[Botany • 2026] Hydrangea medogensis (Hydrangeaceae) • A New Species from Xizang (Tibet), China

 

Hydrangea medogensis X.Z.Lan, W.L.Zheng & W.Q.He, 

in He, Zheng, F.-Y. Zhao, Yin, Li, K.-H. Zhao, Zhang, Liao et Lan, 2026.

墨脱绣球  |  DOI: doi.org/10.3897/phytokeys.279.203326 

Abstract

Based on field surveys, examination of herbarium specimens, and molecular phylogenetic analyses, the present study described a new species, Hydrangea medogensis sp. nov. (Hydrangeaceae), from Medog County, Xizang Autonomous Region, China. Phylogenetic analyses indicated that H. medogensis was placed in Clade 1 as a distinct lineage, sister to the remainder of the clade. Morphologically, the new species is most similar to H. stylosa but can be distinguished by the following key characteristics: fertile flowers with a globose calyx tube constricted at the mouth; calyx teeth triangular, occasionally oblong-ovate, 0.6–1 mm long; adaxial leaf surface covered with two types of soft hairs (long and short); ovary more than 4/5 inferior, nearly completely inferior; and seeds with a very narrow wing around the margin. The taxonomic status of the new species was established based on integrated morphological and molecular evidence.

Key words: Hydrangea, morphological analysis, new species, phylogenetic analysis

Hydrangea medogensis X.Z.Lan, W.L.Zheng & W.Q.He.
A. Habit; B. Fruiting branch; C. Adaxial surface of leaf; D. Abaxial surface of leaf; E. Flower bud; F. Flower; G. Fruit; H. Seed (drawing by Wenqi He).

Hydrangea medogensis X.Z.Lan, W.L.Zheng & W.Q.He. 
A. Habitat; B. Flowering branch; C. Sterile flowers and young fruits; D. Branchlet; E. Fruiting branch.

Hydrangea medogensis X.Z.Lan, W.L.Zheng & W.Q.He, sp. nov.

Diagnosis. Hydrangea medogensis is morphologically similar to H. stylosa, but differs in having ovaries more than 4/5 inferior (vs. ca. 2/3 inferior), leaves with adaxial surface covered with long and short hairs (vs. nearly glabrous or glabrous on both surfaces), fertile flowers with calyx tube subglobose, calyx opening constricted, calyx teeth triangular, occasionally oblong-ovate, 0.6–1 mm long (vs. calyx tube campanulate, calyx opening tubular, calyx teeth ovate or suboblong, 1–1.5 mm long), and seeds narrowly winged around margin (vs. minutely winged at one or both ends).

Etymology. The epithet indicates the type locality, i.e., Medog area, Xizang, China.

Vernacular name. mò tuō xiù qiú (Chinese pronunciation); 

墨脱绣球 (Chinese name).

 Wen-Qi He, Wei-Lie Zheng, Fang-Yu Zhao, Kai-Xin Yin, Lian-Qiang Li, Kai-Hui Zhao, Fang-yuan Zhang, Zhi-hua Liao and Xiao-Zhong Lan. 2026. Hydrangea medogensis (Hydrangeaceae), A New Species from Xizang (Tibet), China. PhytoKeys. 279: 51-68. DOI: doi.org/10.3897/phytokeys.279.203326 [10 Sep 2026]

[Botany • 2026] Didiclis pseudobisulcata (Selaginellaceae) • A New Species of the Bisulcata group from northern Thailand and southwest China

  

Didiclis pseudobisulcata  X.M.Zhou & Liang Zhang,

in Gong, Hu, Pollawatn, Chantanaorrapint, Wang, Zhang et Zhou. 2026. 

 DOI: doi.org/10.3897/phytokeys.278.204624

Abstract

Didiclis pseudobisulcata (Lycopodioidoideae, Selaginellaceae), a new lycophyte species from northern Thailand and southwest China, is described and illustrated. Morphologically, it is similar to D. bisulcata but can be reliably distinguished by its dorsal leaves on branches with an arista often more than 3/4 of the leaf length, the densely ciliolate base of the dorsal sporophyll pteryx, and megaspores with subreticulate exospore ornamentation. Molecular phylogenetic analysis based on ITS and rbcL sequences supports this species as an independent clade. The ITS sequences revealed more than 42 nucleotide differences between the new species and other members of the Bisulcata group, providing clear molecular evidence for its separation from its closest relatives.

Key words: Asia, Lycopodioidoideae, megaspore and microspore, phylogeny

Field photographs of Didiclis pseudobisulcata.
 A, B. Plant in its natural habitat; C. Dorsal view of stems and branches with strobili; D. Ventral view of stems and branches with strobili; E. Dorsal view of strobilus; F. Ventral view of strobilus; G. Dorsal view of a portion of the main stem, showing ventral and dorsal leaves; H. Dorsal view of a portion of a branch, showing ventral and dorsal leaves; I. Ventral view of a portion of the main stem, showing axillary and ventral leaves; J. Ventral view of a portion of a branch, showing axillary and ventral leaves.

