morphological comparison
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Phytotaxa ◽  
2022 ◽  
Vol 530 (3) ◽  
pp. 257-270
Author(s):  
MINH QUAN DANG ◽  
LEONID V. AVERYANOV ◽  
VAN SON DANG ◽  
TATIANA MAISAK ◽  
VAN HUONG BUI ◽  
...  

The paper presents a taxonomic review of Bulbophyllum section Rhytionanthos for the flora of Vietnam and provides the key for its species’ identification. A new species, B. truongtamii and a new variety, B. taeniophyllum var. denticulatoalatum are described for science. Bulbophyllum nodosum is reported for the first time from the country. Bulbophyllum strigosum, described 20 years ago based on cultivated plant of uncertain origin was rediscovered in NE Vietnam. For this species, location and detailed description are reported. Analytical photos, data on phenology, ecology, and distribution are presented for all studied species. The morphological comparison table of the new species, new variety and newly recorded species segregating them from similar species are presented.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0261682
Author(s):  
Somayeh Rasouli-Dogaheh ◽  
Jiří Komárek ◽  
Thomrat Chatchawan ◽  
Tomáš Hauer

Simple trichal types constitute a group of cyanobacteria with an abundance of novel, often cryptic taxa. Here, we investigated material collected from wet surface-soil in a saline environment in Petchaburi Province, central Thailand. A morphological comparison of the isolated strain with similar known species, as well as its phylogenetic and species delimitation analyses based on the combined datasets of other related organisms, especially simple trichal cyanobacteria, revealed that the material of this study represented an independent taxon. Using a multifaceted method, we propose that this material represents a new genus, Thainema gen. nov., belonging to the family Leptolyngbyaceae, with the type species Thainema salinarum sp. nov. This novel taxon shares similar ecological habitats with strains previously placed in the same lineage.


Phytotaxa ◽  
2022 ◽  
Vol 530 (1) ◽  
pp. 21-37
Author(s):  
LONG-LI LI ◽  
HONG-WEI SHEN ◽  
DanFeng Bao ◽  
YONG-ZHONG LU ◽  
HONG-YAN SU ◽  
...  

Diversity of lignicolous freshwater fungi in northwestern Yunnan, China is currently being studied. Four fresh collections of tubeufiaceous taxa were collected and identified. Among of them, Parahelicomyces yunnanensis sp. nov and Tubeufia nigroseptum sp. nov. are introduced as new species based on morphology and molecular phylogenetic analysis of combined ITS, SSU, TEF1-α and RPB2 sequence data. The detailed descriptions and illustrations of the new species are provided, as well as the morphological comparison with similar taxa are discussed. Two strains of Neohelicomyces aquaticus and Tubeufia cylindrothecia are provided.


2022 ◽  
pp. 107200
Author(s):  
Longfei Jiang ◽  
Jianpeng Zhang ◽  
Binye Chen ◽  
Shaoyu Zhang ◽  
Zihe Zhang ◽  
...  

Phytotaxa ◽  
2021 ◽  
Vol 529 (1) ◽  
pp. 71-85
Author(s):  
KAIO VINICIUS DE A. VIDAL ◽  
CASSIANO A. DORNELES WELKER ◽  
ALAÍSMA PEREIRA DA SILVA ◽  
ANA PAULA SANTOS-GONÇALVES ◽  
LYNN G. CLARK ◽  
...  

With 193 described species, Chusquea is the most diverse bamboo genus in the Neotropical region. Brazil, with 48 accepted species and 44 of them endemic, is one of its major centers of diversity. Among the Brazilian species, C. anelythra was only superficially characterized in its original publication almost 200 years ago, without a clear definition of its type-material, description of culm leaves, or comments on its geographic distribution or related species. As the absence of such information has greatly complicated the taxonomic delimitation of C. anelythra, the major aim of this paper is to clarify the identity of this species based on fieldwork and herbarium investigation, providing an emended description, illustrations, and photos of this species. We also designate a lectotype for the name C. anelythra, and provide a morphological comparison with two similar members of the C. meyeriana informal group. Geographic distribution and conservation status are also updated for this species.


