Molecular and morphological characterisation of Trichodorus species (Nematoda: Trichodoridae), with description of T. pseudoaequalis n. sp. from California and other states of the USA

Nematology ◽  
2020 ◽  
pp. 1-28
Author(s):  
Wilfrida Decraemer ◽  
Sergei A. Subbotin
Keyword(s):  
Integrated Approach ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Posterior Half ◽  
Head Region ◽  
Male Characters ◽  
The Usa ◽  
Pharyngeal Gland ◽  
One New Species

Summary During surveys for stubby root nematodes in the natural vegetation of California, Oregon and Washington, USA, three known species, viz., Trichodorus californicus, T. intermedius and T. obscurus were recovered together with ten unidentified Trichodorus species. The three known and one new species were studied using an integrated approach. Trichodorus pseudoaequalis n. sp. is characterised by a medium-sized body about 800 μm long on average, male with two ventromedian cervical papillae anterior to secretory-excretory pore and three precloacal supplements all located anterior to the retracted spicules; spicules 39 μm long (average), slightly ventrally curved, more so in head region and blade with slight indentation mid-way and striation more pronounced in posterior half. Females possess a rather short (average 33% of corresponding body diam.) pear-shaped vagina with small vaginal sclerotised pieces (ca 1.5 μm long), rounded triangular in shape, obliquely orientated and close together; one pair of sublateral body pores anterior (about four vulval body diam.) to vulva and one pair of post-advulvar sublateral body pores. Trichodorus pseudoaequalis n. sp. differs from the most similar species, T. aequalis, in male characters like general spicule shape and ornamentation and in the position of the dorsal pharyngeal gland nucleus in both sexes (at same level of posterior ventrosublateral pair vs clearly separated). The phylogenetic relationships of the recovered species were reconstructed using the ITS2 rRNA and the D2-D3 expansion segments of 28S rRNA gene sequences.

Synonymy of Afenestrata with Heterodera supported by phylogenetics with molecular and morphological characterisation of H. koreana comb. n. and H. orientalis comb. n. (Tylenchida: Heteroderidae)

Nematology ◽  
2008 ◽  
Vol 10 (5) ◽  
pp. 611-632 ◽  
Author(s):  
Manuel Mundo-Ocampo ◽  
Alberto Troccoli ◽  
Sergei A. Subbotin ◽  
Julio Del Cid ◽  
James G. Baldwin ◽  
...  
Keyword(s):  
Morphological Identification ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Diagnostic Pcr ◽  
Second Stage ◽  
Pcr Rflp ◽  
Identification Of Species ◽  
Its Rrna ◽  
Labial Disc

Abstract Phylogenetic analysis of five gene fragments: ITS-rRNA, D2 and D3 of 28S rRNA, 18S rRNA, Hsp90 and actin, of Heterodera species and two representative Afenestrata species, A. koreana and A. orientalis, form a clade with H. cynodontis, H. bifenestra and an unidentified Heterodera sp. infecting grasses. Based on these results and the consideration that the key diagnostic characters of Afenestrata are convergent and do not define a clade, synonymisation of Afenestrata with Heterodera is proposed. The following new combinations are made: H. africana comb. n., H. axonopi comb. n., H. koreana comb. n., and H. orientalis comb. n. Furthermore, H. (= Afenestrata) sacchari is renamed as H. saccharophila nom. nov. to avoid homonymy. All these species, together with H. bamboosi, are regarded as members of a paraphyletic ‘Afenestrata group’ within Heterodera. Whilst recognised as artificial, the Afenestrata group is nevertheless an aid to discussion about these similar species. Morphological and molecular characterisation of populations of H. koreana comb. n. from Florida and H. orientalis comb. n. from Florida and Guatemala verify the identification of these populations as valid representatives for molecular studies of the species. Light and SEM observations also provide new detail and a broader understanding of the morphological range of both species. These include a longer stylet for females of H. koreana comb. n. and H. orientalis comb. n. than reported in the original descriptions. In addition, previously unreported tuberculate ridges are noted on the surface of vulval lips of H. orientalis comb. n. The lip region of second-stage juveniles of H. koreana comb. n. and H. orientalis comb. n. both include fused adjacent submedian lips that also fuse with the labial disc and the second lip annulus. The ITS-rRNA gene sequences of H. orientalis comb. n. populations from Florida and Guatemala were similar to those from the Russian type locality. Diagnostic PCR-RFLP of ITS-rRNA profiles with six enzymes for H. orientalis comb. n. and H. koreana comb. n. are given. A key for the morphological identification of species of the Afenestrata group is provided.

