Morphology, molecular characterisation and systematic position of Hemiplectus muscorum Zell, 1991 (Nematoda: Plectida)

Nematology ◽  
2009 ◽  
Vol 11 (5) ◽  
pp. 719-737 ◽  
Author(s):  
Oleksandr Holovachov ◽  
Sven Boström ◽  
Manuel Mundo-Ocampo ◽  
Irma Tandingan De Ley ◽  
Melissa Yoder ◽  
...  
Keyword(s):  
Molecular Data ◽  
Small Subunit ◽  
Systematic Position ◽  
Molecular Characterisation ◽  
Posterior Pair ◽  
The Usa ◽  
New Material ◽  
Juvenile Stages ◽  
The Uk ◽  
Rrna Sequences

Abstract Hemiplectus muscorum, the type and single representative of its genus, is redescribed on the basis of abundant new material collected in the UK, Canada and the USA using both light and scanning electron microscopy. The phylogenetic relationships of the species are inferred from morphological as well as molecular data. Maximum parsimony, neighbour joining and maximum likelihood analyses of small subunit (SSU) rRNA sequences support a position nested among the Plectidae. This conflicts with our morphological assumptions of character polarity, as it implies that the absence of a valvate bulb in Hemiplectus is a reversal rather than a plesiomorphy. The excretory system of Hemiplectus is described more precisely. Its structure is highly reminiscent of the system in Plectus but differs in the presence of an anterior and posterior pair of pseudocoelomocytes flanking the renette cell. A pair of lateral somatic setae is identified as possible homologues of the 'deirids' in Plectus and Rhabditida. Measurements and descriptions are given of all four juvenile stages.

Morphology, molecular characterisation and systematic position of the genus Cynura Cobb, 1920 (Nematoda: Plectida)

Nematology ◽  
2013 ◽  
Vol 15 (5) ◽  
pp. 611-627 ◽  
Author(s):  
Oleksandr Holovachov ◽  
Sven Boström ◽  
Irma Tandingan De Ley ◽  
Cymphonee Robinson ◽  
Manuel Mundo-Ocampo ◽  
...  
Keyword(s):  
Marine Environment ◽  
Phylogenetic Relationships ◽  
Molecular Data ◽  
Small Subunit ◽  
Systematic Position ◽  
Molecular Characterisation ◽  
Bayesian Analyses ◽  
Sem Micrographs ◽  
Rrna Sequences

Descriptions of three known species of Cynura, i.e., C. cerambus, C. klunderi and C. papillata, are given, including SEM micrographs of C. cerambus and a tabular compendium for all species of the genus. The phylogenetic relationships of C. klunderi are inferred from molecular data. Bayesian analyses of small subunit (SSU) of rRNA sequences support a position nested among the Plectidae suggesting the secondary simplification in the morphology of pharyngeal valvular apparatus in Cynura and the ‘return’ from a terrestrial to a marine environment in this genus.

Morphological and molecular characterisation of Xiphinema mazandaranense n. sp. (Dorylaimida: Longidoridae), a new member of the Xiphinema pyrenaicum species complex

Nematology ◽  
2012 ◽  
Vol 14 (1) ◽  
pp. 109-119 ◽  
Author(s):  
Majid Pedram ◽  
Ebrahim Pourjam ◽  
Robert T. Robbins ◽  
Weimin Ye ◽  
Mohammad Reza Atighi ◽  
...  
Keyword(s):  
New Species ◽  
Species Complex ◽  
Small Subunit ◽  
Molecular Characterisation ◽  
Molecular Analyses ◽  
Small Subunit Rdna ◽  
Group 6 ◽  
Close Relationship ◽  
Juvenile Stages ◽  
Female Genital

Xiphinema mazandaranense n. sp. is described and illustrated. The new species belongs to morphospecies group 6, which is characterised by having two equally developed female genital branches that have spines in the uteri and a short, rounded tail. The new species is characterised by having spines in the tubular portion of the uterus, body 3.7-5.2 mm long, odontostyle 163-173 μm long, odontophore 96-100 μm long, body 62-80 μm diam., rounded tail, four juvenile stages, males rare with three ventromedian supplements next to the adcloacal pair and spicules 85 μm long. The polytomous identification codes of the new species are: A4-B3-C7b-D6-E456-F45-G4-H2-I23-J7b-K2-L1. The new species appears closely related to the members of X. pyrenaicum group which are characterised by a rounded tail with or without an inconspicuous projecting bulge and a uterus devoid of Z-differentiation but showing spiniform structures. The new species differs from members of the X. pyrenaicum group, which includes the recently described X. iranicum, by a more rounded tail without any projection. Beside morphological and morphometric data, molecular analyses of the near-full-length small subunit rDNA gene (SSU) placed the new species in close relationship with some species belonging to Xiphinema morphospecies group 6 and further separated this species from the X. pyrenaicum complex.

