scholarly journals Ciguatoxin-Producing Dinoflagellate Gambierdiscus in the Beibu Gulf: First Report of Toxic Gambierdiscus in Chinese Waters

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 643
Author(s):  
Yixiao Xu ◽  
Xilin He ◽  
Wai Hin Lee ◽  
Leo Lai Chan ◽  
Douding Lu ◽  
...  
Keyword(s):  
Reef Fish ◽  
Phylogenetic Analyses ◽  
Morphological Characteristics ◽  
Small Subunit ◽  
Beibu Gulf ◽  
First Report ◽  
Chinese Waters ◽  
Rdna Sequences ◽  
Benthic Dinoflagellates ◽  
History Of

Ciguatera poisoning is mainly caused by the consumption of reef fish that have accumulated ciguatoxins (CTXs) produced by the benthic dinoflagellates Gambierdiscus and Fukuyoa. China has a long history of problems with ciguatera, but research on ciguatera causative organisms is very limited, especially in the Beibu Gulf, where coral reefs have been degraded significantly and CTXs in reef fish have exceeded food safety guidelines. Here, five strains of Gambierdiscus spp. were collected from Weizhou Island, a ciguatera hotspot in the Beibu Gulf, and identified by light and scanning electron microscopy and phylogenetic analyses based on large and small subunit rDNA sequences. Strains showed typical morphological characteristics of Gambierdiscus caribaeus, exhibiting a smooth thecal surface, rectangular-shaped 2′, almost symmetric 4′’, and a large and broad posterior intercalary plate. They clustered in the phylogenetic tree with G. caribaeus from other locations. Therefore, these five strains belonged to G. caribaeus, a globally distributed Gambierdiscus species. Toxicity was determined through the mouse neuroblastoma assay and ranged from 0 to 5.40 fg CTX3C eq cell−1. The low level of toxicity of G. caribaeus in Weizhou Island, with CTX-contaminated fish above the regulatory level in the previous study, suggests that the long-term presence of low toxicity G. caribaeus might lead to the bioaccumulation of CTXs in fish, which can reach dangerous CTX levels. Alternatively, other highly-toxic, non-sampled strains could be present in these waters. This is the first report on toxic Gambierdiscus from the Beibu Gulf and Chinese waters and will provide a basis for further research determining effective strategies for ciguatera management in the area.

scholarly journals First Report of Fusarium pernambucanum Causing Fruit Rot of Muskmelon in China

Plant Disease ◽  
2021 ◽  
Author(s):  
Xianping Zhang ◽  
Jiwen Xia ◽  
Jiakui Liu ◽  
Dan Zhao ◽  
Lingguang Kong ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Apical Cell ◽  
Morphological Characteristics ◽  
Fruit Rot ◽  
Likelihood Method ◽  
Correct Identification ◽  
Pathogenicity Test ◽  
First Report ◽  
The Core ◽  
Representative Isolate

Muskmelon (Cucumis melo L.) is one of the most widely cultivated and economically important fruit crops in the world. However, many pathogens can cause decay of muskmelons; among them, Fusarium spp. is the most important pathogen, affecting fruit yield and quality (Wang et al. 2011). In May 2017, fruit rot symptoms were observed on ripening muskmelons (cv. Jipin Zaoxue) in several fields in Liaocheng of Shandong Province, China. Symptoms appeared as brown, water-soaked lesions, irregularly circular in shape, with the lesion size ranging from a small spot (1 to 2 cm) to the decay of the entire fruit. The core and the surface of the infected fruit were covered with white to rose-reddish mycelium. Two infected muskmelons were collected from each of two fields, 10 km apart. Tissues from the inside of the infected fruit were surface disinfected with 75% ethanol for 30 s, and cultured on potato dextrose agar (PDA) at 25 °C in the dark for 5 days. Four purified cultures were obtained using the single spore method. On carnation leaf agar (CLA), macroconidia had a pronounced dorsiventral curvature, falcate, 3 to 5 septa, with tapered apical cell, and foot-shaped basal cell, measuring 19 to 36 × 4 to 6 μm. Chlamydospores were abundant, 5.5–7.5 μm wide, and 5.5–10.5 μm long, ellipsoidal or subglobose. No microconidia were observed. These morphological characteristics were consistent with the descriptions of F. pernambucanum (Santos et al. 2019). Because these isolates had similar morphology, one representative isolate was selected for multilocus phylogenetic analyses. DNA was extracted from the representative isolate using the CTAB method. The nucleotide sequences of the internal transcribed spacers (ITS) (White et al. 1990), translation elongation factor 1-α gene (TEF1), RNA polymerase II second largest subunit gene (RPB2), calmodulin (CAM) (Xia et al. 2019) were amplified using specific primers, sequenced, and deposited in GenBank (MN822926, MN856619, MN856620, and MN865126). Based on the combined dataset of ITS, TEF1, RPB2, CAM, alignments were made using MAFFT v. 7, and phylogenetic analyses were processed in MEGA v. 7.0 using the maximum likelihood method. The studied isolate (XP1) clustered together with F. pernambucanum reference strain URM 7559 (99% bootstrap). To perform pathogenicity test, 10 μl of spore suspensions (1 × 106 conidia/ml) were injected into each muskmelon fruit using a syringe, and the control fruit was inoculated with 10 μl of sterile distilled water. There were ten replicated fruits for each treatment. The test was repeated three times. After 7 days at 25 °C, the interior of the inoculated muskmelons begun to rot, and the rot lesion was expanded from the core towards the surface of the fruit, then white mycelium produced on the surface. The same fungus was re-isolated from the infected tissues and confirmed to fulfill the Koch’s postulates. No symptoms were observed on the control muskmelons. To our knowledge, this is the first report of F. pernambucanum causing of fruit rot of muskmelon in China. Considering the economic value of the muskmelon crop, correct identification can help farmers select appropriate field management measures for control of this disease.