(from voucher: Liang Zhang, Xin-Mao Zhou, Lu-Yao Jiang, & Xu-Ke Han 5734).

Didiclis pseudobisulcata X.M.Zhou & Liang Zhang, sp. nov.

 Sheng-Rong Gong, Yu-Ping Hu, Rossarin Pollawatn, Sahut Chantanaorrapint, Wen Wang, Liang Zhang and Xin-Mao Zhou. 2026. Didiclis pseudobisulcata (Selaginellaceae), A New Species of the Bisulcata group from northern Thailand and southwest China. PhytoKeys. 278: 233-246. DOI: doi.org/10.3897/phytokeys.278.204624

[Botany • 2026] Primula pingwuensis (Primulaceae) • A New Species in Primula sect. Auganthus from Sichuan, China

Primula pingwuensis Y.Hu, J.L.Gu & S.Y.Zhang,  

in Zhang, Fang, Y.-F. Hu, Y. Hu, Gu, Wu et Shao, 2026. 

Primula (China.  . 278: 247-258.

平武报春  | DOI: doi.org/10.3897/phytokeys.278.204611

Abstract

Primula pingwuensis sp. nov., a new species of Primula sect. Auganthus from Sichuan, China, is described. It resembles P. sinensis in having palmately lobed leaves and multi-whorled inflorescences but differs by its multi-branched stems, more densely short-pubescent surfaces, thicker chartaceous leaves, narrower leaf blades, and indistinct translucent nectar guides. A taxonomic key covering all nine known species of Primula sect. Auganthus is compiled herein to support field morphological discrimination. A chloroplast genome-based phylogeny shows that P. pingwuensis is sister to P. rongrong, and this clade is sister to P. fujiangensis. Incongruence between morphology and molecular phylogeny is observed within the section. Leaf-lobing patterns have undergone multiple independent evolutionary transitions during adaptive radiation in karst habitats, indicating that a few morphological traits cannot be used to reliably infer interspecific relationships. The new species is assessed as Data Deficient (DD) following IUCN criteria, owing to the lack of long-term observations of its threat status and population dynamics. This study provides new data for the taxonomy and evolution of Primula sect. Auganthus.

Key words: Phylogeny, Primula, sect. Auganthus, Sichuan, taxonomy

Primula pingwuensis sp. nov.
A, B. Habitat; C. Flowering plant in the wild;
Da. Flowering plant; Db. Root; Dc. Adaxial surface; Dd. Abaxial surface; De. Front view of pin flower; Df. Front view of thrum flower; Dg. Longitudinal section of thrum flower; Dh. Longitudinal section of pin flower; Di. Bract; Dj. Young fruits; Dk. Young fruit, showing ovary.

Primula pingwuensis Y.Hu, J.L.Gu & S.Y.Zhang, sp. nov.

Diagnosis. Primula pingwuensis is morphologically similar to P. sinensis in having palmately lobed leaves and multi-whorled scapes but differs by its multi-branched stems, densely pubescent indumentum, thickly chartaceous leaves (vs. submembranous in P. sinensis), narrower blades (3–6 cm wide), 2–3 flower whorls, and indistinct translucent ...

Etymology. The specific epithet is derived from Pingwu County, Mianyang City, Sichuan Province, the type locality of the new species, which is also an important habitat of the giant panda.

Chinese name. Píng Wŭ Bào Chūn (平武报春).

 Si-Yu Zhang, Ming Fang, Ying-Feng Hu, Yang Hu, Jiu-Lin Gu, Zhi-Kun Wu and Jian-Wen Shao. 2026. Primula pingwuensis (Primulaceae), A New Species in Primula sect. Auganthus from Sichuan, China. PhytoKeys. 278: 247-258. DOI: doi.org/10.3897/phytokeys.278.204611 [25 Aug 2026]

[Botany • 2026] Thismia daemona (Thismiaceae) • A New Species of Thismia sect. Geomitra from Thailand supported by morphological and molecular evidence

 

Thismia daemona Seelanan & Chantanaorr.,

in Seelanan, Chantapram, Taosiri, Chuchuea et Chantanaorrapint, 2026.

 DOI: doi.org/10.3897/phytokeys.278.202868

Abstract

A new species of Thismia from Thailand, Thismia daemona is described based on morphological characters and molecular phylogenetic analyses. Morphological characters were examined from fresh and spirit materials using a stereo microscope. Phylogenetic analyses were conducted based on three nuclear (SSU, ITS, LSU) and two mitochondrial (atpA, matR) markers. The new species is characterized by coralliform roots, blackish flowers, reddish orange and fleshy outer tepals, inner tepals forming a mitre with three slender claviform appendages, inner surface of floral tube possessing irregular transverse bars in lower half and finely reticulations in upper half, epidermis of transverse bars and reticulations covered with white translucent trichomes, and translucent blue stamens with recurved apex. Phylogenetic analyses support its placement within Thismia sect. Geomitra, with a sister relationship to T. betung-kerihunensis. In addition, the new species is assessed as Critically Endangered according to the IUCN Red List categories and criteria.

