokeys.276.195404   [18 Jun 2026]

[Botany • 2026] Ophiorrhiza xishuiensis (Rubiaceae) • A New Species endemic to Guizhou, Sichuan, and Chongqing, China

 

Ophiorrhiza xishuiensis Sheng H.Tang, Jia W.Yang & X.Z.He,   

in He, Dai, Xu, Yang et Tang, 2026. 

 DOI: doi.org/10.3897/phytokeys.275.189435 

Abstract

A new species in Rubiaceae, Ophiorrhiza xishuiensis, is described from China. The new species is endemic to the Danxia landform at the juncture of Guizhou Province, Sichuan Province, and Chongqing City. It is a herb with a 1–7 cm long rooting stem, 3–11 nodes, and most leaves arranged in markedly unequal pairs. It has a somewhat inequilateral leaf blade base, a congested-cymose inflorescence, and well-developed bracteoles. We investigated two populations in Guizhou, China. The new taxon has been collected or photographed by others in Sichuan and Chongqing, China, and misidentified as O. japonica, O. umbricola, O. cantonensis, or O. chinensis. An identification key to O. xishuiensis and morphologically similar species is provided.

Key words: Danxia landform, flora of China, new taxon, Ophiorrhiza

Habitat of Ophiorrhiza xishuiensis sp. nov.
A, B. Population of Sanchahe Town, Xishui County, China; C, D. Population of Baoyuan Town, Chishui City, China

 (Photographed by Sheng-Hu Tang and Xuan-Ze He).

Ophiorrhiza xishuiensis Sheng H.Tang, Jia W.Yang & X.Z.He, sp. nov.

 

Diagnosis. The new species is most similar to O. japonica, O. guizhouensis, and O. chinensis by the length of the stipules, calyx lobes and corolla tube, the shape of the corolla, and the distribution areas and altitudes. It differs from O. japonica and O. guizhouensis by the 1–7 cm long rooting stems (vs. 10–30 cm, or longer), the fact that most leaves are arranged in markedly unequal (vs. subequal) pairs, the style reaching above (vs. below) the middle of the tube in the short-styled flowers, and the glabrous (vs. pubescent) style in the long-styled flowers. It is distinct from O. chinensis by the congested-cymose (vs. paniculiform to cymose) inflorescences, the well-developed and persistent (vs. absent or reduced and caducous) bracteoles, and the glabrous (vs. pubescent) style in the long-styled flowers.

 Xuan-Ze He, Zheng-Xian Dai, Jian Xu, Jia-Wen Yang and Sheng-Hu Tang. 2026. Ophiorrhiza xishuiensis (Rubiaceae), A New Species endemic to Guizhou, Sichuan, and Chongqing, China. PhytoKeys. 275: 163-176. DOI: doi.org/10.3897/phytokeys.275.189435 [29 May 2026]

[Botany • 2026] Lasianthus sondangii (Rubiaceae) • A New Species with a unique spiciform inflorescence from Central Vietnam

Lasianthus sondangii Bao, Vuong & V.C.Nguyen, 

in Tran, V. C. Nguyen, Luong, Phan-Thi, H. T. Nguyen, Truong et Q. B. Nguyen, 2026. 

taiwania.ntu.edu.tw/abstract/2193

Abstract

Lasianthus sondangii, a new species from Lasianthus section Nudiflorae, is described from Khanh Hoa Province, Central Vietnam. It can be distinguished from other Lasianthus species in Vietnam and surrounding countries by having narrowly triangular stipules, spiciform inflorescences with two or three reduced cyme secondary axes, purple flowers, and clavate calyx lobes with revolute margins. A detailed description of the new species, color plates, distribution, habitat and preliminary conservation assessment are provided.

Keyword: Indochina, Khanh Hoa, Lasiantheae, plant conservation, plant diversity, sect. Nudiflorae

Lasianthus sondangii Bao, Vuong & V.C.Nguyen.
A. A flowering and fruiting branch. B. Apical shoot showing young leaves and stipule. C. Inflorescence and infructescence. D. Infructescence (side view) E. Flowers buds (mature (left) and immature (right)). F. Open flower in different views (side view (left) and top view (right)). G. Corolla artificially cut open, showing hairs at the throat and stamens. H. Flower with the corolla removed to show the ovary, calyx, style, and stigma (left) and longitudinal section that shows the calyx lobes, and the ovule (right). I. Mature fruit (left) and the cross section of fruit shows pyrenes and albumen of seeds (right).

Drawn by Phan Thi Thanh Nha from type QB137.

Lasianthus sondangii Bao, Vuong & V.C.Nguyen.
A. Habit and habitat. B. A flowering and fruiting branch. C. Apical shoot showing young leaves and stipule. D. Stipule. E. Leaves (adaxial surface (left) and abaxial surface (right)). F. Infructescence. G. Inflorescences. H. Inflorescence bearing open flowers.