2021 ◽  
Vol 7 (12) ◽  
pp. 1102
Author(s):  
Viridiana Magaña-Dueñas ◽  
José Francisco Cano-Lira ◽  
Alberto Miguel Stchigel

The Dothideomycetes are a class of cosmopolitan fungi that are present principally in terrestrial environments, but which have also been found in freshwater and marine habitats. In the present study, more than a hundred samples of plant debris were collected from various freshwater locations in Spain. Its incubation in wet chambers allowed us to detect and to isolate in pure culture numerous fungi producing asexual reproductive fruiting bodies (conidiomata). Thanks to a morphological comparison and to a phylogenetic analysis that combined the internal transcribed spacer (ITS) region of the nrDNA with fragments of the RNA polymerase II subunit 2 (rpb2), beta tubulin (tub2), and the translation elongation factor 1-alpha (tef-1) genes, six of those strains were identified as new species to science. Three belong to the family Didymellaceae: Didymella brevipilosa, Heterophoma polypusiformis and Paraboeremia clausa; and three belong to the family Phaeosphaeriaceae:Paraphoma aquatica, Phaeosphaeria fructigena and Xenophoma microspora. The finding of these new taxa significantly increases the number of the coelomycetous fungi that have been described from freshwater habitats.


2021 ◽  
Author(s):  
Bengt Ljungquist ◽  
Masood A Akram ◽  
Giorgio A Ascoli

Most functions of the nervous system depend on neuronal and glial morphology. Continuous advances in microscopic imaging and tracing software have provided an increasingly abundant availability of 3D reconstructions of arborizing dendrites, axons, and processes, allowing their detailed study. However, efficient, large-scale methods to rank neural morphologies by similarity to an archetype are still lacking. Using the NeuroMorpho.Org database, we present a similarity search software enabling fast morphological comparison of hundreds of thousands of neural reconstructions from any species, brain regions, cell types, and preparation protocols. We compared the performance of different morphological measurements: 1) summary morphometrics calculated by L-Measure, 2) persistence vectors, a vectorized descriptor of branching structure, 3) the combination of the two. In all cases, we also investigated the impact of applying dimensionality reduction using principal component analysis (PCA). We assessed qualitative performance by gauging the ability to rank neurons in order of visual similarity. Moreover, we quantified information content by examining explained variance and benchmarked the ability to identify occasional duplicate reconstructions of the same specimen. The results indicate that combining summary morphometrics and persistence vectors with applied PCA provides an information rich characterization that enables efficient and precise comparison of neural morphology. The execution time scaled linearly with data set size, allowing seamless live searching through the entire NeuroMorpho.Org content in fractions of a second. We have deployed the similarity search function as an open-source online software tool both through a user-friendly graphical interface and as an API for programmatic access.


2021 ◽  
Vol 12 ◽  
Author(s):  
Zuoying Wei ◽  
Zengqiang Xia ◽  
Jiangping Shu ◽  
Hui Shang ◽  
Stephen J. Maxwell ◽  
...  

Cryptic species comprise two or more taxa that are grounded under a single name because they are more-or-less indistinguishable morphologically. These species are potentially important for detailed assessments of biodiversity, but there now appear to be many more cryptic species than previously estimated. One taxonomic group likely to contain many cryptic species is Dicranopteris, a genus of forked ferns that occurs commonly along roadsides in Asia. The genus has a complex taxonomical history, and D. linearis has been particularly challenging with many intra-specific taxa dubiously erected to accommodate morphological variation that lacks clear discontinuities. To resolve species boundaries within Dicranopteris, we applied a molecular phylogenetic approach as complementary to morphology. Specifically, we used five chloroplast gene regions (rbcL, atpB, rps4, matK, and trnL-trnF) to generate a well-resolved phylogeny based on 37 samples representing 13 taxa of Dicranopteris, spanning the major distributional area in Asia. The results showed that Dicranopteris consists of ten highly supported clades, and D. linearis is polyphyletic, suggesting cryptic diversity within the species. Further through morphological comparison, we certainly erected Dicranopteris austrosinensis Y.H. Yan & Z.Y. Wei sp. nov. and Dicranopteris baliensis Y.H. Yan & Z.Y. Wei sp. nov. as distinct species and proposed five new combinations. We also inferred that the extant diversity of the genus Dicranopteris may result from relatively recent diversification in the Miocene based on divergence time dating. Overall, our study not only provided additional insights on the Gleicheniaceae tree of life, but also served as a case of integrating molecular and morphological approaches to elucidate cryptic diversity in taxonomically difficult groups.


