Phytotaxa

**A revision of the Neotropical species of Adenostemma (Asteraceae, Eupatorieae)**

FLORENCIA D. DOSIL HIRIART, LILIANA KATINAS — Thu, 15 Oct 2026 00:00:00 +1300

Adenostemma (Asteraceae, Eupatorieae) consists of ca. 26 species, inhabiting the continental Neotropics and Paleotropics, with populations also occurring in islands, many of them remote. The 10 Neotropical species are revised. They comprise herbs and subshrubs whose capitula have a soft receptacle, a distinctive glandular pappus, and cypselae covered by glandular trichomes; these capitulum features facilitate epizoochory. As a result of this revision: A. involucratum, A. cuatrecasasii and A. platyphyllum are considered synonyms of A. brasilianum; a lectotype is designated for A. suffruticosum and A. hirtiflorum; the geographic distribution was extended for A. harlingii, A. vargasii, and A. zakii. The morphology of vegetative and reproductive organs is investigated. A comprehensive key to the species and descriptions, geographical distribution, phenology, illustrations and distribution maps are provided for all taxa.

Sedum pingyuanense (Crassulaceae), a new species endemic to danxia landscape from Guangdong Province, China

Thu, 15 Oct 2026 00:00:00 +1300

Sedum pingyuanense J.M. Dai, W.B. Liao & Q. Fan, a new species from the danxia landscape in Pingyuan County, Guangdong Province, is illustrated and described here. Phylogenetic analysis based on the internal transcribed spacer (ITS) region of nrDNA indicates that this new species belongs to S. sect. Sedum sensu Fu and Ohba (2001) in Flora of China, and is sister to S. polytrichoides var. setouchiense, with high support values (BS = 96, PP =0.98). Despite this close relationship, the two species are clearly distinct. S. pingyuanense has opposite phyllotaxy, unlike the alternate arrangement in S. polytrichoides complex. Morphologically, S. pingyuanense resembles S. jinglanii in having opposite leaves but differs in leaf shape (narrow-lanceolate to oblong vs. spatulate or obovate), inflorescence (few-flowered vs. dense terminal cymes), and anther color (yellow vs. brownish red).

**A new species of Cortinarius (Agaricales, Basidiomycota) from Guangxi Autonomous Region, South China**

SEN LIU, GUANG-YU ZENG, YA-LIN ZHAO, TIE-ZHENG WEI, YU-CHENG DAI — Thu, 15 Oct 2026 00:00:00 +1300

A new species of Cortinarius subgenus Telamonia section Laeti is described from the mountainous region of Guangxi, South China, based on morphological characteristics and internal transcribed spacer (ITS) phylogeny. This species is distinguished by its small basidiomata (pilei 10–30 mm), hygrophanous brown pileus, moderately to distantly spaced lamellae, and a slender, fibrillose-striate stipe (30–50 × 2.1–2.8 mm) without conspicuous veil remnants. Microscopically, the species possesses ellipsoid to oblong-ellipsoid basidiospores (7.6–11.7 × 4.3–6.6 µm) with irregular verrucae. Specimens were collected from the forest floor in a Tsuga tchekiangensis stand and form a strongly supported lineage, sister to C. paradetonsus (BS = 98%, BPP = 0.98). An illustrated description and a comparison with related species are presented.

**A new species from Guyana related to Navia splendens L.B. Sm. and an identification key to the species of the genus Navia (Bromeliaceae)**

ERIC J. GOUDA — Thu, 15 Oct 2026 00:00:00 +1300

A new species Navia reddenii from Guyana that keys out to Navia splendens L.B. Sm. because of its superior ovary and free sepals, but in coloration it more resembles N. igneosicola L.B.Sm., Steyerm. & H.Rob. because of the bright leaf coloration and indument type. This new species grows as an epiphyte (vs. litophyte in N. splendens and N. igneosicola), with very colorful inner leaves at anthesis like in N. igneosicola, that are green apically then yellow then red then yellow again (vs. the inner leaves turning to yellow or orange at the base often with red margins in N. splendens), and white petals (vs. yellow in N. splendens and yellow-orange with pinkish apex in N. igneosicola). There are several differences in the flower characteristics, like a superior ovary (vs. inferior in N. igneosicola), it has white petals (vs. orange to red in both other species). The new species is described illustrated here and compared with the morphologically most closely related and alike species. Additionally, an updated identification key to the species of the genus Navia is presented here.

