Phytotaxa

Introducing one new genus and two new species of Psathyrellaceae (Basidiomycota, Agaricales), with notes on Candolleomyces and Ephemerocybe

2025-04-22T16:28:46+12:00

During an investigation on psathyrelloid fungi conducted from 2023 to 2024 in the Pearl River Delta in South China, 49 collections were gathered and studied through morphological observations and phylogenetic analyses. Among these collections, eight are identified as a new species of a new genus, namely Cantonopsathyra serendipita, characterized by terrestrial psathyrelloid basidiomata with a slightly rugose pileus, basidiospores with an irregularly wrinkled surface, and the rare presence of pleurocystidia and clamp connections; two are identified as a new species of Parasola, namely Pa. haizhuensis, characterized by lignicolous psathyrelloid basidiomata with an undulate pileus margin; while the remaining 39 could only be identified to the generic level of Candolleomyces. Species delimitation within Candolleomyces is found to be challenging, because the following problems often occur in the hypothetical species on our ITS phylogeny: (1) with an ITS sequence more than 99% similar to that of another species; (2) issued by a very short branch from the backbone; (3) unsupported by statistical values; (4) not a monophyletic group; and (5) with inaccurate sequences. A four-locus (ITS, nrLSU, tef-1α, and β-tub) phylogenetic analysis with limited samples of Candolleomyces appears to alleviate most of these problems by providing clearer partitions; however, four-locus data for previously proposed species remain largely unavailable for comparison. Based on the recent scale of species delimitation in Candolleomyces, more than ten new species of Candolleomyces appear to exist in our collections; however, due to the aforementioned issues, they are not formally proposed in this study. We recommend that new species of Candolleomyces proposed in the future should be provided with four-locus data of ITS, nrLSU, tef-1α, and β-tub. Supplementary sequencing for unprovided loci from type materials of previously proposed Candolleomyces species, particularly those proposed in recent years, is also highly encouraged. The recently proposed genus Tulosesus is illegitimate due to its circumscription including the type of an earlier legitimate genus, Ephemerocybe, and corresponding new combinations for transfer are made. Another genus, Lacrymaria Pat. 1887, is also illegitimate due to the homonymy with an earlier protist genus, Lacrymaria Ehrenberg 1830, but may be worth conserving; therefore, it is not treated here.

Pimpinella husnucan-baseri (Apiaceae), a new species from South Anatolia, Turkey

2025-01-09T22:11:26+13:00

In this study, we describe Pimpinella husnucan-baseri (Apiaceae) as a new species from South Anatolia. It grows in serpentine places in the district of Hadim (Konya province). Morphological data and molecular phylogenetic analysis indicate affinities of the new species with Pimpinella, in spite of its anomalous features within the genus. Pimpinella husnucan-baseri is a distinct species with no close relatives, and it differs from all other species in the genus with respect to its very long and horizontal-ascending branches, mostly radical leaves, 2–3-pinnate, cauline leaves dissimilar to basal leaves, absent bracts and bracteoles, glabrous petals and ovary, hemispherical-depressed stylopodium, broadly ovate and glabrous fruits; dorsal vittae 5–12 per vallecula, 30–35 in total. The anatomical structure of the fruit is documented and the geographical distribution of the new species is mapped. The habitat, ecology, phenology, and conservation status of the new species are also provided.

**A new spider-pathogenic species Gibellula liaoningensis (Cordycipitaceae) from Liaoning Province, China**

2025-02-17T20:14:53+13:00

Gibellula species are obligate parasites of spider, gaining extensive attention upon their taxonomy. In this study, we describe Gibellula liaoningensis sp. nov. based on morphological characteristics and molecular evidence. The multi-locus phylogenetic analyses using six molecular markers (SSU, LSU, ITS, TEF-1α, RPB1, and RPB2) robustly resolved its phylogenetic distinctiveness within the genus. Morphologically, G. liaoningensis is characterized by penicillate conidiophores exhibiting a significantly shortened stipe and clavate conidia. This taxon represents the first recorded Gibellula species in the Northeast China region, expanding the known geographic distribution of this ecologically specialized fungal genus.

Senna hatschbachii (Leguminosae, Caesalpinioideae): a newly discovered endangered species from the Brazilian Atlantic Forest

2025-02-11T02:38:33+13:00

Senna hatschbachii, a new species of Senna sect. Peiranisia ser. Interglandulosae, is endemic to Brazil and occurs in the Atlantic Forest of northern Paraná State. The species is described and illustrated here employing traditional taxonomic criteria based on collections from Brazilian herbaria. Morphologically, Senna hatschbachii is closely related to Senna multijuga var. lindleyana, although it differs by having linear stipules ≤ 0.1 mm wide, a subulate extrafloral nectary between the first pair of leaflets, and leaves with 6–13 pairs of leaflets (vs. setiform stipules with 0.2–0.4 mm wide, an ovoid to narrow-ovoid extrafloral nectary located between the first pair of leaflets and occasionally between subsequent pairs, and leaves with 15–46 pairs of leaflets in S. multijuga var. lindleyana). Its morphological and anatomical traits, identification key, geographic distribution, and habitat are discussed, along with a preliminary conservation assessment following IUCN Red List guidelines. In addition, we also provide a key for identifying tree taxa of Senna ser. Interglandulosae in Brazil.

