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imanr: An R Tool for the Identification of Mexican Native Maize Complexes
No full textThe conservation of the genetic diversity of native maize in Mexico is a priority due to its cultural, agricultural, and environmental importance. This study presents the development and evaluation of the imanr package, a computational tool based on Boosted Ensembles designed to automate the classification of racial complexes of native maize. Using a national database, a model was implemented that leverages morphological and geographical variables to provide precise and rapid classifications. The methodology included the optimization of key parameters through cross-validation, achieving up to 90% in balanced accuracy and a Cohen's Kappa coefficient of 0.84. These results highlight the robustness of the model compared to traditional methods, which rely on subjective expert judgment and require extended evaluation times. The findings demonstrate that the package not only surpasses conventional methods in terms of efficiency but also offers an accessible tool for conserving and monitoring native maize diversity, aligning with the recommendations of the Global Maize Project (PGMN). Moreover, its usability was enhanced by developing a graphical user interface, allowing non-specialized users to fully utilize its potential. imanr represents a significant advancement in native maize conservation science, contributing to the modernization of identification processes and strengthening sustainable management strategies for this essential genetic resource. This model directly addresses the need for innovative tools to monitor and preserve maize diversity in Mexico and suggests a promising pathway for future applications in the agricultural sector
Redescription of Papuanatula Lugo-Ortiz & McCafferty (Ephemeroptera, Baetidae), with description of a new subgenus and 20 new species
No full textMaterial from the type localities of most described species of Papuanatula and rich material newly collected across New Guinea and on the island Sulawesi form the bases for this comprehensive study of the genus, including the description of a new subgenus Papuafiliola subgen. nov. and 20 new species. Species delimitation is based on morphology of larvae and partly also imagos, supported by mitochondrial DNA data (COI) for some of the species. The total number of species is augmented from six to 26. The genus has a disjunct distribution on the islands New Guinea (incl. New Britain) and Sulawesi. A key to the larvae of all species is provided. Morphological similarities, the relationship of Papuanatula to other genera of Baetidae, and possible explanations for the high diversity in New Guinea are discussed
A new species of the genus Amolops (Anura, Ranidae) from the Gaoligong Mountains, China
No full textThe Gaoligong Mountains lie at the intersection of three global biodiversity hotspots. In recent years, with the continuous deepening of fieldwork in the region, studies have increasingly indicated that the amphibian diversity of this region remains poorly understood. During herpetological surveys in 2023, a series of Amolops specimens were collected from the Gaoligong Mountains of Yunnan Province, China. The integrated results of morphological and molecular phylogenetic analyses indicate the presence of a separate and previously unknown lineage in the A. viridimaculatus group, which we herein confirm as a new species, Amolops gudao Yu, Wu, Lu & Che, sp. nov. Our discovery increases the number of Amolops species recorded in China to 59, and the total number of Amolops species to 86. The discovery of a new species in the Gaoligong Mountains further highlights the underestimated amphibian diversity in the region, emphasizing the need for continued fieldwork and research. Furthermore, Amolops gudao Yu, Wu, Lu & Che, sp. nov. exhibits obvious intraspecific variation in color patterns, a phenomenon also reported in several species within the A. viridimaculatus group, such as A. viridimaculatus and A. kaulbacki. Future studies on the taxonomy of A. viridimaculatus group should be careful with the use of color patterns as a diagnostic characteristic
Resin outpourings on conifers are inhabited by more members of Nectriaceae (Hypocreales, Sordariomycetes) than previously thought
No full textResin outpourings on conifers are a quite unique habitat occurring in nature. Conifer resins are composed mainly from monoterpenes, sesquiterpenes and resin acids which are recalcitrant to microbial decomposition. Moreover, resins exhibit antimicrobial properties. Despite that, they are colonised by different microorganisms including fungi. They are called resinicolous fungi. They constitute a poorly explored group of the fungal kingdom. In this study, during investigation of resinicolous fungi in Poland, seven strains were assigned to the family Nectriaceae. Phylogenetic analyses of combined ITS, LSU, rpb2, tef1 and tub2 sequence data were used for molecular identification. As a result, two new species (including a new genus) and two known species were identified. Pulchrospora resinae gen. et sp. nov. and Cosmospora elegans sp. nov. were described, characterised and proposed herein. Known species such as Cosmospora viridescens and Cosmosporella pruni were isolated from resin substrate for the first time
Homatula gelao (Cypriniformes, Nemacheilidae), a new nemacheiline species of loach from the upper Yangtze River basin in Guizhou Province, southwestern China
No full textHomatula gelao, a new species, is here described from the Wu-Jiang of the Yangtze River basin in Guizhou province, southwestern China. This new species belongs to the elongate-bodied group of Homatula defined by having a complete lateral line, sparsely scales hidden in skin on the predorsal body, and a slender body with a uniform depth. It, along with H. variegata, is distinguished from all other species of this group in having a broadly rounded caudal fin and a small number of scales sparsely scattered over the predorsal body. Both differ in body coloration, striped pattern on the predorsal body, and caudal-peduncle length. The validity of the new species is corroborated by distinct genetic distance divergence with closely related congeneric species and its monophyly recovered in a mtDNA COI gene-based phylogenetic analysis. It is separated from other Homatula species by a minimum of 8.2% Kimura 2-parameter distance in the COI gene
Two new species of Ocotea (Lauraceae) with clustered leaves from the Uxpanapa region, Mexico