(A, B, E–H by Nguyen Van Canh; C, D by Nguyen Quoc Bao from type QB137).

Lasianthus sondangii Bao, Vuong & V.C.Nguyen, sp. nov. 

Diagnosis: The new species is distinct from other Lasianthus species in Vietnam and Indo-China by its spiciform, sympodial, reduced-cymose inflorescence; purple flowers (including calyx), calyx lobes obovate with revolute margins.

Thi Thuy Nhan Tran, Van Canh Nguyen, Van Dung Luong, Thanh Nha Phan-Thi, Hoa Thi Nguyen, Ba Vuong Truong and Quoc Bao Nguyen. 2026. Lasianthus sondangii (Rubiaceae, Lasianthus section Nudiflorae), A New Species with a unique spiciform inflorescence from Central Vietnam. Taiwania. 71(3); 488 - 494. DOI: 10.6165/tai.2026.71.488 [26 May 2026] 

 https://taiwania.ntu.edu.tw/abstract/2193

[Botany • 2026] Ophiorrhiza bibracteata (Rubiaceae) • A New Species from Guangxi, China

Ophiorrhiza bibracteata Y.Nong & G.Y.Wei, 

in Nong, G.-Y. Wei, H.-Y. Wei, Long, Liu, Feng et Qin, 2026.

金钟山蛇根草  ||  DOI: doi.org/10.3897/phytokeys.275.189773

Abstract

Ophiorrhiza bibracteata (Rubiaceae), a new species from northwest Guangxi, China, is described and illustrated. It can be distinguished from its allies O. mitchelloides, O. nanlingensis and O. grandibracteolata by the shape and size of the bracts (ovate, 8–11 mm long) and the shape and size of the calyx lobes (triangular, 0.8–1.0 mm long, glabrous, with glands between the lobes). According to the IUCN Red List Categories and Criteria, the new species is assessed as Data Deficient (DD) until more information becomes available.

Key words: Morphology, new species, Ophiorrhiza, taxonomy

Ophiorrhiza bibracteata Y.Nong & G.Y.Wei.
A, B. Habit; C, D. Flowering plant; E. Brevistylous flower (front view); F. Flower (lateral view); G. Dissected brevistylous flower; H. Dissected longistylous flower; I. Ovary, calyx, style and stigma of longistylous (left) and brevistylous (right) flower; J. Ovary, calyx, style and stigma of brevistylous flower; K. Stipule; L. Bracts and flower bud; M. Leaf, adaxial surface; N. Leaf, abaxial surface; O. Fruiting plant; P. Capsules and bracts (images captured with a Nikon D850 camera).

Ophiorrhiza bibracteata Y.Nong & G.Y.Wei, sp. nov. 

Diagnosis. Ophiorrhiza bibracteata is similar to O. mitchelloides (Masam.) H.S.Lo, but differs in the following characters: the number of secondary veins (5–7 pairs in O. bibracteata vs. 3–5 pairs), the shape and size of the bracts (ovate, 8–11 mm long vs. linear, 4–8 mm long), the shape and size of the calyx lobes (triangular, 0.8–1.0 mm long, glabrous, with glands between the lobes vs. linear, ca 1.4 mm long, glabrescent or ciliate, without glands) and the nature of the flowers (distylous vs. monostylous).

Etymology. The specific epithet is derived from the Latin, bibracteata, meaning “two bracts” and referring to the two persistent ovate bracts of the new species.

Chinese name. 金钟山蛇根草 (jīn zhōng shān shé gēn căo).

 You Nong, Gui-Yuan Wei, Hai-Yong Wei, Lie Long, Zhi-Rong Liu, Bin Feng and Ting Qin. 2026. Ophiorrhiza bibracteata (Rubiaceae), A New Species from Guangxi, China.  PhytoKeys. 275: 151-161. DOI: doi.org/10.3897/phytokeys.275.189773 [29 May 2026]

[Botany • 2026] Firmiana laotica (Malvaceae) • A New Species from Limestone Karst, Khammouane Province, central Laos and Five New Records for the Flora of Laos

 

Firmiana laotica Sengthong, Soulad. & Tagane,

in Sengthong, Tagane, Souladeth, Dang, Yamamoto, Souvannakhoummane, Kongxaisavath, Phengmala, Tanaka et Pham, 2026.

DOI: doi.org/10.18942/apg.202523 

facebook.com/PhetlasySouladeth

 

Abstract

A new species, Firmiana laotica (Malvaceae), and five new records, Justicia oreophila (Acanthaceae), Aganosma wallichii (Apocynaceae), Colebrookea oppositifolia (Lamiaceae), Myristica yunnanensis (Myristicaceae), and Brachytome hainanensis (Rubiaceae) are reported for the flora of Laos. Voucher specimens, photographs, and ecological information in Laos are provided for each species.