Key words: Achlorophyllous plants, conservation status, coralliform root, endemic species

Thismia daemona Seelanan & Chantanaorr.
A. Underground part showing hairy roots; B. Above-ground shoots with flowers; C. Top view of mitre showing irregular papillose surface; D. Side view of flower showing outer lobe; E. Longitudinal section of floral tube showing inner surface, three stamens, stylar column and styles; F. Epidermal cells of transversal bar; G. Stamens outer view. H. Stylar column and styles.

Photographed by N. Taosiri (B, C, E, G, H) and C. Chuchuea (A, D, F).

Locality and habitats of Thismia daemona Seelanan & Chantanaorr.
A. Distribution map; B–D. Habitats; arrowheads indicate plants of T. daemona; E. Plants in natural habitat. Photographed by C. Chuchuea (B–D) and N. Taosiri (E).

Thismia daemona Seelanan & Chantanaorr., sp. nov.

Diagnosis. Thismia daemona is somewhat similar morphologically to T. limkokthayi, but differs in having reddish orange and fleshy outer tepals, outer surface of mitre covered with irregular papillae, inner surface of floral tube possessing irregular transverse bars in lower half and finely reticulations in upper half, epidermis of transverse bars and reticulations covered with translucent white trichomes, translucent blue stamens, and absence of mitre foveae.

Habitat and ecology. Thismia daemona was found growing amongst leaf litter, under shade of lower montane forest with small bamboo, at elevations 950–970 m.

 Tosak Seelanan, Isareyakorn Chantapram, Neeranuch Taosiri, Chanachon Chuchuea and Sahut Chantanaorrapint. 2026. Thismia daemona (Thismiaceae), A New Species from Thailand supported by morphological and molecular evidence. PhytoKeys. 278: 177-189. DOI: doi.org/10.3897/phytokeys.278.202868 [17-08-2026]

[Botany • 2026] Primula exserta (Primulaceae) • A New Species in Primula sect. Aleuritia from Yunnan, China

 

Primula exserta Lei Cai, Gui L.Zhang & Z.K.Wu, 

in Yang, Zhang, Zheng, Ye, Tan, Cai et Wum 2026. 

大围山报春  ||  DOI: doi.org/10.3897/phytokeys.278.202553

Abstract

Primula exserta Lei Cai, Gui L. Zhang & Z. K. Wu, a new species of Primulaceae from Yunnan, China, is described and illustrated. Morphological evidence supports its placement within Primula sect. Aleuritia, a section characterized by entirely glabrous plants that lack scales at the base of the leaf rosette, has a moderate to small habit and typically bears farina on the foliage and scape. The new species differs from other members of this section by its petiole with broad wings, 7–8-lobed corolla and calyx, corresponding 7–8 stamens, and elongated filaments and a style exserted far beyond the mouth of the corolla tube. Information on its distribution, a morphological comparison with related species, and a preliminary assessment of its conservation status are also provided.

Key words: Conservation status, diversity, nomenclature, Primula, taxonomy, Yunnan

Primula exserta sp. nov.
A. Habitat; B. Habit during flowering; C. Lateral view of the plant; D. Leaves, left: upper surface, right: lower surface; E. Flower, frontal view; F. Flower, lateral view; G. Dissected corolla showing the anthers and stigmas; H. Dissected corolla with the ovary; I. Dissected calyx.  

Primula exserta sp. nov.
A. Flowering habit; B. Leaves, left: upper surface, right: lower surface; C. Flower, lateral view; D. Dissected corolla showing the anthers and stigmas; E. Dissected calyx.

Drawn by Ms. Yang-yang Zheng.

Primula exserta Lei Cai, Gui L.Zhang & Z.K.Wu, sp. nov.

 

Diagnosis. This new species is most similar to P. membranifolia, P. pengzhouensis, and P. mianyangensis within the same section, all of which share the following characteristics: aboveground parts farinose, calyx campanulate or narrowly campanulate, and leaves obovate or sub-spatulate. However, it is distinguished from the three species mentioned above by the following morphological features: petiole with broad wings, 7–8-lobed corolla and calyx, corresponding 7–8 stamens, floral type uniform: stamens of all flowers inserted at the middle of the corolla tube, free from the tube at the mouth, extending ca. 5 mm beyond the tube, style 2.5–3 cm long, longer than the stamens (Figs 1, 2). A comparison of plant photographs of P. exserta with P. membranifolia, P. pengzhouensis, and P. mianyangensis is provided in Fig. 3, and the main morphological differences are summarized in Table 1.

Etymology. The specific epithet exserta is derived from the Latin exsertus, meaning “protruding” or “extended outward,” alluding to the style and stamens that are distinctly exserted beyond the mouth of the corolla tube, a key diagnostic character distinguishing this species from its congeners in P. sect. Aleuritia.