scholarly journals First Report of Leaf Spot Disease Caused by Colletotrichum gloeosporioides on Chinese Bean Tree in China

Plant Disease ◽  
2013 ◽  
Vol 97 (1) ◽  
pp. 138-138 ◽  
Author(s):  
B. Z. Fu ◽  
M. Yang ◽  
G. Y. Li ◽  
J. R. Wu ◽  
J. Z. Zhang ◽  
...  
Keyword(s):  
Leaf Spot ◽  
Colletotrichum Gloeosporioides ◽  
Disease Incidence ◽  
Phylogenetic Analyses ◽  
Morphological Characteristics ◽  
Leaf Spot Disease ◽  
First Report ◽  
Spot Disease ◽  
Rdna Its ◽  
Its Sequence Analysis

Chinese bean tree, Catalpa fargesii f. duciouxii (Dode) Gilmour, is an ornamental arbor plant. Its roots, leaves, and flowers have long been used for medicinal purposes in China. During July 2010, severe outbreaks of leaf spot disease on this plant occurred in Kunming, Yunnan Province. The disease incidence was greater than 90%. The symptoms on leaves began as dark brown lesions surrounded by chlorotic halos, and later became larger, round or irregular spots with gray to off-white centers surrounded by dark brown margins. Leaf tissues (3 × 3 mm), cut from the margins of lesions, were surface disinfected in 0.1% HgCl2 solution for 3 min, rinsed three times in sterile water, plated on potato dextrose agar (PDA), and incubated at 28°C. The same fungus was consistently isolated from the diseased leaves. Colonies of white-to-dark gray mycelia formed on PDA, and were slightly brown on the underside of the colony. The hyphae were achromatic, branching, septate, and 4.59 (±1.38) μm in diameter on average. Perithecia were brown to black, globose in shape, and 275.9 to 379.3 × 245.3 to 344.8 μm. Asci that formed after 3 to 4 weeks in culture were eight-spored, clavate to cylindrical. The ascospores were fusiform, slightly curved, unicellular and hyaline, and 13.05 to 24.03 × 10.68 to 16.02 μm. PCR amplification was carried out by utilizing universal rDNA-ITS primer pair ITS4/ITS5 (2). Sequencing of the PCR products of DQ1 (GenBank Accession No. JN165746) revealed 99% similarity (100% coverage) with Colletotrichum gloeosporioides isolates (GenBank Accession No. FJ456938.1, No. EU326190.1, No. DQ682572.1, and No. AY423474.1). Phylogenetic analyses (MEGA 4.1) using the neighbor-joining (NJ) algorithm placed the isolate in a well-supported cluster (>90% bootstrap value based on 1,000 replicates) with other C. gloeosporioides isolates. The pathogen was identified as C. gloeosporioides (Penz.) Penz. & Sacc. (teleomorph Glomerella cingulata (Stoneman) Spauld & H. Schrenk) based on the morphological characteristics and rDNA-ITS sequence analysis (1). To confirm pathogenicity, Koch's postulates were performed on detached leaves of C. fargesii f. duciouxii, inoculated with a solution of 1.0 × 106 conidia per ml. Symptoms similar to the original ones started to appear after 10 days, while untreated leaves remained healthy. The inoculation assay used three leaves for untreated and six leaves for treated. The experiments were repeated once. C. gloeosporioides was consistently reisolated from the diseased tissue. C. gloeosporioides is distributed worldwide causing anthracnose on a wide variety of plants (3). To the best of our knowledge, this is the first report of C. gloeosporioides causing leaf spots on C. fargesii f. duciouxii in China. References: (1) B. C. Sutton. Page 1 in: Colletotrichum: Biology, Pathology and Control. CAB International. Wallingford, UK, 1992. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990. (3) J. Yan et al. Plant Dis. 95:880, 2011.