No full textTwo new species of Ocotea (Lauraceae) from Southern Mexico are described and illustrated. Based on their floral morphology, vegetative indument, and micromorphological attributes, both species are circumscribed within the Ocotea helicterifolia group. Within this clade, the two species are morphologically similar to those with clustered leaves. Both species are endemic to the species-rich yet fragmented forests of the Uxpanapa region in Mexico, and therefore, their populations are threatened. Here, the morphological similarities of both species and their conservation status are discussed
Tungsten wires with steel matrix composite: wetting and infiltration by steel melt
No full textLithium-based capillary porous systems (CPS) made of tungsten mesh are a part of the most prospective approach to plasma facing components. Currently, tungsten mesh as a part of the CPS is mounted directly on the experimental assembly without a proper joining with a substrate. Tungsten mesh filled with steel could be used as a base structure for the CPS. The experiment considers the wetting of tungsten by steel melt and the features of short- and long-term interaction between the two materials. Wetting was studied by improved sessile drop experiment. The results show that an average contact angle is 69° for SS316LN and 83.2° for SS420 melt on tungsten substrate with a temperature of 500–650 °C. Tungsten-steel composite was manufactured by infiltration of tungsten mesh with a steel melt. As a result of an active dissolution of tungsten in steel melt, (Fe,Cr)7W6 interaction layer with a thickness up to 10 µm forms around tungsten. Optimal structure with the thinnest intermetallic layer is obtained in the zones with the lowest temperature and the highest cooling speed
Global phylogeny of the family Gomphillaceae (Ascomycota, Graphidales) sheds light on the origin, diversification and endemism in foliicolous lineages
No full textFoliicolous lichens grow on living leaves of vascular plants. They are mostly found in tropical to subtropical or temperate rainforests. Many phenotype-based species are considered as pantropical or even sub-cosmopolitan, either attributed to old ages, having existed prior to continental breakups or long-distance dispersal. We built a much expanded, global phylogeny of Gomphillaceae, the most diverse group of leaf-dwelling lichenised fungi. Our sampling encompassed six major biodiversity hotspots: MIOI (Madagascar and the Indian Ocean Islands), the Caribbean, New Caledonia, the Colombian Chocó, Mesoamerica and the Atlantic coast of Brazil. It was based on multilocus sequence data (mtSSU rDNA, nuLSU rDNA and RPB1), including 2207 sequences of 1256 specimens. Species delimitation methods combined with a phenotype matrix identified 473 putative species. Amongst these, 104 are confirmed as described, 213 are classified as cryptic or near cryptic (hidden diversity), 100 represent new species to science (identified on the basis of phenotype) and 56 remain unidentified. Amongst the 104 species with a valid name, 40.5% are distributed across 2–5 continents (lichenogeographical regions) by applying the phenotype-based species concept. However, using the integrative approach to delineate species, this estimate is reduced to 9%. We estimate the global species richness of Gomphillaceae at 1,861–2,356 species. The timing of species-level divergences suggests that the current distribution of foliicolous lichens is shaped more by long-distance dispersal and rapid diversification than by vicariance. The origin of the family and major clades appears to be in the Neotropics, with subsequent numerous dispersal events. Our results support the separation of three major lineages, corresponding to the former families Asterothyriaceae, Gomphillaceae s.str. and Solorinellaceae, which should be recognised at the subfamily level
Fungal fairy rings: history, ecology, dynamics and engineering functions
No full textFungal fairy rings (FFR) are fascinating natural phenomena that have intrigued people and scientists for centuries. These patterns, often represented by circular distributions of altered vegetation, are found in grasslands and forest habitats. Fairy rings occur when fungi grow radially in the soil, raising from a central point, progressively degrading organic matter and thus affecting vegetation. The observation of such spatial patterns allows mycologists to conduct an in-depth analysis of the role of fungi in ecosystems. This review presents the current knowledge and scientific advancement of the studies of FFRs. An historical appraisal from the most representative pioneer studies until recent works is presented in different scientific fields, including microbiology, chemistry, botany and ecology. Based on a deep analysis of bibliographic data, we synopsised different aspects of FFRs: i) history of studies, ii) taxonomy, iii) ecology (environmental conditions and biogeography), iv) classification of vegetation patterns, v) spatial dynamics, vi) role as ecosystem engineer (impact on soil chemistry, plants and microbiota). In conclusion, beside still open research areas requiring further investigation, a schematic functional model of fungal fairy rings is proposed, in which on one hand the dynamics of the fungal mycelium is explained by self-DNA accumulation and the build-up of autotoxicity. On the other hand, the effects of fungi on plants are related to the intermingled and differently spatially distributed effects of hydrophobicity, phytotoxicity and phytostimulation
A new species of Gracixalus (Amphibia, Anura, Rhacophoridae) from Guizhou Province, China
No full textA new species of small tree frog was discovered in southwestern China, exhibiting morphological differences and molecular divergence. The new species, formally described herein as Gracixalus weii sp. nov., is morphologically distinct from other congeners by body size (SVL 30.1–34.0 mm in males and 35.2–36.0 mm in females). In addition, the head width was larger than the head length, with a distinct tympanum, a brown to beige dorsum, and an inversed Y-shaped dark brown marking. The skin of the dorsal and lateral surfaces of the head, body, and limbs was rough and sparsely scattered with tubercles. The toes showed moderately developed webbing, while finger webbing was rudimentary. Nuptial pads were found on the base of finger I; males had a single subgular vocal sac, with heels overlapping when the legs were at a right angle to the body, and the tibiotarsal articulation reached the mid-eye when the legs were stretched forward. Phylogenetic analyses based on DNA sequences of the mitochondrial 16S rRNA supported the new species as a sister species of G. jinxiuensis. Genetically, the new species diverges from its congeners by 3.4%–14.5% (uncorrected p-distance) and is closest to G. jinxiuensis, which is 3.4%