Keywords: Central Laos, Firmiana laotica, flowering plants, Nam Kading NPA, Phou Hin Poun NP

Firmiana laotica Sengthong, Soulad. & Tagane.
A, habitat. B & C, habit. D, leafy twig. E, lower leaf surface. F, inflorescence. G, staminate flower. H & I, pistillate flowers. J, young fruits. All photos by Shuichiro Tagane.

Firmiana laotica Sengthong, Soulad. & Tagane, sp. nov. 

ປໍຜາລາວ

  Firmiana laotica is similar to F. fulgens (Wall. ex Mast.) K.Schum., but distinguished by leaf lobe apex (long-acuminate to caudate in F. laotica vs. acute to obtuse F. fulgens), lower leaf surface color (glaucous vs. not glaucous), depth of calyx lobes (lobed (1/3−)1/2 of calyx length vs. lobed 1/3–1/4 of calyx length), and number of stamens (15 in 5 groups of 3 vs. 20 or 25 in 5 groups of 4 or 5).

 

 Anousone Sengthong, Shuichiro Tagane, Phetlasy Souladeth, Van-Son Dang, Takenori Yamamoto, Keooudone Souvannakhoummane, Deuanta Kongxaisavath, Kajonesuk Phengmala, Nobuyuki Tanaka and Quoc Trong Pham. 2026. A New Species and Five New Records for the Flora of Laos. Acta Phytotaxonomica et Geobotanica. 77(1); 23-34. DOI: doi.org/10.18942/apg.202523 

 

ຂໍແນະນຳພືດຊະນິດໃໝ່ຂອງໂລກ ຈາກນິເວດພູຫິນປູນ (ບ້ານກອງລໍ ເຂດປ່າປ້ອງກັນພູໄຮ ແລະ The Rock at Phuphamarn ເມືອງຄູນຄຳ ແຂວງຄຳມ່ວນ)

ມີຊື່ວິທະຍາສາດ Firmiana laotica Sengthong, Soulad. & Tagane

ແລະ ໄດ້ໃຫ້ຊື່ລາວວ່າ ປໍຜາລາວ

  facebook.com/PhetlasySouladeth/posts/26072250059069501

[Botany • 2026] Ophiorrhiza jomyi (Rubiaceae) • A New Species from the Vagamon Hills, southern Western Ghats, India

 

Ophiorrhiza jomyi Ebin, Sreehari & Joby,  

in Ebin, Sreehari et Joby, 2026. 

DOI: doi.org/10.1002/njb.05085 

Abstract

A new species of Ophiorrhiza (Rubiaceae)is identified and described from the Vagamon hills of Kerala, Western Ghats, India. The new species is similar to Ophiorrhiza eriantha Wight and Ophiorrhiza meenachilarensis Robi and Balan, but differs in having densely hirsute hairs on young stem, petiole and peduncle; patent hirsute hairs on, above and beneath the leaf; 14.0–15.0 mm long flower; linear to falcate bracts and bracteoles; sparsely hirsute cupuliform hypanthium; triangular calyx lobes; 9.5–12.0 mm long corolla tube; stamens inserted at the middle of the corolla tube; and oblong and papillate stigma. A detailed description, colour photographs, comparison, phenology, distribution, conservation status and key to the allied taxa of the new species are provided.

Keywords: Kottayam, new species, Ophiorrhiza jomyi, Western Ghats

Ophiorrhiza jomyi Ebin, Sreehari & Joby sp. nov.
 (A) Habit, (B) stipule, (C–D) inflorescence, (E) bract, (F) bracteole, (G–H) adaxial and abaxial side of leaf, (I) indumentum on the upper surface of lamina, (J) indumentum on the lower surface of lamina, (K) flower bud, (L) single flower, (M) flower L.S., (N) indumentum on the stem, (O) indumentum on the peduncle, (O) indumentum on the petiole, (Q) hypanthium cup, (R) stamen, (S) gynoecium, (T) fruit, (U) seed.

Ophiorrhiza jomyi Ebin, Sreehari & Joby sp. nov.  

Diagnosis: This species shows close morphological resemblance with O. eriantha Wight, but differs in having densely ascending hirsute indumentum on stem (versus pubescent or glabrous stem), patent hirsute hairs on both sides of leaves (versus glabrous above, puberulous on the nerves beneath), densely hirsute petiole (versus glabrous or puberulous petiole), stipule acuminate to attenuate at apex (versus stipule bifid at apex), 14.0–15.0 mm long flower (versus 19.0–27.0 mm long flower), cupuliform hypanthium (versus obovoid hypanthium), triangular calyx lobes (versus subulate calyx lobes), densely puberulous hairs and with a villose ring at the middle of the corolla tube inside (versus glabrous inside without a ring of villose hairs), 2.5–3.0 mm long corolla lobes (versus 5.0–7.0 mm long corolla lobes), 1.75–2.0 mm long anthers (versus 3.0–3.5 mm long anthers), oblong stigma, obtuse at apex with papillate hairs (versus lanceolate stigma, acute at apex and glabrous), 0.4 × 0.5 mm, irregularly angled seeds (versus 0.6 × 0.5 mm, 4–6 angular seeds).