scholarly journals Ichthyobodo salmonis sp. n. (Ichthyobodonidae, Kinetoplastida), an euryhaline ectoparasite infecting Atlantic salmon (Salmo salar L.)

Parasitology ◽  
2011 ◽  
Vol 138 (9) ◽  
pp. 1164-1175 ◽  
Author(s):  
TROND E. ISAKSEN ◽  
EGIL KARLSBAKK ◽  
KUNINORI WATANABE ◽  
ARE NYLUND
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
Morphological Characteristics ◽  
Sensu Stricto ◽  
Ssu Rdna ◽  
Morphological Description ◽  
Rdna Sequences ◽  
Attachment Region

SUMMARYPhylogenetic analyses of SSU rDNA sequences have previously revealed the existence of 2 Ichthyobodo species able to infect Atlantic salmon (Salmo salar L.). Ichthyobodo necator sensu stricto (s.s.) is assumed to be a freshwater parasite, while a genetically distinct but undescribed species, Ichthyobodo sp. II sensu Todal et al. (2004) have been detected on Atlantic salmon in both fresh- and seawater. In the present study a morphological description of Ichthyobodo sp. II from the gills of salmon reared in fresh-, brackish- and seawater is presented, using both light- and electron microscopy. Comparative morphometry show that Ichthyobodo sp. II from both freshwater and seawater displays a different cell shape, and is significantly smaller than I. necator s.s. Also, ultrastructural characteristics distinguish these two species, notably differences in the attachment region and the presence of spine-like surface projections in Ichthyobodo sp. II. Based on both unique SSU rDNA sequences and morphological characteristics, we conclude that Ichthyobodo sp. II. represents a novel species for which we propose the name Ichthyobodo salmonis sp. n.

scholarly journals An SSU rDNA barcoding approach to the diversity of marine interstitial cercozoans, including descriptions of four novel genera and nine novel species

2010 ◽  
Vol 60 (8) ◽  
pp. 1962-1977 ◽  
Author(s):  
Chitchai Chantangsi ◽  
Brian S. Leander
Keyword(s):  
Novel Species ◽  
Phylogenetic Analyses ◽  
Environmental Dna ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Morphological Features ◽  
Molecular Signature ◽  
Nucleotide Sequence Analysis ◽  
Heterotrophic Flagellates ◽  
Rdna Sequences

Environmental DNA surveys have revealed a great deal of hidden diversity within the Cercozoa. An investigation into the biodiversity of heterotrophic flagellates in marine benthic habitats of British Columbia, Canada, demonstrated the presence of several undescribed taxa with morphological features that resemble the cercozoan genera Cryothecomonas and Protaspis. Nine novel species of marine interstitial cercozoans are described that are distributed into five genera, four of which are new. Phylogenetic analyses of small subunit rDNA sequences derived from two uncultured isolates of Protaspis obliqua and nine novel cercozoan species (within four novel genera) provided organismal anchors that helped establish the cellular identities of several different environmental sequence clades. These data, however, also showed that the rarity of distinctive morphological features in cryomonads, and other groups of cercozoans, makes the identification and systematics of the group very difficult. Therefore, a DNA barcoding approach was applied as a diagnostic tool for species delimitation that used a 618 bp region at the 5′ end of the SSU rDNA sequence. Nucleotide sequence analysis of this region showed high intergeneric sequence divergences of about 7 % and very low intraspecific sequence divergences of 0–0.5 %; phylogenetic analyses inferred from this barcoding region showed very similar tree topologies to those inferred from the full-length sequence of the gene. Overall, this study indicated that the 618 bp barcoding region of SSU rDNA sequences is a useful molecular signature for understanding the biodiversity and interrelationships of marine benthic cercozoans.

