Phytotaxa

**A taxonomic revision of Thaumatocaryon (Boraginaceae) reveals hidden diversity in southern South America**

Thu, 13 Aug 2026 00:00:00 +1200

Thaumatocaryon is a small genus of South American Boraginaceae with only three accepted names. This genus, along with Moritzia, comprises a monophyletic lineage called Moritziinae. During a review of herbarium specimens, we found morphological divergences that led us to conclude that Thaumatocaryon is more complex than previously known. According to the morphologic analysis, we recognize nine species, resulting from the revalidation of T. hilarii and the description of five new species. The species are differentiated by characteristics such as phyllotaxy, indumentum, as well as the length and color of the corolla, the morphology of stems and basal leaves, and the arrangement of flowering stems. We present a detailed description of each species, updating the four previously described species, field photographs (when available), exsiccate plates, distribution maps, and a key for all species of the genus.

**A new species and a new record of Phaeotremella (Phaeotremellaceae, Tremellales) from Brazil based on morphological and molecular data**

Thu, 13 Aug 2026 00:00:00 +1200

The genus Phaeotremella Rea was proposed in 1912 to accommodate Phaeotremella pseudofoliacea Rea. However, the proposal to establish this genus was not supported by the scientific community for over a century until the Tremellomycetes were restructured and the Phaeotremella folicae complex was defined based on molecular data. Currently, 23 species of Phaeotremella are known, most of which have been described in Eurasia, and a few species are known only from North America. Records for the Neotropical region are practically nonexistent. Therefore, the objective of this study was to identify the Phaeotremella specimens recently found in the Atlantic Forest, Southern and Southeastern Brazil. The specimens were collected in the mountainous regions of the states of Santa Catarina and Rio de Janeiro, and then subjected to morphological and molecular phylogenetic analyses. Phaeotremella frondosa is for the first time reported for the tropical region, in the Neotropics, and a new species, viz. Phaeotremella bicolorata, is described from Brazil.

**Redescription and re-evaluation of the extinction risk of Eugenia velutifolia Mazine & Sobral (Myrtaceae), an endemic shrub from the Cerrado of São Paulo state**

ISABELA PRESTES MARTINS, KARINNE SAMPAIO VALDEMARIN, FIORELLA FERNANDA MAZINE — Thu, 13 Aug 2026 00:00:00 +1200

Eugenia velutifolia Mazine & Sobral was described in 2019, based on specimens collected in Cerrado of São Paulo state. The species was evaluated as Critically Endangered (CR), occupying an Extent of Occurrence of 18,575 km². At the time of its description, its fruit and seed were unknown. This study aimed to expand the species' morphological record and reevaluate its conservation status. Therefore, field expeditions were carried out to the species' occurrence area to collect botanical material, and specimens already deposited in physical and digital herbaria were analyzed. Based on the collected data, the morphological description of the species was expanded to include characters of fruits, seeds, bracts, and bracteoles. Additionally, data regarding its ecology and interaction with local biodiversity were added, along with a reevaluation of the extinction risk of Eugenia velutifolia following IUCN criteria. Field efforts demonstrated that population located within Itu municipality has been suppressed; thus, E. velutifolia currently occurs only in the municipality of Salto de Pirapora, with a decrease in EOO to 0.027 km² and for AOO to 4 km², maintaining the CR status. The species' endemism, anthropic pressure, and low abundance of individuals highlight the need for conservation efforts.

**A new species of Phragmidium (Pucciniales, Phragmidiaceae) from Gansu, China**

YUN LIU, BAO-JIE CHI, JIN LIU, XIANG-LI YANG — Thu, 13 Aug 2026 00:00:00 +1200

This study reports Phragmidium gansuensis, a novel rust fungus species collected in Gansu Province, China, based on micromorphological characteristics and molecular data. This species is distinguished from morphologically similar taxa occurring on Rosa by its shorter teliospores with a length of 72–95 μm, longer pedicels, and an apical papilla. Phylogenetic analyses using combined ITS and LSU sequence data further supported the morphological identification.

Psammogeton udhampurensis sp. nov. (Apiaceae) from the Western Himalaya (India)

BACHAN LAL BHELLUM, RANI MAGOTRA — Thu, 13 Aug 2026 00:00:00 +1200

A new species of Psammogeton (Apiaceae) is described from the Western Himalaya, Jammu & Kashmir, India. The new taxon shows morphological affinity to P. biternatus and P. tyleri, but can be clearly distinguished by a combination of characters including peduncle length and articulation, bract morphology, number and markedly variable length of umbel rays, distinctly asymmetric umbels, number of flowers per umbellet, and schizocarp features. The species inhabits dry, hilly slopes at elevations of 800–1200 m a.s.l. A morphological description, diagnostic illustrations, and a comparative table with morphologically allied taxa are provided. Based on currently available data, the species appears to be narrowly endemic to the region and is provisionally assessed as Data Deficient (DD) following IUCN criteria.

Hoya sinagtala (Apocynaceae, Asclepiadoideae): A New, Unusual Species from the Philippines

SAMUEL C. BRILLO, DEREK D. CABACTULAN, MICHELE RODDA — Thu, 13 Aug 2026 00:00:00 +1200

Hoya sinagtala Brillo, Cabactulan & Rodda sp. nov. (Apocynaceae, Asclepiadoideae) from the Philippines is described. When sterile, it resembles several species of Hoya section Acanthostemma, but its flowers make it readily distinguishable by its rotate corolla with a narrowly campanulate tube and free-spreading lobes and triangular-ovate corona lobes. No other species in the genus exhibits this unique combination of characters. The species was originally collected from the wild in Samar Island and subsequently widely distributed in cultivation under the informal name Hoya sp. Samar GN 0003 and Hoya sp. “Yellow Sapphire”; it is herein formally published after nearly seven years of horticultural circulation.

Scutellaria guilinensis (Lamiaceae), a new species from northern Guangxi, China

JIN-XIN WEI, YING QIN — Thu, 13 Aug 2026 00:00:00 +1200

Scutellaria guilinensis (Lamiaceae), a new species from the limestone area in Guangxi, China is described and reported. The new species is similar to S. axilliflora and S. incisa in having pyramidal habit, solitary and axillary flowers, pedicel with 2 linear bracteoles, filaments pubescent at base, but it differs from the latter two by its some significantly arcuate internodes of stem, crenate margins of all blades, sparsely appressed puberulent calyx, pale purple-red corolla. The detailed information of the new species, including morphological descriptions, illustrations, etc. is provided here.