Vernacular name. Simplified Chinese: 大围山报春; 

Chinese Mandarin: “dà wéi shān bào chūn.”

 Li Yang, Gui-Liang Zhang, Yang-Yang Zheng, Qing-Qing Ye, Xin Tan, Lei Cai and Zhi-Kun Wu. 2026. Primula exserta (Primulaceae), A New Species in Primula sect. Aleuritia from Yunnan, China. PhytoKeys. 278: 117-125. DOI: doi.org/10.3897/phytokeys.278.202553 [14 Aug 2026] 

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

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

in Wei, J.-Y. Li, Chen, Y. Nong, Hu, Y.-J. Li, Ji, Xu et Y.-K. Nong. 2026. 

忻城螺序草  |  DOI: doi.org/10.3897/phytokeys.278.194094

Abstract

Ophiorrhiza xinchengensis (Rubiaceae), a new species from the middle part of Guangxi, China, is described and illustrated on the basis of morphological evidence. This new species resembles Ophiorrhiza longanensis in its densely pubescent stems, linear stipules, terminal or upper axillary inflorescences, but it can be distinguished by its elliptic or oblanceolate leaf blade, base attenuate (vs. oval, ovate to broadly ovate, base cuneate), its 2–3 mm long stipules (vs. 3.8–6.5 mm long), its 3–5 mm long bracteoles (vs. 6–10 mm long) its 10–12 mm long corolla tubes (vs. 2–3 mm long) and its filaments adnate at the middle of corolla tube, styles 12–15 mm long (vs. adnate to the base of corolla tube and styles ca. 3 mm long). The new species is currently known from a single population with approximately 60–100 mature individuals. Following IUCN Criteria, it is provisionally assessed as Critically Endangered. Photographs, an illustration and a distribution map are also provided.

Key words: Karst, new species, Ophiorrhiza, Spiradiclis, taxonomy

Ophiorrhiza xinchengensis Y.Nong & G.Y.Wei.
A. Habitat; B, C. Flowering plant; D. Stem, showing the linear stipules; E. Inflorescences; F. Fruiting plant; G. Dissected brevistylous flower; H. Dissected longistylous flower; I. Hypanthium, calyx, style and stigma; J. Ovary and calyx; K. Stigma; L. Bracts; M, N. Leaf (abaxially and adaxially); O. Capsule; P. Seeds.

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

 

Chinese name. “xīn chéng luó xù cǎo” (忻城螺序草).

Diagnosis. Ophiorrhiza xinchengensis is resembles Ophiorrhiza longanensis (R.J.Wang) Razafim. & Rydin in its densely pubescent stems, linear stipules, terminal or upper axillary inflorescences, but it can be distinguished by its elliptic or oblanceolate leaf blade, base attenuate (vs. oval, ovate to broadly ovate, base cuneate), its 2–3 mm long stipules (vs. 3.8–6.5 mm long), its 3–5 mm long bracteoles (vs. 6–10 mm long), its 10–12 mm long corolla tubes (vs. 2–3 mm long) and its filaments adnate at the middle of corolla tube, styles 12–15 mm long (vs. adnate to the base of corolla tube, styles ca. 3 mm long).

Etymology. The specific epithet “xinchengensis” refers to the type location of the new species.

 Gui-Yuan Wei, Jin-Yue Li, Rong Chen, You Nong, Qi-Min Hu, Ying-Jing Li, Xing-Yun Ji, Chuan-Gui Xu, Yun-Kai Nong. 2026. Ophiorrhiza xinchengensis (Rubiaceae), A New Species from Guangxi, China. PhytoKeys. 278: 1-14.  DOI: doi.org/10.3897/phytokeys.278.194094 [24-07-2026]

[Botany • 2026] Ophiorrhiza saxatilis (Rubiaceae) • A New Species from Guizhou, China

Ophiorrhiza saxatilis M.T.An & G.L.Li,

in Li, An, Wu, Yu, Qiu, Liu et Tan, 2026. 

 岩生蛇根草  ||  DOI: doi.org/10.3897/phytokeys.278.197480

Abstract

Ophiorrhiza saxatilis M.T.An & G.L.Li, sp. nov., a new species of the genus Ophiorrhiza (Rubiaceae) discovered in the karst regions of Guizhou, China, and provides its taxonomic basis from a morphological perspective. The new species is morphologically similar to Ophiorrhiza lignosa, but differs from the latter by having an inflorescence in that its young branches are uniformly pubescent (vs. bifariously pubescent in O. lignosa); the abaxial leaf surface is pubescent (vs. puberulent only along the midrib and secondary veins in O. lignosa); the bracteoles are 5–6 mm long (vs. 1.5–3 mm long in O. lignosa); the petioles are 2–5.8 mm long (vs. 6–20 mm long in O. lignosa); the stamens are inserted at the base of the corolla tube (vs. inserted near the middle of the corolla tube in O. lignosa); the flowers are distylous (vs. monomorphic with pin flowers in O. lignosa), and the styles of long-styled flowers are 6–8 mm long (vs. 10–11 mm long in O. lignosa). These stable and significant morphological differences, combined with a comprehensive and detailed morphological description of the new species and a comparison of diagnostic characters with similar species, firmly support the recognition of Ophiorrhiza saxatilis as a distinct new species.