Onosma sanninensis (Boraginaceae), a new species from the Mount Sannine Central Lebanon

2025-03-13T01:59:47+13:00

In this study, a new species of Onosma (Boraginaceae: Lithospermeae), subsect. Asterotricha, from Mount Sannine, Lebanon, is described and illustrated. This new species was conclusively identified through a comprehensive analysis of morphological features and geographical distributions compared across herbarium specimens from multiple collections. The new species is closely related to O. caerulescens and O. inexspectata, but it is different with 1–2 terminal cymes, smaller bracts, longer pedicels in fruit, larger calyx in flower and fruit, different corolla color, smaller anthers, and different pollen shape. Additionally, geographical distributions and map, an image of the holotype specimen, diagnostic characters, detailed photographs, habitat descriptions, and an identification key for the new species, O. caerulescens, and O. inexspectata are provided, along with a vernacular name and IUCN conservation status.

**Rediscovery of Sicydium nereoi (Cucurbitaceae), a critically endangered micro-endemic of riverine islands in Esquina, northeastern Argentina, with details on morphology, ecology, and conservation**

2025-04-24T20:36:37+12:00

This study provides a comprehensive morphological description and updated information of Sicydium nereoi, a microendemic climbing species of Cucurbitaceae, rediscovered in the riparian islands of Esquina, Corrientes, Argentina, after 50 years of being known only from the type specimen. We document for the first time the morphology of the pistillate flowers, fruits, and seeds, which differ from other Sicydium species by their ovoid, fleshy fruits, densely pubescent ovary, and glandular trichomes. A total of thirty-four individuals were recorded in three populations, restricted to an area of occupancy of 8 km² on organic-rich, calcareous soils. Based on IUCN criteria, we assign S. nereoi to the Critically Endangered (CR) category due to its limited distribution, small population size, and threats from habitat degradation and land use change. These findings provide key insights into the species’ morphological distinctiveness, ecological niche, and urgent conservation needs.

Orinoquia brasiliensis (Apocynaceae, Asclepiadoideae), a new endemic species and the first record of the genus in Brazil

2024-09-20T18:43:39+12:00

A new species of Orinoquia (Gonolobinae, Apocynaceae) from the state of Mato Grosso, in the Central-West region of Brazil is described and illustrated, making this the first record of this genus in the country. Orinoquia brasiliensis is morphologically similar to O. yanomamica, which is known to occur only in Venezuela, but differs mainly by branches only with long simple trichomes, longer pedicels and sepals, and ovate corolla lobes; the follicles of the genus are here described for the first time. The new species is endemic to the Cerrado and known from only one population; therefore, its conservation status is suggested as Data Deficient (DD), according to IUCN criteria. A distribution map with the occurrence of the two known Orinoquia species is presented, as well as taxonomic comments, images, an illustration, a comparative table with the main features to distinguish the genus, and an identification key to the Gonolobinae of Mato Grosso.

Erysiphe jiangxiensis sp. nov. associated with powdery mildew on Castanopsis sclerophylla in Jiangxi, China

2025-04-21T01:04:03+12:00

Between 2020 and 2023, Castanopsis sclerophylla, an evergreen broad-leaved tree native to southern China, exhibited powdery mildew symptoms on mature trees in Nanchang, Jiangxi province, with an incidence rate of 50% to 75%. Microscopic examination of the sexual morph revealed that the fungus differed from Erysiphe kissiana by having smaller chasmothecia, and fewer asci and ascospores. These findings were supported by maximum likelihood analysis and Bayesian inference, which showed low bootstrap support and Bayesian posterior probabilities. Based on morphological differences and molecular phylogenetic analysis, we identified this fungus as a new species, Erysiphe jiangxiensis. The pathogenicity of E. jiangxiensis on C. sclerophylla was confirmed using modified Koch’s postulates. The discovery of E. jiangxiensis has significant implications for identifying powdery mildew species on Chinese tanbark-oak and for disease management.

Japewiella jingningensis (Lecanoraceae), a new species from China

2024-10-02T09:32:29+13:00

Japewiella jingningensis is a species new to science from China. It is characterized by its thin, smooth, slightly rimose crustose thallus, a red-brown to olive-brown epihymenium, small ascospores 12–13.5 × 5.5–7 μm, and containing an unknown chemical metabolite (bluish fluorescence in UV after the acid/heat treatment). Species identification is based on morphology, anatomy, chemistry, and phylogenetic analyses, which reveals its definitive taxonomic position. Detailed taxonomic descriptions, ecological and chemical characters, and illustrations are provided for the new species. A key to the species of genus Japewiella is also provided.

Erratum: HENG PAN, YI WANG, GANG TAO & ZHI-YUAN ZHANG (2025) Morphological and phylogenetic characterisation of Podospora sichuanensis sp. nov. (Podosporaceae, Sordariales). Phytotaxa 695 (1): 123–130.

2025-05-22T10:28:28+12:00

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