Etymology: The specific epithet is in honour of retired Professor, Dr Jomy Augustine, Department of Botany, St Thomas College, Pala, Kottayam, Kerala, for his guidance and support in the field of taxonomy to the authors. Dr Jomy Augustine has significantly contributed to the documentation and conservation of plant diversity in the Western Ghats through his extensive field explorations, research and publications.

 

Ebin Padiyara Joy, Sreehari Sivan Nair, Joby Paul. 2026. Ophiorrhiza jomyi (Rubiaceae) sp. nov. from the Vagamon Hills, southern Western Ghats, India. Nordic Journal of Botany. DOI: doi.org/10.1002/njb.05085 [21 March 2026]

 

[Botany • 2025] Keetia magassoubiana (Rubiaceae: Vanguerieae) • A threatened evergreen forest Climber and an updated key to Keetia in West Africa

Keetia magassoubiana Cheek, 

 

in Cheek, Yasuda, Jongkind et Bowden-Pickstock, 2025.

DOI: doi.org/10.1007/s12225-024-10234-z

Summary

Keetia magassoubiana Cheek, an evergreen rainforest climber, is described and illustrated from the Republic of Guinea, Sierra Leone, Liberia and Ivory Coast. Previously indicated as being close to, but different from, K. tenuiflora (Hiern) Bridson, it differs in the glossy, black, glabrous, epidermis of the distal stem internodes; the first internode rarely with very sparse, red adpressed hairs (vs epidermis pale white-brown, with dense, pale yellow, spreading hairs); abaxial leaf surfaces with domed domatia with a central aperture (vs domatia absent or obscure); secondary stem leaf bases acute (vs obtuse to truncate); bracts forming a laciniate sheath on the distal peduncle (vs two opposite triangular bracts) and the pyrene surface honeycombed with pits (vs entire). The species was earlier included within Canthium multiflorum (Schum. & Thonn.) Hiern, now K. multiflora (Schum. & Thonn.) Bridson, in the Flora of West Tropical Africa, second edition. An updated key is presented to the 16 species of the genus from West Africa. Keetia magassoubiana is provisionally assessed using the IUCN standard as Endangered [EN B1ab(iii)] due to only five of the recorded 14 locations having extant forest habitat, and because of ongoing threats of habitat clearance, mainly for agriculture but also for mining.

Key Words: Conservation, extinction, liana

Keetia magassoubiana Cheek sp. nov.

Recognition. Keetia magassoubiana Cheek sp. nov. is close to but differs from K. tenuiflora in the glossy, black, glabrous epidermis of the distal stem internodes, rarely with very sparse red hairs (vs epidermis pale white-brown, densely pale yellow hairy in K. tenuiflora), abaxial leaf surface with domatia domed, with a central aperture (vs domatia absent or obscure), the secondary stem leaf bases acute (vs obtuse to truncate), the bracts forming a laciniate sheath on the distal peduncle (vs two opposite triangular bracts) and the pyrene surface honeycombed with pits (vs smooth).

Etymology. Named for Dr Sekou Magassouba, Director-General of the National Herbarium of Guinea (HNG) in the University of Gamal Abdel Nasser – Conakry, Republic of Guinea. Under his careful, tireless and diligent administration, HNG has increased greatly in its capacity to devise and manage projects, attract grants, to train students, including now at doctorate level for the first time and to develop publication of research and publicise the conservation of the threatened plant species and habitats of his country.

Martin Cheek, Shigeo Yasuda, Carel C. H. Jongkind and Joel Bowden-Pickstock. 2025. Keetia magassoubiana sp. nov. (Rubiaceae - Vanguerieae), a threatened evergreen forest climber and an updated key to Keetia in West Africa. Kew Bulletin. DOI: doi.org/10.1007/s12225-024-10234-z

[Botany • 2025] Tarenna khoonmengiana (Rubiaceae) • A New Species from Peninsular Malaysia and Peninsular Thailand

Tarenna khoonmengiana Junhao Chen & Y.H.Cheah,

in Chen et Cheah, 2025. 

 Sandakania. 27; 

A new species, Tarenna khoonmengiana (Rubiaceae), from Peninsular Malaysia and Peninsular Thailand is described and illustrated here. Notes on the ecology, etymology and morphological distinctions from similar species are provided here.

Tarenna khoonmengiana Junhao Chen & Y.H.Cheah, sp. nov.

Similar to Tarenna stellulata (Hook.f.) Ridl. and Tarenna insularis (Ridl.) Ridl. in having corolla lobe tips that are divergent in the bud, but differing from the former in the glabrous lower leaf lamina surface that is smooth to the touch (vs minute erect hairy lower leaf lamina surface that is rough to the touch), glabrous (vs conspicuously ciliate) corolla lobe margins and acute (vs awl-like) corolla lobe apex, and differing from the latter in the broadly triangular (vs linear) calyx lobes 0.5–1 mm long (vs 1.5–3 mm long) and glabrous (vs densely short-puberulent) corolla outer surface in bud.