Key words: Karst, Morphology, New Taxon, Ophiorrhiza, Rubiaceae

Ophiorrhiza saxatilis.
A, B. Habitat; C. Plant; D. Flowering branch; E. Dissected flowers: long-styled flower (above) and short-styled flower (below); F. Style of long-styled flower; G. Style of short-styled flower; H. Longitudinally dissected short-styled flower; I. Longitudinally dissected long-styled flower; J. Fruit; K. Infructescence; L. Adaxial leaf surface; M. Abaxial leaf surface; N. Branchlets.

Ophiorrhiza saxatilis M.T.An & G.L.Li, sp. nov.

Diagnosis. Ophiorrhiza saxatilis is morphologically similar to O. lignosa Merr., but can be distinguished by several key characteristics (Table 2): uniformly pubescent young branches (vs. bifariously pubescent); white corolla lobes with ridges (vs. purple, without ridges); stamens inserted at the base of the corolla tube (vs. inserted near the middle of the corolla tube); flowers distylous (vs. monomorphic, with pin flowers); long-styled flowers 6–8 mm long (vs. 10–11 mm long); purple midrib on the abaxial leaf surface (vs. green); abaxial leaf surface pubescent (vs. puberulent only on the midrib and secondary veins); bracteoles 5–6 mm long (vs. 1.5–3 mm long); and petioles 2–5.8 mm long (vs. 6–20 mm long).

Etymology. The specific epithet is derived from the habitat of the new species, which occurs in a typical karst limestone environment. It mainly grows in harsh habitats such as rock crevices and stony slopes.

Local name. Simplified Chinese: 岩生蛇根草;
Chinese Pinyin: yán shēng shé gēn cǎo.

 Guang-Lin Li, Ming-Tai An, Xu Wu, Jiang-Hong Yu, Jian Qiu, Shao-Fei Liu and Cheng-jiang Tan. 2026. Ophiorrhiza saxatilis (Rubiaceae), A New Species from Guizhou, China. PhytoKeys. 278: 27-37.  DOI: doi.org/10.3897/phytokeys.278.197480 [24-07-2026]

[Botany • 2026] Microlicia almedae (Melastomataceae) • A New Species from the Chapada Diamantina, Bahia, Brazil

Microlicia almedae  R.B.Pacifico & Kriebel,

in Pacifico et Kriebel, 2026. 

DOI: doi.org/10.3897/phytokeys.276.193021

Abstract

A new species, Microlicia almedae, is described and illustrated from the species-rich campo rupestre vegetation of Chapada Diamantina, Bahia, Brazil. The taxonomic novelty is morphologically related to M. giuliettiana and M. pulchra, which are also restricted to Chapada Diamantina. Microlicia almedae differs from the latter two species in leaf shape and size, hypanthium indumentum, calyx lobe shape and size, and petal size. In addition, M. almedae differs from M. giuliettiana by its uniformly magenta petals and from M. pulchra by its capsules with deciduous columellae. Variation in leaf shape among M. almedae, M. pulchra, and M. giuliettiana was quantified using elliptic Fourier analysis, which revealed near-complete separation among the three species.

Key words: Campo rupestre, Lavoisiereae, Pico da Lapa Grande, Serra do Barbado, taxonomy

Microlicia almedae.
 A. Habit; B. Flower; C. Landscape with campo rupestre vegetation at Serra do Barbado, the type locality of M. almedae.

Voucher: L. Daneu et al. 796 (JABU). 

Photos: by L. Daneu (A, B); by E.A. Ramos (C).

Microlicia almedae.
A. Habit; B. Close-up of a branch; C. Leaf adaxial surface; D. Leaf abaxial surface; E. Detail of glandular-punctate adaxial surface; F. Detail of glandular-punctate indumentum on abaxial surface; G. Flower in lateral view; H. Flowering hypanthium and calyx lobes; I. Detail of the indumentum on the hypanthium; J. Petal in adaxial view; K. Antepetalous (left) and antesepalous (right) stamens; L. Gynoecium; M. Apex of style and stigma; N. Ovary in cross-section; O. Capsule enveloped by the hypanthium and calyx lobes; P. Seed in lateral view.

Illustration by Klei Sousa based on L. Daneu et al. 796 (JABU).

  

Microlicia almedae R.B.Pacifico & Kriebel, sp. nov.

Ricardo Pacifico and Ricardo Kriebel. 2026. Microlicia almedae (Melastomataceae), A New Species from the Chapada Diamantina, Bahia, Brazil. PhytoKeys. 276: 183-195. DOI: doi.org/10.3897/phytokeys.276.193021 [12 Jun 2026]

 

[Botany • 2026] Ceropegia gengmaensis (Apocynaceae: Ceropegieae) • A New Species from Yunnan, China

 

Ceropegia gengmaensis  P.R.Luo, A.Liu & H.Sun,

in Luo, Liu, Tong, Zhang, Wang, Deng, Goyder et Sun, 2026. 

