scholarly journals A novel histozoic myxosporean, Enteromyxum caesio n. sp., infecting the redbelly yellowtail fusilier, Caesio cuning, with the creation of the Enteromyxidae n. fam., to formally accommodate this commercially important genus

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9529
Author(s):  
Mark A. Freeman ◽  
Tetsuya Yanagida ◽  
Àrni Kristmundsson

Gastrointestinal myxosporean parasites from the genus Enteromyxum are known to cause severe disease, resulting in high mortalities in numerous species of cultured marine fishes globally. Originally described as Myxidium spp., they were transferred to a new genus, Enteromyxum, to emphasize their novel characteristics. Their retention in the family Myxidiidae at the time was warranted, but more comprehensive phylogenetic analyses have since demonstrated the need for a new family for these parasites. We discovered a novel Enteromyxum in wild fish from Malaysia and herein describe the fourth species in the genus and erect a new family, the Enteromyxidae n. fam., to accommodate them. Enteromyxum caesio n. sp. is described infecting the tissues of the stomach in the redbelly yellowtail fusilier, Caesio cuning, from Malaysia. The new species is distinct from all others in the genus, as the myxospores although morphologically similar, are significantly smaller in size. Furthermore, small subunit ribosomal DNA sequence data reveal that E. caesio is <84% similar to others in the genus, but collectively they form a robust and discrete clade, the Enteromyxidae n. fam., which is placed as a sister taxon to other histozoic marine myxosporeans. In addition, we describe, using transmission electron microscopy, the epicellular stages of Enteromyxum fugu and show a scanning electron micrograph of a mature myxospore of E. caesio detailing the otherwise indistinct sutural line, features of the polar capsules and spore valve ridges. The Enteromyxidae n. fam. is a commercially important group of parasites infecting the gastrointestinal tract of marine fishes and the histozoic species can cause the disease enteromyxosis in intensive finfish aquaculture facilities. Epicellular and sloughed histozoic stages are responsible for fish-to-fish transmission in net pen aquaculture systems but actinospores from an annelid host are thought to be necessary for transmission to fish in the wild.

2021 ◽  
Vol 12 ◽  
Author(s):  
Chen Shao ◽  
Qi Gao ◽  
Alan Warren ◽  
Jingyi Wang

The morphology and the regulation of cortical pattern associated with the cell size, division, and phylogenetic position of a new hypotrichous ciliate, Quadristicha subtropica n. sp. collected from a freshwater pond in southern China, were investigated. Quadristicha subtropica n. sp. is characterized as follows: size in vivo 60–115 μm × 25–45 μm; 19–21 adoral membranelles; buccal cirrus near anterior end of endoral and paroral; cirrus IV/3 at about level of buccal vertex; right marginal row begins ahead of buccal vertex; 11–16 right and 12–19 left marginal cirri; and dorsal cilia about 5 μm long. The basic morphogenetic process in Q. subtropica n. sp. is consistent with that of the type species, Quadristicha setigera. Phylogenetic analyses based on small subunit ribosomal DNA sequence data reveal that the systematic position of Q. subtropica n. sp. is rather unstable with low support values across the tree and the genus Quadristicha is not monophyletic.


2019 ◽  
Vol 42 (1) ◽  
pp. 228-260 ◽  
Author(s):  
H. Voglmayr ◽  
M.B. Aguirre-Hudson ◽  
H.G. Wagner ◽  
S. Tello ◽  
W.M. Jaklitsch