Junhao Chen & Y.H. Cheah. 2025. Tarenna khoonmengiana (Rubiaceae), A New Species from Peninsular Malaysia and Peninsular Thailand. Sandakania. 27; 49-58. 

 

[Botany • 2025] Psychotria caraballoensis (Rubiaceae) • A New Species from northern Luzon, Philippines

Psychotria caraballoensis Pajarillaga, Ordas & Moran, 

in Pajarillaga, Ordas, Odulio, Venturina et Moran, 2025. 

DOI: doi.org/10.1002/njb.05026

Abstract

In this paper, we describe and illustrate Psychotria caraballoensis, a new endemic species from the Caraballo Mountain Range, Luzon, Philippines. It is allied to the Subalpina species group sensu Sohmer and Davis (2007), and resembles Psychotria sohotonensis. However, it is distinct by its greater number of lateral veins, leaf blades drying khaki to dark brown, inflorescences/infructescences with axes branching into verticillate or oppositely branched cymules, puberulous flowers with longer corolla lobes, smaller and globose to subglobose fruits, and ruminate endosperms. It is one of few species of Philippine Psychotria documented to have both long and short-styled flower morphs. The conservation status of this species is proposed as ‘Endangered' (EN), due to its restricted range and the presence of anthropogenic threats in the area.

Keywords: distylous, montane, Nueva Vizcaya, Philippine flora, Psychotrieae, taxonomy

Psychotria caraballoensis sp. nov. 
(A) Flowering individual, (B) stipules and leaf attachment, (C) short styled flower, (D) short styled flower front view, (E) corolla, (F) opened corolla, (G) calyx and hypanthium of short styled flower, (H) infructescence, (I) fruit, (J) fruit cross-section showing pyrenes, (K) pyrenes (left – dorsal view, right -ventral view).

Scale bars – A = 1 cm, B–K = 1 mm. Illustrated by Propa Joy S. Venturina.

Psychotria caraballoensis sp. nov.
(A) Leaf attachment and stipules, (B) leaves with abaxial side (top) and adaxial side (below), (C) inflorescence, (D) long-styled flower (pin), (E) short-styled flower (thrum), (F) infructescence, (G) fruits.

Scale bar A–C = 1 cm, D–G = 5 mm. 

Photographs A and C–F by Lyle Christian P. Santiago and B and G by Sarah Grace S. Zamudio.

Psychotria caraballoensis Pajarillaga, Ordas & Moran sp. nov.  

Diagnosis: A species closely resembling Psychotria sohotonensis Sohmer and Davis, but distinct by its leaf blades with numerous lateral veins (14–19 versus 10–14) drying khaki to dark brown (versus dark brown to dark olivaceous brown), inflorescences/infructescences with axes that further branch into verticillate or oppositely branched cymules (versus axes terminating into shortly branched cymules), puberulous flowers (versus glabrous) with longer corolla lobes (2.7–3.2 mm versus 1.5 mm), smaller (4.0–5.5 mm versus 8–9 mm) globose to subglobose fruits (versus ellipsoid-globose), and ruminate endosperms (versus entire). Additionally, dimorphic flower morphs with long and short styles were observed.

Etymology: This species was named after the Caraballo Mountain Range of Nueva Vizcaya Province, where it was discovered.

 

Jenifer D. Pajarillaga, Jorge Anton D. Ordas, Eiana Joshier A. Odulio, Propa Joy S. Venturina and Cecilia B. Moran. 2025. Psychotria caraballoensis (Rubiaceae), A New Species from northern Luzon, Philippines. Nordic Journal of Botany. DOI: doi.org/10.1002/njb.05026  [14 November 2025]

[Botany • 2025] Argostemma sawmlianae (Rubiaceae: Argostemmateae) • A New Species from Northeast India under the Indo-Burma Hotspot

 

Argostemma sawmlianae Lalhlupuii, Tlanhlui, S.D.Khomdram & S.D.Yumkham, 

in Lalhlupuii, Tlanhlui, Khomdram et Yumkham. 2025. 

DOI: doi.org/10.3897/phytokeys.266.162537

Abstract

Argostemma sawmlianae (Rubiaceae), a new species from Mizoram, Northeast India, within the Indo-Burma hotspot, is described and illustrated. The species is compared with its allied species A. courtallense and A. sarmentosum, from which it differs by a set of distinctive morphological characters that include a pair of larger sessile leaves (11.5–18.5 cm long), longer peduncle (4–6.5 cm long), more flowers per cyme (8–33) and campanulate corolla with falcate lobes, reflexed and prominently rolled backward. The molecular analyses based on matK (cpDNA) and ITS2 (nrDNA) sequences support the morphological evidences confirming A. sawmlianae as a distinct new species. The newly discovered species is provisionally categorized as Critically Endangered (CR) in accordance with the IUCN Red List Categories and Criteria (IUCN 2024) based on available data.

