Phytotaxa

Osbeckia zubeengargiana (Melastomataceae), a new species from Assam, Northeast India

BARNALI DAS — 2026-03-13

A new species of Osbeckia, O. zubeengargiana, from the family Melastomatacaeae, is described based on collections made from Assam, India. The new species is related to O. rostrata because of its tetramerous flowers, but can be distinguished by its habit, foliar morphology, bract shape and size, morphology of the intersepalar emergences, ciliated style base, and seed size. Detailed taxonomic descriptions, photographs showing diagnostic features, and comparison with the related species are provided here.

Talaromyces doitungensis sp. nov. and new records from Doi Tung National Forest in Thailand

SUBASINGHA A.D. THAKSHILA — 2026-03-13

Talaromyces (Eurotiales, Trichocomaceae) is a monophyletic genus with species that impact the environment, human health, and various industries. Talaromyces consists of eight sections, and their ecology, diversity, and number of recognised species are rapidly expanding due to advances in morpho-molecular studies. In this study, we analyse the fungal diversity of soil samples collected from the Doi Tung Forest areas, which are dominated by Pinus kesiya in Chiang Rai, Thailand. Morphological and multi-gene phylogenetic analyses of internal transcribed spacer (ITS1-5.8S-ITS2), ß-tubulin (BenA), calmodulin (CaM), and the second largest subunit of the DNA-directed RNA polymerase II (rpb2) sequences were used to confirm the taxonomic placements of the new isolates. Herein, we describe Talaromyces doitungensis as a new species, report T. rubidus for the first time in Thailand (marking its second global record). Further, multi-gene phylogenetic analyses confirmed the distinct placement of these species and determined their relationships, supporting their recognition based on the phylogenetic species concept. In addition, preliminary antibacterial screening revealed that Talaromyces rubidus exhibited activity against Bacillus subtilis. Our findings contribute to the understanding of Talaromyces diversity and ecology by documenting a new species and new geographic records from pine-dominated forest soils in northern Thailand, and further studies are necessary to explore the bioactive compounds produced by Talaromyces species.

**Seed morphological and morphometric traits as diagnostic tools for species-level classification in Indian Eulophia Lindl. (Eulophiinae; Orchidaceae)**

MAYUR JADHAV — 2026-03-13

The present study evaluates whether seed morphometric and morphological traits can serve as reliable diagnostic tools for species-level classification within the genus Eulophia. Earlier phylogenetic studies have revealed paraphyly within the genus, indicating unresolved generic boundaries and uncertain relationships within the subtribe Eulophiinae. These contradictions in phylogenetic placement highlight persistent taxonomic challenges, necessitating supplementary morphological approaches to clarify species delimitation and evolutionary relationships. In this context, seed morphology and morphometry offer valuable insights. Using light microscopy and scanning electron microscopy, ten species of Eulophia were analyzed for testa and embryo dimensions, testa-to-embryo volume ratios, air space, and surface ornamentation. Testa length ranged from 0.493–1.619 mm and testa width from 1.586–2.734 mm, with testa-to-embryo volume ratios varying from 3–21, reflecting species-specific patterns. Cluster analysis grouped the species into three major clusters, with E. graminea occupying an intermediate position that linked two groups. In the current study, almost all species having air space exceeded 80%, indicating adaptations for wind-mediated seed dispersal. Importantly, all the species used in this study reflect diverse habitats across India, thereby representing the full range of Eulophia taxa available in the country. Seed morphology supports the taxonomic value of seed traits. The morphometric variation is discussed in the context of dispersal related attributes and their significance as baseline data for the conservation of the genus Eulophia.

**Morphological variability of Carex ×vratislaviensis (Cyperaceae) and its parent species—case from Central Europe**

RADOMÍR ŘEPKA — 2026-03-13

The article analyzes morphological variability and the possibility of distinguishing the hybrid sedge Carex ×vratislaviensis and its wetland parent species C. acuta and C. buekii in Central Europe. A large amount of data was obtained from herbarium material by measuring or evaluating 14 quantitative traits, 2 ratios and 8 qualitative features in 32 populations of the three taxa collected in Central Europe. The data were analysed by Dunn’s test and discriminant function analysis (DFA). Specimens of C. acuta, C. buekii and C. ×vratislaviensis form three clearly separate groups distinguishable by combination of 8 features: utricle length, presence of veins on the utricle surface, length of lowest inflorescence bract, width of female spikes, leaf width, stem length, spikes fertility and presence of the interrupted base of lowest female spike. The analysis also confirms the assumption of extensive variability of hybrid populations observed in the field. Intermediate morphotypes as well as variable plants closer to one or the other parent species are common. The length of the lower inflorescence bract, the length of the peduncle of the lower female spike, the length of the inflorescence and the length of the utricle are the traits that best characterize the studied hybrid.