Based on DNA sequence data, the genus Leptosillia is shown to belong to the Xylariales. Molecular phylogenetic analyses of ITS-LSU rDNA sequence data and of a combined matrix of SSU-ITS-LSU rDNA, rpb1, rpb2, tef1 and tub2 reveal that the genera Cresporhaphis and Liberomyces are congeneric with Leptosillia. Coelosphaeria fusariospora, Leptorhaphis acerina, Leptorhaphis quercus f. macrospora, Leptorhaphis pinicola, Leptorhaphis wienkampii, Liberomyces pistaciae, Sphaeria muelleri and Zignoëlla slaptonensis are combined in Leptosillia, and all of these taxa except for C. fusariospora, L. pinicola and L. pistaciae are epitypified. Coelosphaeria fusariospora and Cresporhaphis rhoina are lectotypified. Liberomyces macrosporus and L. saliciphilus, which were isolated as phloem and sapwood endophytes, are shown to be synonyms of Leptosillia macrospora and L. wienkampii, respectively. All species formerly placed in Cresporhaphis that are now transferred to Leptosillia are revealed to be non-lichenized. Based on morphology and ecology, Cresporhaphis chibaensis is synonymised with Rhaphidicyrtis trichosporella, and C. rhoina is considered to be unrelated to the genus Leptosillia, but its generic affinities cannot be resolved in lack of DNA sequence data. Phylogenetic analyses place Leptosillia as sister taxon to Delonicicolaceae, and based on morphological and ecological differences, the new family Leptosilliaceae is established. Furfurella, a new genus with the three new species, F. luteostiolata, F. nigrescens and F. stromatica, growing on dead branches of mediterranean fabaceous shrubs from tribe Genisteae, is revealed to be the closest relative of Delonicicola in the family Delonicicolaceae, which is emended. ITS rDNA sequence data retrieved from GenBank demonstrate that the Leptosilliaceae were frequently isolated or sequenced as endophytes from temperate to tropical regions, and show that the genus Leptosillia represents a widely distributed component of endophyte communities of woody plants.


Phytotaxa ◽  
2016 ◽  
Vol 275 (2) ◽  
pp. 97 ◽  
Author(s):  
TODD G.B. McLAY ◽  
MICHAEL J. BAYLY

Chamaescilla is an endemic Australian genus, currently placed in the Asparagaceae, alongside other Australian endemic taxa in the tribe Lomandroideae. A recent molecular phylogeny indicated a relationship with another partly Australian family, the Xanthorrhoeaceae, but was not commented on by the authors. Here we added DNA sequence data for a single Chamaescilla specimen to an alignment representing all families in the Asparagales and performed parsimony and Bayesian phylogenetic analyses. Chamaescilla was strongly resolved as belonging to Xanthorrhoeaceae, subfamily Hemerocallidoideae, alongside two non-Australian members, Simethis and Hemerocallis in the hemerocallid clade. This position is corroborated by morphological characters, including pollen grain shape. We also produced an age-calibrated phylogeny and infer that the geographic distribution of the clade is the result of long distance dispersal between the Eocene and Miocene.


Phytotaxa ◽  
2014 ◽  
Vol 176 (1) ◽  
pp. 184 ◽  
Author(s):  
Huang Zhang ◽  
Kevin D. Hyde ◽  
Yongchang Zhao ◽  
ERIC H.C. MCKENZIE ◽  
Dequn Zhou

Lophiostoma vaginatispora comb. nov. was collected from submerged wood in a stream in Northern Thailand. The species is characteristic by immersed to erumpent ascomata, with slot-like ostioles, with long, branched and numerous periphyses, an unequally thick peridium where the upper part is narrower than the lower part, and 1-septate, narrowly fusiform ascospores with a thick surrounding papilionaceous sheath. The placement of this species in Lophiostoma is based on morphological characters and phylogenetic analyses of the partial nuclear ribosomal 18S small subunit and 28S large subunit DNA sequence data. Lophiostoma vaginatispora is distinguished from other Lophiostoma species in possessing a wide papilionaceous sheath.


2021 ◽  
Vol 9 (3) ◽  
pp. 666
Author(s):  
Niccolò Forin ◽  
Alfredo Vizzini ◽  
Federico Fainelli ◽  
Enrico Ercole ◽  
Barbara Baldan