Key words: Argostemma, Indo-Burma hotspot, Mizoram, molecular, morphology, new species

Argostemma sawmlianae Lalhlupuii, Tlanhlui, S.D.Khomdram & S.D.Yumkham, sp. nov.
 A, B. Habit; C. Anisophyllous leaves with inflorescence (inverted view); D. Leaf with stipule; E, F. Anisophyllous leaves; G. Flower with bract; H. Inflorescence; I. Foliaceous bracts; J. Rudimentary leaves; K. Petaloid calyx with green tips; L. Corolla with green blotched tubes; M. Corolla with reflexed and backwardly rolled lobes; N. Single falcate shaped corolla lobe; O. Corolla lobes; P. Single stamen with curved filament; Q. Androecium with loosely arranged stamens.

 (photos by Margaret Lalhlupuii & Lal Tlanhlui).  

Argostemma sawmlianae Lalhlupuii, Tlanhlui, S.D.Khomdram & S.D.Yumkham, sp. nov.
A. Single flower; B. Pistil; C. Cross section of ovary; D. Seeds (LM image); E. Seed (SEM image); F. Pollen (SEM image); G. A. sawmlianae in type locality;
H, I. A. verticillatum from Manipur; J. A. kamjongense from Manipur; K. A. sarmentosum from Meghalaya. (photos by Margaret Lalhlupuii, Lal Tlanhlui & Yumkham).

 Argostemma sawmlianae Lalhlupuii, Tlanhlui, S.D.Khomdram & S.D.Yumkham, sp. nov.

 

Diagnosis. It is similar to Argostemma courtallense Arn. and A. sarmentosum Wall., but differs from the two in having one pair of larger sessile leaves (11.5–18.5 cm long), longer peduncle (4–6.5 cm long), more flowers per cyme (8–33), and campanulate corolla with falcate petals which are reflexed and strongly rolled backwards (Fig. 3, Table 1).

...

 Margaret Lalhlupuii, Lal Tlanhlui, Sandhyarani Devi Khomdram, Sanatombi Devi Yumkham. 2025. Argostemma sawmlianae (Rubiaceae, Argostemmateae), A New Species from Northeast India under the Indo-Burma Hotspot. PhytoKeys. 266: 317-328. DOI: doi.org/10.3897/phytokeys.266.162537

[Botany • 2025] Argostemma wardii (Rubiaceae) • A New Species from Ayeyarwady Region, Myanmar

 

Argostemma wardii Y.H.Tan & D.L.Quan,

in Quan, Xie, Yang, Swe, Htwe et Tan, 2025. 

 DOI: doi.org/10.11646/phytotaxa.718.3.8  

  Researchgate.net/publication/396406068

Abstract

Argostemma wardii Y.H.Tan & D.L.Quan, a new species of Rubiaceae is described and illustrated from Ayeyarwady Region, southern Myanmar. This species is closely similar to A. kurzii but can be distinguished by its typically having 2-paired leaves that are thinly papery and spatulate, lanceolate, or elliptic in shape, with bases that are attenuate, cuneate, or asymmetrical. Additionally, A. wardii has larger stipules (5–15 × 10–30 mm vs. 1 × 2–5 mm), fewer inflorescences (1 or rarely 2 vs. 1–4), shorter peduncles (1.5–6.5 cm vs. 4–12 cm), a fleshy calyx (vs. chartaceous), subtle corolla venation (vs. conspicuous), and larger bracts (2–7 × 5–12.5 mm vs. 2–3.5 × 3–5 mm) and corollas (2 × 4–4.5 mm vs. 1.5 × 2–2.5 mm), along with longer corolla tubes (0.5–1 mm vs. 0.4–0.6 mm) and anthers (2–2.5 mm vs. 1 mm).

Argostemmateae, coffee family, flora, plant taxonomy, Southeast Asia, Eudicots 

Argostemma wardii Y.H.Tan & D.L.Quan,

Dong-Li QUAN, Xing-Chi XIE, Bin YANG, Yadanar SWE, Kaung Myat HTWE and Yun-Hong TAN. 2025. Argostemma wardii (Rubiaceae), A New Species from Ayeyarwady Region, Myanmar.  Phytotaxa. 718(3); 244-248. DOI: doi.org/10.11646/phytotaxa.718.3.8 [2025-09-23]

 Researchgate.net/publication/396406068_Argostemma_wardii_a_new_species_from_Ayeyarwady_Region_Myanmar

http://english.xtbg.cas.cn/rh/rp/202510/t20251011_1089280.html

[Botany • 2025] Ophiorrhiza mizoramensis (Rubiaceae) • A New Species From Mizoram, India

 

Ophiorrhiza mizoramensis  R. Lalnunfeli & L. Lalawmpuii, 

in Lalnunfeli, Lalawmpuii, Yadav, Karuppusamy et Richard. 2025.  