Additional data on Pratylenchoides riparius (Andrássy, 1985) Luc, 1986 (Nematoda: Merliniidae) from Iran

Nematology ◽  
2019 ◽  
Vol 21 (8) ◽  
pp. 827-836 ◽  
Author(s):  
Manouchehr Hosseinvand ◽  
Ali Eskandari ◽  
Reza Ghaderi
Keyword(s):  
Taxonomic Status ◽  
Molecular Data ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Lateral Field ◽  
Molecular Phylogenetic ◽  
Type Population ◽  
Stylet Length

Summary The second population of Pratylenchoides riparius, including females and males, is described and illustrated based upon morphological, morphometric and molecular data. The present population from Iran is characterised by some differences with the type population of the species from Hungary in stylet length (24-26 vs 21-22 μm), slightly longer body (1002-1230 vs 830-960 μm), pharynx (202-211 vs 182-190 μm) and tail (64-85 vs 48-57 μm), areolated outer bands of the lateral field (vs non-areolated), widening of the lateral field near tail terminus (vs lateral incisures connecting each other) and presence of males (vs absent). The taxonomic status of the species with regarding the data from the type and presently recovered population, as well as the closely similar species is discussed. The newly recovered population was studied based upon its molecular phylogenetic charactes using the D2-D3 of 28S rRNA and the partial 18S rRNA gene sequences and the results revealed that it forms a clade with P. magnicauda in 28S, but occupies a distant placement from it in 18S phylogeny.

Description of Longidorus barsii Radivojević & De Luca sp. n. (Nematoda: Longidoridae) from Serbia and observations on some taxonomic characters

Nematology ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 555-576
Author(s):  
Milan Radivojević ◽  
László Barsi ◽  
Elena Fanelli ◽  
Francesca De Luca
Keyword(s):  
Its Region ◽  
Balkan Peninsula ◽  
Body Region ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Oral Aperture ◽  
Dorsal Nucleus ◽  
28S Rrna Gene ◽  
Anterior Body

Summary Longidorus barsii sp. n., from Mt Tara in the Balkan Peninsula, is described and characterised by using a polyphasic approach. The species has numerous males. The female body is 5-7 mm long, rather stout and resembles a large Xiphinema. The lip region is wide, with rounded sides continuous with the neck, frontally flattened and depressed around the oral aperture, amphids are pouch-like and distinctly bi-lobed and the odontostyle is moderately long. The nuclei of the pharyngeal glands are in the normal position, the dorsal nucleus located somewhat posterior to anterior third of bulb. The uteri are long, the distal inner epithelium densely covered with papilla-like outgrowths. The tail is rounded, bluntly conoid and very short. Alpha-numerical identification codes: A4/5, B45, C3, D3, E2, F3, G 1(2), H1, I2, J1, K67. The morphologically most similar species are L. kheirii, L. polyae and L. profundorum. Additional observations are provided on the anterior body region and genital organs in L. barsii sp. n., L. piceicola, L. silvae, and L. uroshis. Selected features are discussed from the taxonomic and functional points of view. The D2-D3 expansion domains of the 28S rRNA gene and the ITS region of L. barsii sp. n. were amplified and sequenced. Phylogenetic analysis using the D2-D3 expansion domains of the 28S rRNA gene revealed close evolutionary relationships with L. polyae, L. athesinus and three unidentified Longidorus spp.

Molecular phylogeny and systematics of cestodes with rudimentary rostellum (Cestoda: Hymenolepididae) from Holarctic Sorex shews (Eulipotyphla: Soricidae)

2019 ◽  
Vol 187 (3) ◽  
pp. 965-986
Author(s):  
Svetlana A Kornienko ◽  
Rasa Binkienė ◽  
Nikolai E Dokuchaev ◽  
Vasyl V Tkach
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Phylogeny ◽  
Type Species ◽  
Taxonomic Status ◽  
Genetic Data ◽  
Molecular Study ◽  
Morphological Characters ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna

Abstract We analyse the phylogenetic relationships and taxonomic status of hymenolepidid cestodes with rudimentary rostellum, parasitic in Holarctic shrews of the genus Sorex. These cestodes were previously termed as a ‘Ditestolepis clade’ and encompass eight genera: Diorchilepis, Ditestolepis, Ecrinolepis, Gulyaevilepis, Mathevolepis, Novobrachylepis, Spalania and Spasskylepis. Representatives of seven of these were available for molecular study, including type species of all seven genera. Phylogenetic analysis based on partial sequences of the 28S rRNA gene supports this group of genera as monophyletic. The ‘Ditestolepis clade’ consists of two subclades. One of these includes genera containing cestodes having suckers positioned inside bothrium-like depressions (Ditestolepis, Gulyaevilepis and Spasskylepis). The second subclade contains cestodes with suckers expanding far beyond the margins of the scolex (Mathevolepis, Ecrinolepis, Spalania and Novobrachylepis). The relative taxonomic value of several additional morphological characters is discussed. Genetic data convincingly demonstrate that Ditestolepis diaphana, Spasskylepis ovaluteri and Mathevolepis macyi represent complexes of morphologically similar species. Based on the phylogenetic analysis, we resurrect the genus Spalania. Amended generic diagnoses and keys to identification of the genera in the Ditestolepis clade, as well as keys to the known species, are provided.