In a recent monograph on the genus Rosellinia, type specimens worldwide were revised and re-classified using a morphological approach. Among them, some came from Pier Andrea Saccardo’s fungarium stored in the Herbarium of the Padova Botanical Garden. In this work, we taxonomically re-examine via a morphological and molecular approach nine different Roselliniasensu Saccardo types. ITS1 and/or ITS2 sequences were successfully obtained applying Illumina MiSeq technology and phylogenetic analyses were carried out in order to elucidate their current taxonomic position. Only the ITS1 sequence was recovered for Rosellinia areolata, while for R. geophila, only the ITS2 sequence was recovered. We proposed here new combinations for Rosellinia chordicola, R. geophila and R. horridula, while for R. ambigua, R. areolata, R. australis, R. romana and R. somala, we did not suggest taxonomic changes compared to the current ones. The name Rosellinia subsimilis Sacc. is invalid, as it is a later homonym of R. subsimilis P. Karst. & Starbäck. Therefore, we introduced Coniochaeta dakotensis as a nomen novum for R. subsimilis Sacc. This is the first time that these types have been subjected to a molecular study. Our results demonstrate that old types are an important source of DNA sequence data for taxonomic re-examinations.


2015 ◽  
Vol 65 (Pt_9) ◽  
pp. 3216-3225 ◽  
Author(s):  
Xiaoteng Lu ◽  
Chen Shao ◽  
Yuhe Yu ◽  
Alan Warren ◽  
Jie Huang

The oxytrichid species Pleurotricha curdsi (Shi et al., 2002) Gupta et al., 2003, isolated from a tributary of the Yangtze River in the Mudong district of Chongqing, southern China, was reinvestigated with emphasis on its morphology, morphogenesis and small-subunit (SSU) rDNA-based phylogeny. Compared with three previously described populations, the Mudong population of P. curdsi is characterized by its large body size, 170–295 × 65–110 μm in vivo, and by having a variable number of right marginal rows, either two or three. Likewise, the number of right marginal rows anlagen (RMA) is also variable, i.e. usually two, but sometimes several small extra anlagen that give rise to the formation of the third row, are present to the left of the RMAs. We posit that the Mudong population is an intermediate form between the three previously described populations. Phylogenetic analyses based on the SSU rDNA sequence data show that all populations of P. curdsi cluster with the type species of the genus, Pleurotricha lanceolata, in a clade nested within the Oxytrichidae.


Plant Disease ◽  
2003 ◽  
Vol 87 (11) ◽  
pp. 1329-1332 ◽  
Author(s):  
J. Roux ◽  
H. Myburg ◽  
B. D. Wingfield ◽  
M. J. Wingfield

Cryphonectria cubensis is an economically important pathogen of commercial Eucalyptus spp. Differences have been reported for disease symptoms associated with Cryphonectria canker in South Africa and other parts of the world, and recent DNA-based comparisons have confirmed that the fungus in South Africa is different from that in South America and Australasia. During a disease survey in the Republic of Congo, Cryphonectria canker was identified as an important disease on Eucalyptus grandis and E. urophylla. In this study, we compared Congolese and South African isolates of C. cubensis using DNA sequence data and pathogenicity under greenhouse conditions. The β-tubulin and internal transcribed spacer (ITS) region sequences show that C. cubensis in Congo is different from the fungus in South Africa and that Congolese isolates group most closely with South American isolates. Furthermore, pathogenicity tests showed that a South African isolate was more aggressive than two Congolese isolates. We conclude that two distinct Cryphonectria spp. occur in Africa and hypothesize that the fungus in the Congo probably was introduced into Africa from South America. Both fungi are important pathogens causing disease and death of economically important plantation trees. However, they apparently have different origins and must be treated separately in terms of disease management and quarantine considerations.


2017 ◽  
Vol 31 (6) ◽  
pp. 781 ◽  
Author(s):  
Savel R. Daniels ◽  
Megan Dreyer ◽  
Prashant P. Sharma