scholarly journals First Report of Fruit Rot Caused by Fusarium luffae in Muskmelon in China

Plant Disease ◽  
2022 ◽  
Author(s):  
Xianping Zhang ◽  
Xuedong Cao ◽  
Qingqing Dang ◽  
Yongguang Liu ◽  
Xiaoping Zhu ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Apical Cell ◽  
Morphological Characteristics ◽  
Fruit Rot ◽  
Likelihood Method ◽  
Correct Identification ◽  
Pathogenicity Test ◽  
Fusarium Spp ◽  
First Report ◽  
The Core

Muskmelon (Cucumis melo L.) is one of the most widely cultivated and economically important fruit crops in the world. However, many pathogens can cause decay of muskmelon fruit, including Fusarium spp.. Fusarium spp. are the most important pathogen, affecting muskmelon fruit yield and quality (Wang et al. 2011). In August 2020, fruit rot symptoms were observed on ripening muskmelons (cv. Tianbao) in several fields in Jiyang District, Jinan City of Shandong Province, China. The incidences of infected muskmelon ranged from 15% to 30% and caused an average 20% yield loss. Symptoms appeared as pale brown, water-soaked lesions that were irregular in shape, with the lesion sizes ranging from a small spot (1 to 2 cm) to decay of the entire fruit. The core and surface of infected fruit were colonized and covered with white mycelia. Two infected muskmelons were collected from two fields, 3.5 km apart. Tissues removed from inside the infected fruit were surface disinfected with 75% ethanol for 30 s, and cultured on potato dextrose agar (PDA) at 25°C in the dark for 5 days. Four purified cultures were obtained using the single spore method. On carnation leaf agar (CLA), 3 to 5 septate, falcate, with a pronounced dorsiventral curvature macroconidia with tapered apical cell, and foot-shaped basal cell, measuring 20 to 40 × 3.5 to 4.5 μm. Microconidia and chlamydospores were not observed. These morphological characteristics were consistent with the description of F. luffae (Wang et al., 2019). Because these isolates had similar morphology, two representative isolates (XP11 and XP12) were selected for multilocus phylogenetic analyses. DNA was extracted from the representative isolates using a CTAB method. Nucleotide sequences of the internal transcribed spacers (ITS) (White et al. 1990), calmodulin (CAM), RNA polymerase II second largest subunit (RPB2), translation elongation factor 1-α gene (TEF1) (Xia et al. 2019) were amplified using specific primers, sequenced, and deposited in GenBank (ITS: MW391509 and MW391510, CAM: MW392789 and MW392790, RPB2: MW392797 and MW392798, TEF1: MW392793 and MW392794). Alignments of a combined dataset of ITS, CAM, RPB2 and TEF1 were made using MAFFT v. 7, and phylogenetic analyses were conducted in MEGA v. 7.0 using the maximum likelihood method. The muskmelon isolates (XP11 and XP12) clustered together with the F. luffae reference strain LC12167 (99% bootstrap). To perform a pathogenicity test, 10 μl of conidial suspensions (1 × 106 conidia/ml) were injected into each muskmelon fruit using a syringe, and the control fruit was inoculated with 10 μl of sterile distilled water. There were ten replicated fruits for each treatment. The test was repeated three times. After 7 days at 25°C, the interior of the inoculated muskmelons begun to rot, and the rot lesion expanded from the core towards the surface of the fruit, then white mycelia were produced on the surface. Ten isolations were re-isolated from the infected tissues and confirmed to fulfill Koch’s postulates. No symptoms were observed on the control muskmelons. To our knowledge, this is the first report of fruit rot caused by F. luffae in muskmelon in China. Considering the economic value of the muskmelon crop, correct identification can help farmers select appropriate field management measures for control of this disease.

scholarly journals Four new species in the Tremella fibulifera complex (Tremellales, Basidiomycota)

MycoKeys ◽  
2021 ◽  
Vol 82 ◽  
pp. 33-56
Author(s):  
Long-Fei Fan ◽  
Renato Lúcio Mendes Alvarenga ◽  
Tatiana Baptista Gibertoni ◽  
Fang Wu ◽  
Yu-Cheng Dai
Keyword(s):  
New Species ◽  
Rna Polymerase Ii ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Elongation Factor ◽  
Morphological Characteristics ◽  
Molecular Data ◽  
Small Subunit ◽  
Molecular Evidence ◽  
Rrna Gene