耿马吊灯花  ||  DOI: doi.org/10.3897/phytokeys.276.197333

Abstract

Ceropegia gengmaensis P.R.Luo, A.Liu & H.Sun, a new species from Gengma County, Yunnan, Southwest China, is described. Both morphological characteristics and chloroplast phylogenetic analysis strongly support its placement within C. sect. Chionopegia H.Huber. Molecular data further reveal that C. gengmaensis is closely related to C. salicifolia, C. mairei, and C. dolichophylla, yet it can be distinguished from them readily by its stem indumentum, leaf shape, and floral morphology, particularly the shape of the corolla tube, and features of the lobes. A detailed line drawing of this new species is also provided.

Key words: Ceropegieae, Chloroplast, Karst Landform, Morphology, Southwest China

Ceropegia gengmaensis. 
 A, B. Plant showing the rootstock; C, D. Upper and lower sides of leaf; E. Inflorescence with bases of adjoining leaves; F. Corolla tube dissected longitudinally; G. Side view of gynostegium (with sepals and pedicel shown); H. Top view of gynostegium with sepals shown; I. Ovary; J Pollinarium.

 Scale bars: 15 cm (A, B); 5 cm (C, D); 4 cm (E, F); 1 cm (G); 0.8 cm (H); 0.3 cm (I); 0.5 mm (J).

Morphological features of Ceropegia gengmaensis based on living plants collected from the type locality.
 A. Plant showing the rootstock; B, C. Leaf: B, abaxial surface and C, adaxial surface; D. Stem; E, F. Corolla: E, corolla from the outside with its base cut off and F, corolla with the tube dissected longitudinally; G. Small peduncle, part of the pedicel and petiole; H. White hairs on the inside of the base of the tube; I. Side view of gynostegium; J. Gynostegium from above; K. Pollinarium.

Scale bars: 15 cm (A); 5 cm (B, C); 4 cm (D, E, F); 1 cm (G, H, I); 0.8 cm (J); 0.5 mm (K).

Ceropegia gengmaensis P.R.Luo, A.Liu & H.Sun, sp. nov.

 

Diagnosis. Ceropegia gengmaensis shows affinities with C. salicifolia and C. dolichophylla, both of C. sect. Chionopegia . It differs from C. salicifolia by its erect to sprawling habit (vs. twining), elliptic leaves 2.0–5.5 cm (vs. lanceolate, 6–15 cm), densely pubescent stems bearing usually solitary flowers (vs. glabrous stems with sessile cymose many-flowered inflorescences), and narrower corolla lobes with only slight expansion above the throat (vs. lobes longer and wider, upper portion markedly expanded). From C. mairei it differs by the much less pronounced basal inflation of the tube (vs. a strongly inflated tube) and ... 

Etymology. Ceropegia gengmaensis is named after its type locality, Gengma County, Southwest Yunnan.

Vernacular name. the Chinese name is given as “耿马吊灯花” (gěng mă diào dēng huā) named after the type locality, Gengma County, Southwest Yunnan.

Peng-Rui Luo, Ang Liu, Rui Tong, Xin-Jian Zhang, Zi-Yi Wang, Tao Deng, David J. Goyder and Hang Sun. 2026. Ceropegia gengmaensis (Apocynaceae), A New Species from Yunnan, China. PhytoKeys. 276: 217-228. DOI: doi.org/10.3897/phytokeys.276.197333 [15 Jun 2026]

[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] Polystemma cualense (Apocynaceae: Asclepiadoideae) • A New Species from western Mexico

Polystemma cualense  C.D.Sánchez, S.Islas & A.Black, 

in Sánchez-Sánchez, Islas-Hernández et Black, 2026. 

DOI: doi.org/10.3897/phytokeys.276.176723 

Abstract

A new species of Polystemma is described from the Sierra El Cuale, Jalisco, Mexico. Polystemma cualense is distinguished from its congeners, particularly P. horconesense, by a gynostegial corona higher than the gynostegium, longer external corona lobes, and a black gynostegium. Morphological data were obtained by examining herbarium specimens, consulting digital images from iNaturalist, and reviewing specialized literature. A preliminary conservation assessment based on IUCN criteria indicates that it is a Critically Endangered (CR) species due to its restricted area of occupancy and threats from deforestation, agriculture, and livestock grazing. The discovery of P. cualense increases the known diversity of Polystemma in Jalisco and highlights the floristic importance of the Sierra El Cuale.

Key words: Asclepiadoideae, high diversity, Jalisco, Sierra El Cuale

Polystemma cualense.
A. Complete plant; B. Inflorescence; C. Detail of gynostegium; D. Pollinarium. E. Immature follicle with sepal remnants.