**Taxonomic notes on Dendrobium sect. Pedilonum (Orchidaceae): a new species, D. nakhonsiense, from Thailand and the D. cumulatum s.l. complex revisited**

WIRATA RUJICHAIPIMON — 2026-03-13

This study presents a classical taxonomic approach to parts of Dendrobium sect. Pedilonum, focusing on a newly discovered species from Thailand and the D. cumulatum s.l. species complex. The new species, D. nakhonsiense seems endemic to Nakhon Si Thammarat Province in Peninsular Thailand where it is only known from one location. It is morphologically close to D. cowenii but is distinguished by its slightly larger flowers with a relatively longer, obtuse to rounded mentum and by its differently shaped dorsal sepal and labellum lamina. The D. cumulatum s.l. complex includes four taxa, viz. D. cumulatum, D. rhodocentrum, D. eoum, and D. calicopis. Based on extensive herbarium studies and morphological comparisons, we propose the recognition of two distinct species: D. cumulatum (syn.: D. rhodocentrum, D. calicopis) and D. eoum. Our findings contribute to the understanding of species diversity and distribution within Dendrobium sect. Pedilonum.

**A new species and taxonomic notes on Gouania (Rhamnaceae, Gouanieae) from South America**

MAURÍCIO FIGUEIRA — 2026-03-13

Gouania, with ca. 70 species, is one of the largest genera within Rhamnaceae and forms a well-supported clade along with six other genera in the tribe Gouanieae. Despite recent progress in the delimitation of the genus, numerous taxonomic issues remain unresolved among the South American species, particularly regarding species circumscriptions, as well as the validation and typification of several taxa, especially those published in the 19th century. This study represents part of a taxonomic revision of the South American taxa of Gouania that is currently underway, including the description of a new species, Gouania neglecta, as well as the typification of five South American species: Gouania alnifolia, G. discolor, G. podocephala, G. rumicina, and G. ulei.

**A new peat-associated omphalinoid species from Europe: Arrhenia turficola sp. nov. (Agaricomycetes, Agaricales, Hygrophoraceae)**

PIERRE-ARTHUR MOREAU — 2026-03-13

A new peat-associated species of Arrhenia, A. turficola sp. nov., is described. Hitherto known from continental Europe, the species is likely widespread, but uncommon. ITS and LSU nrDNA sequences reveal that it forms a clade distant from that containing all previously known hygrophilous species. Comparisons with ecologically and morphologically similar species are also discussed. In particular, although its distinct grey colour recalls the terricolous A. griseopallida, the striate pileus is inconsistent with Desmazières’ protologue, and its morphological, ecological, and molecular features do not match any of the diverse modern interpretations of that name.

Asplundia capixaba (Cyclanthaceae), a new species from the Brazilian Atlantic Forest

EDUARDO S. LEAL — 2026-03-13

Cyclanthaceae (Pandanales) comprises 12 genera and approximately 230 species endemic to the Neotropical region, with its greatest diversity in northwestern South America and southern Central America. Brazil harbors 37 species of the family, most of them occurring in Amazonia. In contrast, the Atlantic Forest of eastern Brazil, despite being predominantly forested, the preferred environment for Cyclanthaceae, holds a lower species richness. Recent fieldwork in the Atlantic Forest of Espírito Santo state, combined with herbarium studies, revealed a set of specimens belonging to Asplundia, the richest genus of Cyclanthaceae, that does not match any described species. Thus, based on morphological evidence, we describe and illustrate Asplundia capixaba. We also discuss its affinities, provide notes on its distribution and ecology, and present a preliminary assessment of its conservation status as Endangered. We also provide an identification key for the Asplundia species from the Atlantic Forest, including Asplundia gardneri and A. rivularis, the species most closely related to the new taxon. This new discovery updates the knowledge of Cyclanthaceae in the Atlantic Forest and contributes to underscores the urgent need to conserve this biodiversity hotspot.

**New species of Ficus sect. Pharmacosycea (Moraceae) from the Andes and Coastal regions of Ecuador**

LEANDRO CARDOSO PEDERNEIRAS — 2026-03-13

Two new species of Ficus sect. Pharmacosycea subsect. Bergianae from Ecuador are described herein. The first, Ficus montalvoana, occurs at Andean elevations and, among other diagnostic characters such as velutinous leaves, exhibits a peduncle and receptacle significantly smaller than those of its related congener, Ficus dulciaria. The second species, Ficus penafieliae, occurs in western Ecuador and is distinguished by its glabrous leaves and geminate, sessile syconia, which are relatively small compared to those of its related congener, F. crassivenosa. Both species honor two renowned Ecuadorian researchers.