Samples of species close to Tremella fibulifera from China and Brazil are studied, and T. fibulifera is confirmed as a species complex including nine species. Five known species (T. cheejenii, T. fibulifera s.s., T. “neofibulifera”, T. lloydiae-candidae and T. olens) and four new species (T. australe, T. guangxiensis, T. latispora and T. subfibulifera) in the complex are recognized based on morphological characteristics, molecular evidence, and geographic distribution. Sequences of eight species of the complex were included in the phylogenetic analyses because T. olens lacks molecular data. The phylogenetic analyses were performed by a combined sequence dataset of the internal transcribed spacer (ITS) and the partial nuclear large subunit rDNA (nLSU), and a combined sequence dataset of the ITS, partial nLSU, the small subunit mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α (TEF1), the largest and second largest subunits of RNA polymerase II (RPB1 and RPB2). The eight species formed eight independent lineages with robust support in phylogenies based on both datasets. Illustrated description of the six species including Tremella fibulifera s.s., T. “neofibulifera” and four new species, and discussions with their related species, are provided. A table of the comparison of the important characteristics of nine species in the T. fibulifera complex and a key to the whitish species in Tremella s.s. are provided.

scholarly journals Taxonomy and SSU rDNA-Based Phylogeny of Two Heterotrich Ciliates (Ciliophora, Heterotrichea) Collected From Subtropical Wetlands of China, Including the Description of a New Species, Linostomella pseudovorticella n. sp.

2021 ◽  
Vol 12 ◽  
Author(s):  
Didi Jin ◽  
Xuetong Zhao ◽  
Tingting Ye ◽  
Jie Huang ◽  
Alan Warren ◽  
...  
Keyword(s):  
New Species ◽  
Food Web ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Microbial Food Web ◽  
Model Organisms ◽  
Rdna Sequences ◽  
The Family ◽  
A New Species

The Heterotrichea Stein, 1859 are a group of ciliated protists (single-celled eukaryotes) that occur in a wide variety of aquatic habitat where they play important roles in the flow of nutrients and energy within the microbial food web. Many species are model organisms for research in cytology and regenerative biology. In the present study, the morphology and phylogeny of two heterotrich ciliates, namely, Linostomella pseudovorticella n. sp. and Peritromus kahli Villeneuve-Brachon, 1940, collected from subtropical wetlands of China, were investigated using morphological and molecular methods. L. pseudovorticella n. sp. differs from its only known congener, Linostomella vorticella Ehrenberg, 1833 Aescht in Foissner et al., 1999, by having more ciliary rows (48–67, mean about 56 vs. 26–51, mean about 42) and its small-subunit (SSU) rDNA sequence, which shows a 15-bp divergence. Although P. kahli has been reported several times in recent decades, its infraciliature has yet to be described. A redescription and improved diagnosis of this species based on a combination of previous and present data are here supplied. Phylogenetic analyses based on SSU rDNA sequences revealed that the genus Linostomella is positioned within Condylostomatidae, and Peritromidae is sister to Climacostomidae with relatively low support, and the family Spirostomidae is the root branch of the class Heterotrichea.

scholarly journals Multi-Gene Phylogeny and Taxonomy of Hydnellum (Bankeraceae, Basidiomycota) from China

2021 ◽  
Vol 7 (10) ◽  
pp. 818
Author(s):  
Yan-Hong Mu ◽  
Jia-Rui Yu ◽  
Ting Cao ◽  
Xiang-Hua Wang ◽  
Hai-Sheng Yuan
Keyword(s):  
New Species ◽  
Rna Polymerase Ii ◽  
Ribosomal Rna ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Morphological Characteristics ◽  
Small Subunit ◽  
Phylogenetic Position ◽  
Ribosomal Rna Gene ◽  
Morphological Studies