Heterocyphelium leucampyx (Arthoniales, Ascomycota): another orphaned mazaediate lichen finds its way home

2017 ◽  
Vol 49 (4) ◽  
pp. 333-345 ◽  
Author(s):  
Dries VAN DEN BROECK ◽  
Robert LÜCKING ◽  
Ester GAYA ◽  
José Luis CHAVES ◽  
Julius B. LEJJU ◽  
...  
Keyword(s):  
Rna Polymerase Ii ◽  
Ribosomal Rna ◽  
Sequence Data ◽  
Parallel Evolution ◽  
Single Species ◽  
Molecular Data ◽  
Small Subunit ◽  
Systematic Position ◽  
The Past ◽  
The Family

AbstractHeterocyphelium is a mazaediate genus containing a single species, H. leucampyx. The species was originally described from Cuba within the genus Trachylia (Arthoniales, Arthoniaceae) and later placed in various genera of the collective order Caliciales s. lat. For the past three decades, Heterocyphelium was considered an orphaned genus (incertae sedis) within the Ascomycota, since morphology alone could not resolve its systematic position. In this study, we added molecular data with the aim of resolving this uncertainty. Bayesian and maximum likelihood analyses of newly generated sequence data from the mitochondrial ribosomal RNA small subunit (mtSSU) and the RNA polymerase II second largest subunit gene (RPB2) provide clear evidence that Heterocyphelium leucampyx is nested within the order Arthoniales, in the family Lecanographaceae, sister to the genus Alyxoria. Heterocyphelium is a further example of parallel evolution of passive spore dispersal, prototunicate asci and the occurrence of a mazaedium in the Ascomycota, and another calicioid genus whose systematic placement could be eventually clarified by means of molecular data. Heterocyphelium is the fourth mazaediate genus in Arthoniales, in addition to Sporostigma, Tylophorella and Tylophoron.

Redescription of Placodira lobata Thorne, 1937 (Rhabditida: Cephalobidae) with a discussion of the systematic position of the genus

Nematology ◽  
2011 ◽  
Vol 13 (1) ◽  
pp. 103-114 ◽  
Author(s):  
Irma Tandingan De Ley ◽  
Steven Nadler ◽  
Sven Boström ◽  
Cymphonee Robinson ◽  
Oleksandr Holovachov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Relationships ◽  
Molecular Data ◽  
Systematic Position ◽  
Type Specimens ◽  
The Usa ◽  
Scanning Electron

AbstractA population of Placodira lobata from the USA is described using both light and scanning electron microscopy and compared with the descriptions of the type specimens of the same species. The phylogenetic relationships of the species are inferred from molecular data and places P. lobata in a clade that unites genera with mostly simple morphology of the labial region, like Cephalobus, Acrobeloides, Heterocephalobellus and Metacrobeles, but also includes species of Zeldia and Chiloplacus.

An early mainstream economist from Hungary: István Varga (1897–1962)

2003 ◽  
Vol 53 (2) ◽  
pp. 195-213 ◽  
Author(s):  
K. Majoros
Keyword(s):  
Austrian Economic ◽  
National Income ◽  
Anglo Saxon ◽  
Turbulent Times ◽  
The Usa ◽  
New Ideas ◽  
Modern Economic ◽  
The Uk ◽  
Economic Thinking ◽  
Lasting Influence

The study introduces a Hungarian economic thinker, István Varga*, whose valuable activity has remained unexplored up to now. He became an economic thinker during the 1920s, in a country that had not long before become independent of Austria. The role played by Austria in the modern economic thinking of that time was a form of competition with the thought adhered to by the UK and the USA. Hungarian economists mainly interpreted and commented on German and Austrian theories, reasons for this being that, for example, the majority of Hungarian economists had studied at German and Austrian universities, while at Hungarian universities principally German and Austrian economic theories were taught. István Varga was familiar not only with contemporary German economics but with the new ideas of Anglo-Saxon economics as well — and he introduced these ideas into Hungarian economic thinking. He lived and worked in turbulent times, and historians have only been able to appreciate his activity in a limited manner. The work of this excellent economist has all but been forgotten, although he was of international stature. After a brief summary of Varga’s profile the study will demonstrate the lasting influence he has had in four areas — namely, business cycle research and national income estimations, the 1946 Hungarian stabilisation program, corporate profit, and consumption economics — and will go on to summarise his most important achievements.

Neurosurgical activity during COVID-19 pandemic: an experts' opinion from China, South Korea, Italy, the USA, Colombia, and the UK

2020 ◽  
Vol 64 (4) ◽  
Author(s):  
Marco M. Fontanella ◽  
Giorgio Saraceno ◽  
Ting Lei ◽  
Joshua B. Bederson ◽  
Namkyu You ◽  
...  
Keyword(s):  
South Korea ◽  
The Usa ◽  
The Uk

Benchmarking Risk Analysis Practice in the International Water Sector

2006 ◽  
Vol 1 (2) ◽  
Author(s):  
B.H. MacGillivray ◽  
P.D. Hamilton ◽  
S.E. Hrudey ◽  
L. Reekie ◽  
S.J.T Pollard
Keyword(s):  
Decision Making ◽  
Risk Analysis ◽  
Water Utilities ◽  
Water Sector ◽  
Water Utility ◽  
Analysis Techniques ◽  
The Usa ◽  
International Water ◽  
Practical Guidance ◽  
The Uk

Risk analysis in the water utility sector is fast becoming explicit. Here, we describe application of a capability model to benchmark the risk analysis maturity of a sub-sample of eight water utilities from the USA, the UK and Australia. Our analysis codifies risk analysis practice and offers practical guidance as to how utilities may more effectively employ their portfolio of risk analysis techniques for optimal, credible, and defensible decision making.

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