Plant Disease ◽  
2021 ◽  
Author(s):  
Tao Zheng ◽  
Lin Zhao ◽  
Meng Ge Huang ◽  
Jian-Xin Deng ◽  
Yan Hui Wang

Oxalis corymbosa DC. introduced into China as an ornamental plant in the mid-19th century is commonly known as an important medicinal and edible perennial herb (Zhou et al. 2021). The plant native to South America is also an invasive and widely distributed weed found in agricultural farms, gardens, and lawns, especially in sugarcane fields of Guangxi province, China. The coverage rate of O. corymbosa in sugarcane fields was normally more than 70%, sometimes up to 100%. In March of 2021, a leaf spot disease of O. corymbosa from sugarcane fields was encountered in Nanning city of Guangxi province, China. Early symptoms appeared as small yellowish round spots. The spots turned to be irregularly, usually exhibiting pale brown necrosis in the center with dark brown necrotic well-defined margins. Severely infected leaves turned to be blighted, then dead. To isolate the pathogen, diseased leave tissue fragments (4 mm × 4 mm) were soaked in 75% ethanol for 10 s followed by 2% sodium hypochlorite for 1 min, and rinsed by sterile water for three times. They were transferred to potato dextrose agar (PDA) medium cultured at 25 °C. Pure cultures were obtained by collected hypha tip from upcoming colonies. The colony features were similar to each other, floccose, white at first, becoming brown, dark brown or black on PDA after 7 days fully covered the 90 mm petri-dishes. Conidial determination were conducted on synthetic nutrient-poor agar medium (SNA) according to Wang et al. (2017). Conidia abundantly dispersed on SNA arising from conidiophores, which normally reduced to conidiogenous cells generated from hyphae. The conidiogenous cells were monoblastic, hyaline, globose or ampulliform, 6–8.5 (–12.5) × 5–7.5 (–9) μm in size (n=50). Conidia were solitary, smooth, black, sphaerical or ellipsoidal, (11–) 13–16.5 × (8–) 10–15.5 μm in size (n=100). Setae were not observed during the observation. The fungus was identified as Nigrospora sp. based on the morphology. One of the representative strains (FSC-3) was selected for genomic DNA extraction. The sequences of transcribed spacer region of rDNA (ITS), the partial translation elongation factor (TEF1), and the Beta-tubulin fragment (TUB) were respectively amplified using primer pairs ITS1/ITS4 (White et al. 1990), EF1-728F and EF2 (Carbone & Kohn 1999, Crous et al. 2013) and Bt2a and Bt2b (Glass & Donaldson 1995), deposited in the NCBI GenBank with accession numbers of OK083685 (541 bp), OK184809 (481 bp) and OK086377 (421 bp). BLASTn analysis showed that those ITS, TEF1 and TUB gene sequences shared 99%-100% identity with the type strain (CGMCC3.18129) of Nigrospora hainanensis (GenBank accession nos. NR153480, KY019415, KY019464, respectively). In addition, a maximum likelihood analysis using concatenated gene sequences of ITS, TEF1 and TUB was performed in RAxML v.7.2.8 (Stamatakis 2006) implementing the model of GTRCAT with 1,000 bootstrap replicates. The phylogenetic results indicated that the strain FSC-3 was N. hainanensis, which also confirmed after a morphological comparison with N. hainanensis (Wang et al. 2017). Pathogenicity was tested on living Oxalis corymbosa leaves (3 plants for each test) arising from cultivated roots grown for three weeks. It was conducted by dropping 5 μL conidial suspensions (105 conidia / mL) on the living leaves (two sites per leave) incubated in separate containers at 25 °C with 90-100% relative humidity after inoculation. Controls were treated with sterile distilled water. Pale brown small spots came up after 24 h, and then extended to brown larger spots. Symptoms after inoculation were similar to field ones, while the control plants remained healthy. The pathogenicity test was repeated twice with the similar results. Re-isolation of the pathogen from the inoculated leaves was determined based on morphology and sequence analysis to fulfill Koch's postulates. Nigrospora hainanensis had been found from diseased root and leaf tissues of sugarcane in Liuzhou city, Guangxi province (Raza et al. 2019). The results indicated that O. corymbosa was another host in sugarcane fields in Guangxi, China. To our knowledge, this is the first report of Nigrospora hainanensis causing leaf spot on Oxalis corymbosa in China.


PhytoKeys ◽  
2021 ◽  
Vol 187 ◽  
pp. 71-76
Author(s):  
Zhi-Yong Xiao ◽  
Xiao-Chun Li ◽  
Ying Luo ◽  
Chuan-Sheng Zeng ◽  
Bang-Gui Qiu ◽  
...  

Vicia mingyueshanensis, a new species from the Mingyue Mountain Region of western Jiangxi, China, is described and illustrated. It is a perennial climbing liana that always links to riparian woods. A morphological comparison indicated that the new species is closely similar to Vicia taipaica K. T. Fu and Vicia dichroantha Diels; however, it differs from the other two species by several salient characters, such as plant indumentum, stipule shape, corolla colour, bractlet shape and calyx shape. Photographs, a preliminary conservation assessment, table of morphological characters and distribution map comparing this new species to two morphologically-similar species are also provided.


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