Placoneis montana sp. nov. (Bacillariophyta), a new diatom species from a small mountain stream

Thu, 15 Oct 2026 00:00:00 +1300

During the survey on the diatom diversity in mountain streams of the Gorce Mountains National Park (southern Poland), several unidentified taxa were observed. Comparison with available literature and detailed morphological analyses using light microscopy (LM) and scanning electron microscopy (SEM) confirmed a set of distinct valve features in one of the taxa that could not be assigned to any known taxa. As a result, Placoneis montana sp. nov. is described as a new species. A detailed morphological comparison with similar taxa is provided, along with information on the associated diatom assemblage. This new Placoneis species expands knowledge of morphological and ecological variation in the genus, and its lack of visible areola occlusions raises questions about the reliability of that character for separating Placoneis from Witkowskia, pointing to the need for further SEM-based comparison across related taxa. Additionally, observations based on the type locality suggest that the new species is associated with high-altitude, well-oxygenated, low-nutrient environments, emphasising their potential value as indicators of mountain stream conditions.

Ophiopogon spathulifolius (Asparagaceae), a new species from northern Vietnam, and O. robustus new to the country

Thu, 15 Oct 2026 00:00:00 +1300

Ophiopogon spathulifolius, a new species from Tuyen Quang Province (including former Ha Giang Province), northern Vietnam, is described and illustrated. It is distinguished from all other species of the genus by a combination of character states: estoloniferous habit with a short rhizome, petioles with scarious whitish wings dilated toward the base, spathulate and abaxially whitish leaf blades (up to 24 cm long, up to 2.4 cm wide), and subsessile narrowly deltoid anthers (2.6–2.9 mm long). Data on its ecology and distribution are also provided. Furthermore, the occurrence of O. robustus is reported from Son La Province, northwestern Vietnam. As this species was previously known only from Laos, this finding represents a new record for the flora of the country.

**Nomenclatural notes on Paepalanthus ser. Rosulati (Ruhland) Giulietti (Eriocaulaceae)**

MYLENA CABRINI, CLAUDIO NICOLETTI DE FRAGA, CATARINA F LIRA, MARCELO TROVÓ — Thu, 15 Oct 2026 00:00:00 +1300

Eight names historically included in Paepalanthus ser. Rosulati (Ruhland) Giulietti are revised through the examination of the protologues and type specimens. Notes are provided for all names, clarifying formal and historical aspects of their application, including the designation of four lectotypes (P. ser. Rosulati, P. aretioides, P. hispidissimus, and P. sedoides). In this sense, our study contributes to the nomenclatural stability of the group and supports future taxonomic and evolutionary studies.

**Two new combinations in the genus Leptochilus (Polypodiaceae)**

ANDRIY KOVALCHUK, CHRISTOPHER ROY FRASER-JENKINS — Thu, 15 Oct 2026 00:00:00 +1300

In our recent survey (Kovalchuk & Fraser-Jenkins, 2024), we identified a neglected fern name Gymnogramma (‘Gymnogramme’) plantaginea Sprengel (1827: 39) that was largely overlooked by subsequent authors. This name provides a legitimate replacement name for Hemionitis plantaginea Don (1825: 13), nom. illeg. (non H. plantaginea Smith (1793: 421) nec H. plantaginea Cavanilles (1802: 260)). We also identified a specimen deposited at BM (BM001038409) as original material for this name and designated it as the lectotype for G. plantaginea. The specimen can be identified with the taxon currently recognized by various authors either as Leptochilus hemionitideus (Presl 1836: 216) Nooteboom (1997: 285) or L. decurrens Blume (1828: 206) subsp. hemionitideus (C.Presl) Fraser-Jenkins (2008: 63) (Polypodiaceae), a fern widely distributed in South, East and South-East Asia (Nooteboom, 1997; Fraser-Jenkins et al., 2021).