The genus Hydnellum is an important group of stipitate hydnaceous fungi which can form ectomycorrhiza with many species of woody plants. In recent decades, the frequency and number of basidiocarps observed in China have been declining significantly. So far, however, we know little about the species diversity of Hydnellum in China. In this study, we conducted molecular phylogenetic analyses based on sections of multiple loci, including the large subunit of nuclear ribosomal RNA gene (nLSU), the internal transcribed spacer regions (ITS), the small subunit of nuclear ribosomal RNA gene (SSU) and the second-largest subunit of RNA polymerase II gene (RPB2), as well as morphological studies, of collected samples of Hydnellum from China. We also inferred Maximum Likelihood and Bayesian phylogenies for the order Thelephorales from the dataset of the combined nLSU and ITS. This study has revealed the phylogenetic position of Hydnellum in the order Thelephorales, and phylogenetically confirmed ten major clades in Thelephorales; Twenty-nine taxa are proposed, described or reported, including 10 new subgenera (Hydnellum subgenus Hydnellum, subg. Caesispinosum, subg. Croceum, subg. Inflatum, subg. Rhizomorphum, subg. Scabrosum, subg. Spongiosum, subg. Subindufibulatum, subg. Violaceum and subg. Zonatum), 11 new species (Hydnellum atrorubrum, H. atrospinosum, H. bomiense, H. brunneorubrum, H. fibulatum, H. granulosum, H. inflatum, H. rubidofuscum, H. squamulosum, H. sulcatum and H. yunnanense), 3 newly recorded species (H. caeruleum, H. peckii and H. spongiosipes) and 5 notable specimens (Hydnellum sp 1, H. sp 2, H. sp 3, H. sp 4 and H. sp 5). A classification system based on the morphological characteristics (especially the hyphal structure types) and molecular analyses is proposed to accommodate most species in Hydnellum. The distinguishing characters of the subgenera and the new species with their closely related taxa are discussed. A key to the species of Hydnellum from China is provided.

Dothidea kunmingensis, a novel asexual species of Dothideaceae on Jasminum nudiflorum (winter jasmine) from Southwestern China

Phytotaxa ◽  
2021 ◽  
Vol 529 (1) ◽  
pp. 43-56
Author(s):  
YING GAO ◽  
JUTAMART MONKAI ◽  
ELENI GENTEKAKI ◽  
GUANG-CONG REN ◽  
DHANUSHKA N. WANASINGHE ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Elongation Factor ◽  
Morphological Characteristics ◽  
Small Subunit ◽  
Morphological Characterization ◽  
Small Subunit Rrna ◽  
Sister Relationship ◽  
Large Subunit Rrna

During a survey of saprobic microfungi in Southwest China, a coelomycetous fungus was found on dead twigs of Jasminum nudiflorum in Kunming, Yunnan Province. Based on a detailed morphological characterization coupled with multi-locus phylogenetic analyses, the fungus was identified as a new species in the genus Dothidea. Phylogenetic analyses using a combined matrix consisting of internal transcribed spacer (ITS), large subunit rRNA (LSU), small subunit rRNA (SSU), beta tubulin (tub2) and translation elongation factor-1 alpha (tef1-α) confirmed its placement in Dothideaceae and revealed a sister relationship to Dothidea eucalypti. The new species is characterized by pycnidial conidiomata, ampulliform or doliiform conidiogenous cells as well as aseptate, subglobose to ovoid, hyaline to pale-brown conidia. Comprehensive descriptions and illustrations are provided. Morphological characteristics of asexual morph taxa in Dothideaceae are also summarized and discussed.

Morphological reports on two species of Dexiotricha (Ciliophora, Scuticociliatia), with a note on the phylogenetic position of the genus

2014 ◽  
Vol 64 (Pt_2) ◽  
pp. 680-688 ◽  
Author(s):  
Xinpeng Fan ◽  
Saleh A. Al-Farraj ◽  
Feng Gao ◽  
Fukang Gu
Keyword(s):  
Phylogenetic Analyses ◽  
Eastern China ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Contractile Vacuole ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
North West ◽  
Rdna Sequences

Two Dexiotricha species (Dexiotricha elliptica nov. comb. and Dexiotricha cf. granulosa), respectively isolated from soil north-west of Riyadh, Saudi Arabia, and freshwater in Shanghai, eastern China, were investigated using standard methods. The species Loxocephalus ellipticus Kahl, 1931 is reclassified here in the genus Dexiotricha and was characterized mainly by constantly showing 16 somatic kineties, three post-oral kineties with the middle one shortened, a contractile vacuole located subcaudally with an excretory pore near the posterior end of somatic kinety 2 and single caudal cilia. A Dexiotricha granulosa-like organism having a subcaudally located contractile vacuole and fewer somatic kineties was designated D. cf. granulosa. The small-subunit rRNA gene (SSU rDNA) sequences of these two species were characterized and their phylogenetic positions based on SSU rDNA sequences were revealed by means of Bayesian inference and maximum-likelihood analysis. Phylogenetic analyses confirmed Dexiotricha as a monophyletic genus and supported its assignment to the order Loxocephalida. However, its family assignment remains unsupported.

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