DOI: doi.org/10.1002/fedr.70036 

 Researchgate.net/publication/396927525

 

ABSTRACT

A new species, Ophiorrhiza mizoramensis, is described from Murlen National Park, Mizoram, India. This species is closely allied to O. gajureliana Bawri & Baro, O. ripicola Craib and O. ochroleuca Hook.f., but can be differentiated by several characters, including 10–19 pairs of lateral leaf veins, a petiole up to 6 cm long; persistent ovate stipule; a pubescent, peduncled biparous helicoid cyme inflorescence reaching up to 12 cm in length; dark purplish-pink corolla tube up to 1.8 cm long; and oblanceolate stigma lobes about 14 mm in length. To enhance the understanding of this newly described species, comprehensive documentation has been provided, which includes a detailed morphological description, phenology, distribution, ecology, conservation status, comparative analysis of morphological features with closely allied species along with illustration and color photographs. The new species is evaluated and provisionally assessed as “Critically Endangered (CR-D)” according to recent red list IUCN criteria.

Keywords: India, new taxon, Ophiorrhiza, Rubiaceae, taxonomy

Ophiorrhiza mizoramensis R. Lalnunfeli & L. Lalawmpuii sp. nov.

 

Renthlei Lalnunfeli, Lucy Lalawmpuii, Pochamoni Bharath Simha Yadav, Subbiah Karuppusamy and Paulraj Selva Singh Richard. 2025. Ophiorrhiza mizoramensis (Rubiaceae)—A New Species From Mizoram, India. Feddes Repertorium. DOI: doi.org/10.1002/fedr.70036 [26 October 2025]

 Researchgate.net/publication/396927525_Ophiorrhiza_mizoramensis_A_New_Species_From_Mizoram_India

[Botany • 2024] Ophiorrhiza liuyanii (Rubiaceae) • A New Species from south-western China and northern Vietnam

Ophiorrhiza liuyanii L.Wu, Y.H.Tan & K.S.Nguyen,

in Liu, Liao, Ye, Tan, Nguyen, Thien et Wu, 2024. 

宽翅蛇根草  ||  DOI: doi.org/10.3897/phytokeys.248.135078 

Abstract

Ophiorrhiza liuyanii, a new species from south-western China and northern Vietnam, is described and illustrated. The new species is characterised by the glabrous surfaces on almost all plant parts, congested inflorescences and broad-ovate to ovate bracts 9–22 × 4–11 mm. It morphologically differs from the closest species, O. baviensis, mainly in most plant parts being glabrous, bracts broad-ovate to ovate, apex acute or sometimes obtuse, corollas inside with a ring of white hairs at the middle and anthers inserted near the middle in long-styled flowers. According to IUCN Categories and Criteria, O. liuyanii is assessed as Least Concern (LC).

Key words: New taxon, Ophiorrhiza, Rubiaceae, taxonomy

Ophiorrhiza liuyanii A habitat B habit C stipule D inflorescence in side view E inflorescences in different development stages F bracts from lower part to upper part of inflorescence G corollas in top view H longitudinally dissected long-styled flower I longitudinally dissected short-styled flower J infructescence in side view K infructescence in top view.
Ophiorrhiza alatiflora L habit M inflorescence in lateral view N infructescence.

Scale bars: 1 cm. Photos by L. Wu, X. W. Liao and K. S. Nguyen.

 Ophiorrhiza liuyanii L.Wu, Y.H.Tan & K.S.Nguyen, sp. nov.

 

Diagnosis: Morphologically similar to O. alatiflora and O. baviensis, but the new species differs from the former by its congested (vs. developing) inflorescences and infructescences, broad-ovate to ovate (vs. linear or linear-lanceolate) bracts, 4–11 (vs. 0.8–1.5) mm wide and from the latter by its glabrous (vs. densely pubescent or puberulent) peduncles, broad-ovate to ovate (vs. lanceolate) bracts, corollas tube inside with (vs. without) a ring of white hairs at the middle in long-styled flowers.

Etymology: The species epithet is named after Prof. Yan Liu, Guangxi Institute of Botany, Guangxi Zhuangzu Autonomous Region and the Chinese Academy of Sciences, who has made great contributions to plant taxonomy in China.

Chinese name: 宽翅蛇根草 (kuan-chi-she-gen-cao).

 Chu-Yu Liu, Xiao-Wen Liao, Li-Chun Ye, Yun-Hong Tan, Khang Sinh Nguyen, Tran Duc Thien and Lei Wu. 2024. 2024. Ophiorrhiza liuyanii (Rubiaceae), A New Species from south-western China and northern Vietnam. PhytoKeys. 248: 199-206. DOI: doi.org/10.3897/phytokeys.248.135078 

[Botany • 2025] Tarenna pendula (Rubiaceae: Ixoroideae) • A New Species from Guangxi, China

 

Tarenna pendula  Y.H.Qin, S.X.Yu & W.H.Wu, 

in Qin, Bussmann, Liu, Li, Xia, Wu et Yu, 2025.