Polystemma cualense C.D.Sánchez, S.Islas & A.Black, sp. nov.

  

Diagnosis. Polystemma cualense resembles P. horconesense in having flowers similar in size and shape. Polystemma cualense differs in having a gynostegial corona higher than the gynostegium (vs. gynostegial corona the same height as the gynostegium), external gynostegial corona lobes 3–4 mm length (vs. 0.5–0.6 mm length) and gynostegium black (vs. gynostegium green-yellowish).

 Cristóbal Daniel Sánchez-Sánchez, Carla Sofía Islas-Hernández and Adam W. Black. 2026. Polystemma cualense (Apocynaceae), A New Species from western Mexico. PhytoKeys. 276: 245-251. DOI: doi.org/10.3897/phytokeys.276.176723   [18 Jun 2026]

 

[Botany • 2018] Lobelia hongiana (Campanulaceae) • A New Species from Guangxi, China

Lobelia hongiana Q.F.Wang & G.W.Hu, 

in Li, Wei, Liu, Chen, Hu et Wang, 2018.

 DOI: doi.org/10.3897/phytokeys.95.20245

Abstract

Lobelia hongiana, a new species of Campanulaceae from Guangxi, South China, is described and illustrated here. This new species is most similar to L. chinensis and L. loochooensis, but differs by its elliptic-obovate or oblanceolate leaf, 2.5–3 mm long greenish-carmine hypanthium, 5 or 6 calyx lobes, purplish-white corolla, with yellowish-green blotches at the base of lower lobes, glabrous filaments, 7–8 mm long broadly obconic capsule. Molecular phylogenetic analysis has been conducted based on ITS and two chloroplast sequences (atpB and rbcL) and 14 taxa in Lobelia are included. L. hongiana is well supported as a new species by the evidence from both morphology and molecular phylogeny.

Keywords: Hypsela, Lobelia chinensis, Lobelia loochooensis, Southern China

 

Photos of Lobelia hongiana Q.F.Wang & G.W.Hu: morphology.
A Habitat B Part of one individual C A stem bearing leaves and a flower D–G Flower viewed from different orientations H–I Fruit viewed from different orientations.

Lobelia hongiana Q.F.Wang & G.W.Hu, sp. nov.

Diagnosis: The new species is distinguished from L. chinensis and L. loochooensis by its elliptic-obovate or oblanceolate leaves, usually sinuate-dentate margin; hypanthium 2.5–3 mm long, greenish-carmine; calyx lobes 5 or 6, shorter than hypanthium; corolla purplish-white, yellowish- green blotches at the base of lower lobes; glabrous filaments; broadly obconic capsule, 7–8 mm long; flowering time from May to July.

 

Distribution and ecology: The new species has been found in Huixian Wetland, Guangxi Zhuang Autonomous Region in China, with only two populations. There is a high probability that L. hongiana is also distributed at adjacent areas, given its vegetative propagation traits. Its living environment is wetland and farmland.

Phenology: The new species was found in flower from May to July.

Etymology: Species epithet, “hongiana”, is in honour of Prof. De-Yuan Hong who made a significant contribution to the authors’ knowledge of Campanulaceae.

 Zhi-Zhong Li, Neng Wei, Yan Liu, Jin-Ming Chen, Guangwan Hu and Qing-Feng Wang. 2018. Lobelia hongiana (Campanulaceae), A New Species from Guangxi, China. PhytoKeys. 95: 27-36.  DOI: doi.org/10.3897/phytokeys.95.20245

[Botany • 2026] Oreocharis sihuiensis (Gesneriaceae) • A critically endangered New Species from Guangdong Province, China

 

Oreocharis sihuiensis  L.B.Ji & F.Wen, 

in  Ji, Wen, Jin, Xu, Li et Tang. 2026. 

四会瑶山苣苔  ||  DOI: doi.org/10.3897/phytokeys.276.190710 

Abstract

Oreocharis sihuiensis sp. nov. (Gesneriaceae) is described from Guangdong Province, China. Morphologically, the flower shape of this new species is similar to that of O. dayaoshanioides, but it can be distinguished by its leaf blade being adaxially densely pubescent, with hairs 0.2–0.5 mm long (vs. adaxially sparsely villous to villous, with hairs longer than 1 mm), lobes of the corolla upper lip subrounded and apex rounded (vs. broadly ovate to orbicular-ovate and apex acute), 3 staminodes (vs. absent or 2), disc margin cleft (vs. subentire), shorter filaments (ca. 6.0 mm long vs. 8.0–12.0 mm long), and shorter capsules (ca. 1.0 cm long vs. ca. 2.0 cm long). Considering its scarce number of individuals, and the presence of severe human disturbance, we preliminarily assess the new species as ‘Critically Endangered’ (CR) according to IUCN Red List Categories and Criteria.