During the present study, we examined the phylogeography and systematics of two species of velvet worm (Peripatopsis Pocock, 1894) in the forested region of the southern Cape of South Africa. A total of 89 P. moseleyi (Wood-Mason, 1879) and 65 P. sedgwicki (Purcell, 1899) specimens were collected and sequenced for the cytochrome c oxidase subunit I mtDNA (COI). In addition, a single P. sedgwicki specimen per sample locality was sequenced for the 18S rRNA locus. Furthermore, morphological variation among P. sedgwicki sample localities were explored using traditional alpha taxonomic characters. DNA sequence data were subjected to phylogenetic analyses using Bayesian inference and population genetic analyses using haplotype networks and analyses of molecular variance (AMOVAs). Phylogenetic results revealed the presence of four and three clades within P. moseleyi and P. sedgwicki respectively. Haplotype networks were characterised by the absence of shared haplotypes between clades, suggesting genetic isolation, a result corroborated by the AMOVA and highly significant FST values. Specimens from Fort Fordyce Nature Reserve were both genetically and morphologically distinct from the two remaining P. sedgwicki clades. The latter result suggests the presence of a novel lineage nested within P. sedgwicki and suggests that species boundaries within this taxon require re-examination.


2021 ◽  
Vol 12 ◽  
Author(s):  
Qi Gao ◽  
Chen Shao ◽  
Qiuyue Tang ◽  
Jingbao Li

The morphology and morphogenesis of Pseudosincirra longicirrata nov. gen. and nov. comb., isolated from southern China, were investigated with living observation and protargol staining. Our population is similar to the original population in living characteristics and ciliary patterns. The main determinable morphogenetic features of P. longicirrata nov. comb. are the presence of five frontoventral-transverse cirral anlagen (FVT-anlagen) and a dorsomarginal kinety anlage. According to the origin of FVT-anlagen IV and V in proter, it can be determined that P. longicirrata nov. comb. possesses two frontoventral rows and one right marginal row. Hence, a new genus, Pseudosincirra nov. gen., is proposed, and the diagnosis of P. longicirrata nov. comb. is improved. The new genus is diagnosed as follows: adoral zone of membranelles and undulating membranes is in a Gonostomum pattern; there are three enlarged frontal cirri, one buccal cirrus, and one parabuccal cirrus; postperistomial cirrus and transverse cirri are lacking; there are two more or less long frontoventral rows and one right and two or more left marginal rows; cirri within all rows very widely spaced; dorsal kinety pattern is of Urosomoida type, that is, three dorsal kineties and one dorsomarginal kinety; and caudal cirri are present. Phylogenetic analyses based on the small subunit ribosomal (SSU rDNA) sequence data indicate that P. longicirrata nov. comb. clusters with Deviata and Perisincirra. It is considered that Pseudosincirra nov. gen. and Perisincirra paucicirrata should be assigned to the family Deviatidae; fine cirri, and cirri within all rows being relatively widely spaced, should be considered as plesiomorphies of Deviatidae; and Deviatidae is closely related to Dorsomarginalia or Strongylidium–Hemiamphisiella–Pseudouroleptus.


Phytotaxa ◽  
2021 ◽  
Vol 480 (1) ◽  
pp. 29-44
Author(s):  
GUO-CHENG ZHANG ◽  
HUA-FENG HONG ◽  
GE-HONG CHEN ◽  
SHU-GANG LU ◽  
YAN-FEN CHANG

The Hymenasplenium obliquissimum group contains the widespread H. obliquissimum and several geographically restricted species, including H. retusulum, H. wuliangshanense, H. latidens, H. changputungense, H. quercicola, H. szechuanense, H. furfuraceum, H. adiantifrons, and H. filipes. However, the taxonomy of this group is still unclear and needs to be revised because some entities were treated infraspecifically or as synonyms and the validation of some species still needs to be assessed. To formulate a natural classification and investigate the relationships in this group, we collected and studied specimens of species related to the H. obliquissimum group and obtained specimens of species described by Ching at their locus classicus in southwestern China. An integrative taxonomic approach was taken to delimit species in the group using cytological, morphological, and DNA sequence data. Specifically, in the phylogenetic analyses, the H. obliquissimum group was recovered as a monophyletic group, comprising five principal chloroplast lineages. Based on our inferences, we provided taxonomic implications of chloroplast lineages discovered in this study and suggested possible reticulate evolution in the H. obliquissimum group which was interpreted by the incongruence of chloroplast and nuclear phylogenies. Further studies to strengthen the taxonomic of taxa especially those with the co-existence of different ploidy levels are still warranted.


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