 DOI: doi.org/10.3897/phytokeys.257.148816 

Abstract

The species Tarenna pendula (Rubiaceae), a small shrub, is newly described and illustrated from southwestern Guangxi Autonomous Region, China. This species is similar to Tarenna tsangii but is readily distinguished by its asymmetrical leaves, larger vegetative leaves than inflorescence leaves, adaxially pilosulous blades, pendulous inflorescences, longer pedicels (15–35 mm vs. 4–7 mm in T. tsangii), shorter corolla tubes (1–1.4 cm vs. 1.8–1.9 cm), multiple ovules per locule (vs. two), and sparsely pubescent fruits containing 13–19 seeds (vs. glabrous fruit containing only four seeds).

Key words: Distribution, Ixoroideae, morphology, Pavetteae, taxonomy

Tarenna pendula sp. nov.
A flowering branches B portion of inflorescence showing stipule C portion of stem showing stipule D portions of adaxial and abaxial leaf surfaces, (D1) pressure side of blade, (D2) low pressure side of blade E flower F stamen G longitudinally opened corolla showing the position of the stamens H pedicel, bracteoles, ovary and calyx I ovary, calyx, style and stigma J fruit K cross section of ovary L longitudinal section of fruit.

Drawings by Lijie Zhu, based on type specimens.

Tarenna pendula sp. nov. 
 A habitat B flowering branch C pendulous cyme D flower (D1) and ovary and calyx (D2) E longitudinally opened corolla F ovary, calyx, style and stigma G fruiting branch H blade in adaxial view (H1) and in abaxial view (H2) I young fruits in different developmental stages J unripe seeds clustered together (after removal of fruit wall) K unripe seeds.

 Tarenna pendula Y.H.Qin, S.X.Yu & W.H.Wu, sp. nov.

 

Diagnosis. Similar to Tarenna tsangii, but distinguished by its small form, asymmetrical leaves, vegetative leaves larger than inflorescence leaves, blades adaxially pilosulous, pendulous inflorescences, longer pedicels (15–35 mm vs. 4–7 mm in T. tsangii), shorter corolla tubes (1–1.4 cm vs. 1.8–1.9 cm), multiple ovules per locule (vs. 2), and sparsely pubescent fruits with 13–19 seeds (vs. glabrous fruit containing only 4 seeds).

Etymology. The specific epithet is derived from the pendulous inflorescence, which differs from several other Tarenna spp. in the area.

Vernacular name. Chuixiu wukoushu in Mandarin Chinese, 

which translates to ‘pendulous Tarenna’.

 Yong-Hua Qin, Rainer W. Bussmann, Zhi-Rong Liu, Man Li, Chang-Ying Xia, Wang-Hui Wu and Sheng-Xiang Yu. 2025. Tarenna pendula (Rubiaceae), A New Species from Guangxi, China. PhytoKeys. 257: 1-8. DOI: doi.org/10.3897/phytokeys.257.148816 

 

[Botany • 2022] Ceriscoides glabra (Rubiaceae: Gardenieae) • A New Species from Kon Chu Rang Nature Reserve, southern Vietnam

 

Ceriscoides glabra B.H.Quang, N.T.Cuong, T.D.Binh & Nuraliev, 

in Binh, Quang, Cuong, Quynh, Hoan, Hai, Nguyen et Nuraliev. 2022.

 Kon Chu Rang 

 DOI: 10.11646/phytotaxa.574.2.4 

 

Abstract

Ceriscoides glabra, a new species of the tribe Gardenieae (Rubiaceae), is described and illustrated. The species was discovered in 2017–2018 in Kon Chu Rang Nature Reserve (Gia Lai Province, southern Vietnam), in the vicinity of the locally well-known K50 waterfall, also known as Hang En waterfall. The new species differs from its congeners by the following features: plant entirely glabrous, leaf blade mostly less than 6.5 cm long and less than 4 cm wide, with 3–4 pairs of secondary veins and without domatia, calyx in female flowers glabrous with lobes more than 9 mm long, and corolla lobes in female flowers more than 10 mm long and distinctly longer than wide.

Keywords: brachyblasts, Eastern Indochina, floral dimorphism, Gia Lai Province, plant diversity, plant taxonomy, thorns, Eudicots 

  

Ceriscoides glabra

Tran Duc Binh, Bui Hong Quang, Nguyen The Cuong, Ha Quy Quynh, Duong Thi Hoan, Do Van Hai, Khang Sinh Nguyen and Maxim S. Nuraliev. 2022. Ceriscoides glabra (Gardenieae: Rubiaceae), A New Species from Kon Chu Rang Nature Reserve, southern Vietnam. Phytotaxa. 574(2); 158-164. DOI: 10.11646/phytotaxa.574.2.4 

  twitter.com/DiepDinh8/status/1597716551964061696