Key words: Medicinal plant, morphology, new taxon, Oreocharis cotinifolia, Oreocharis dayaoshanioides, taxonomy

Oreocharis sihuiensis sp. nov.
A. Habit; B, C. Flowering individuals; D. Leaves, adaxial (left), abaxial (right), and their partially magnified views (a, b. Respectively, showing indumentum); E. Inflorescence; F, G. Flowers, front and lateral view, respectively; H. Longitudinal section of corolla, lower lip (left), upper lip (right) and its partially magnified view (a. Showing indumentum and staminodes); I. Calyx lobes; J. Disc and Pistil; K. Capsules.

Oreocharis sihuiensis sp. nov.
A. Habit; B. Front view of a flower; C. Lateral view of a flower; D. Longitudinal section of corolla; E. Disc and Pistil; F. Capsules; G. Leaf, abaxial surface.

Oreocharis sihuiensis L.B.Ji & F.Wen, sp. nov.

Diagnosis. A species similar to Oreocharis dayaoshanioides Yan Liu & W.B.Xu (in Liu et al. 2012), but can be distinguished from the latter by the adaxial leaf blade being densely pubescent with hairs 0.2–0.5 mm long (vs. sparsely to densely villous, hairs longer than 1 mm), lobes of the corolla upper lip subrounded with a rounded apex (vs. broadly ovate to orbicular-ovate with an acute apex), presence of 3 staminodes (vs. absent or 2), disc margin cleft (vs. subentire), filaments shorter, less than ca. 6.0 mm long (vs. 8.0–12.0 mm), and capsules ca. 1.0 cm long (vs. ca. 2.0 cm). (Table 1, together with the type species of Dayaoshania, now namely Oreocharis cotinifolia).

Etymology. Specific epithet is derived from the type locality, Sihui City.

Vernacular name. Sì Huì Yáo Shān Jù Tái (Chinese pronunciation); 

四会瑶山苣苔 (Chinese name).

Ling-Bo Ji, Fang Wen, Xiu-Hui Jin, Yi-Da Xu, Bo-Heng Li and Bo Tang. 2026. Oreocharis sihuiensis (Gesneriaceae), A critically endangered New Species from Guangdong Province, China. PhytoKeys. 276: 175-182. DOI: doi.org/10.3897/phytokeys.276.190710 [12 Jun 2026]

[Botany • 2026] Oreocharis fulvovillosa (Gesneriaceae) • A New Species from western Yunnan, China

Oreocharis fulvovillosa  M.Q.Han, H.Jiang & Y.Wang,

in Wang, Jiang, Xu et Han, 2026. 

德宏直瓣苣苔  ||  DOI: doi.org/10.3897/phytokeys.276.182136

Abstract

Oreocharis fulvovillosa, a new species of Gesneriaceae, is described and illustrated. This new species has only been discovered on the rock walls of an isolated karst hill at its type locality in Mang City, western Yunnan, China.

Key words: Flora of Yunnan, karst, yellow flowers

 

Oreocharis fulvovillosa sp. nov.
A. Habitat; B. Plant habit in natural habitat; C. Adaxial (left) and abaxial (right) leaf surfaces; D. Petiole with long fulvous indumentum; E. Rhizomatous stem; F. Flower in adaxial view; G. Flower in abaxial view; H. Flower in side view; I. Flower longitudinally cut, male stage with immature pistil; J. Flower transversely cut, male stage with immature pistil; K. Immature pistil and stamens with dehisced anthers cohering in pairs; L. Flower in front view; M. Capsules at different developmental stages: two immature capsules (left) and two dehisced capsules from the previous year (right); N. Pistils at different developmental stages: left, at flower opening with immature stigma; middle and right, at stigma maturity; O. Transverse sections of ovaries, all arranged with the dorsal calyx lobe positioned upwards: upper image, ovary at stigma maturity; lower images, ovary with immature stigma, showing transverse sections of the upper part of the ovary (left) and the lower part of the ovary (right).

Oreocharis fulvovillosa M.Q.Han, H.Jiang & Y.Wang, sp. nov.

 

Diagnosis. The new species is most similar to Oreocharis bullata, sharing yellow corollas and bullate leaf blades, but differs in having crenulate leaf margins (vs. double dentate), a slender corolla tube ca. 1 cm long (vs. tubular, ca. 2.7 cm long), and shorter capsules 1–1.9 cm long (vs. 3.0–4.2 cm long). It is also similar to Oreocharis fulva in corolla shape and colour but differs in having bullate leaf blades (vs. not bullate) and crenulate margins (vs. serrate to crenate).

Etymology. The epithet refers to the fulvous (yellowish) colour of the long, soft hairs on the petioles.

Vernacular name. Chinese Mandarin: dé hóng zhí bàn jù tái, (德宏直瓣苣苔).

Yang Wang, Hong Jiang, Bo Xu and Meng-Qi Han. 2026. Oreocharis fulvovillosa (Gesneriaceae), A New Species from western Yunnan, China. PhytoKeys. 276: 17-23.  DOI: doi.org/10.3897/phytokeys.276.182136 [08-06-2026]