Molecular characterisation of some stubby root nematodes (Nematoda: Trichodoridae) from the USA and other countries

Nematology ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Sergei A. Subbotin ◽  
Ignacio Cid Del Prado Vera ◽  
Renato N. Inserra ◽  
Vladimir N. Chizhov ◽  
Wilfrida Decraemer
Keyword(s):  
Nematode Species ◽  
Rrna Gene ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
28S Rrna Gene ◽  
Putative Species ◽  
Geographical Regions ◽  
Wide Range ◽  
The Usa ◽  
Stubby Root Nematode

Summary The stubby root nematodes are world-wide distributed polyphagous root ectoparasites and can cause damage to a wide range of crops and natural vegetation. In this study, 22 valid and putative species of stubby root nematodes were identified in 37 samples collected in Malaysia, Mexico, Russia, and the USA (California, Florida, Minnesota and Nevada). The analysis of 58 new sequences of the D2-D3 expansion fragments of 28S rRNA gene revealed the following species: Nanidorus minor from California, Florida and Mexico, N. renifer from Florida, two unidentified Nanidorus species from California and Malaysia, respectively, Paratrichodorus allius from Florida and Minnesota, P. pachydermus and Paratrichodorus sp. from Russia, Trichodorus californicus, T. intermedius, and T. obscurus from California, T. obtusus from Florida, eight unidentified Trichodorus species from California, one unidentified Trichodorus species from Nevada, and two unidentified species of stubby root nematodes, one of Trichodorus and another undetermined species from Mexico. Molecular characterisation of T. californicus, T. intermedius and T. obscurus is given for the first time. The phylogenetic tree reconstructed from the analysis of 108 D2-D3 of 28S rRNA gene sequences of 58 valid and putative species of the stubby root nematodes contained five major clades: i) Trichodorus from Europe, Asia and North America; ii) Nanidorus and Trichodorus from Asia; iii) Trichodorus from California; iv) Paratrichodorus from several distant geographical regions; and v) Monotrichodorus from Central and South America. It has been hypothesised that the California Floristic Province is one of the centres of origin and diversification of stubby root nematodes. There is no information on the economic importance of the stubby root nematode species found in California and Mexico. The confirmation of the occurrence of N. renifer and P. allius in Florida should be of concern for the blueberry and potato industries in the state.

scholarly journals Morphological and molecular characterisation of Paralongidorus plesioepimikis n. sp. (Nematoda: Longidoridae) from southern Spain

Nematology ◽  
2013 ◽  
Vol 15 (3) ◽  
pp. 363-378 ◽  
Author(s):  
Juan E. Palomares-Rius ◽  
Carolina Cantalapiedra-Navarrete ◽  
Carlos Gutiérrez-Gutiérrez ◽  
Gracia Liébanas ◽  
Pablo Castillo
Keyword(s):  
Anterior Part ◽  
Phylogenetic Analyses ◽  
Southern Spain ◽  
Rrna Gene ◽  
28S Rrna ◽  
Data Set ◽  
Cephalic Lobe ◽  
Pharyngeal Gland ◽  
Amphidial Fovea ◽  
Partial 18S

Paralongidorus plesioepimikis n. sp. is described and illustrated by light microscopy, scanning electron microscopy and molecular studies from specimens collected in a sandy soil in the rhizosphere of stone pine (Pinus pinea) in Bonares (Huelva Province), southern Spain. The new species is characterised by a very long body (9.71-14.11 mm), an expanded and rounded lip region, with a clear constriction followed by a depression posterior to the amphidial aperture, a very long and flexible odontostyle (202-227 μm), guiding ring located at 36.5-44.0 μm from anterior end, dorsal pharyngeal gland nucleus in anterior part of bulb, one subventral pair of nuclei near middle of bulb, vulva at 33-38%, and a dorsally convex tail with rounded terminus (32-39 μm long). SEM observations showed a very large amphidial fovea with conspicuous aperture ca three-fourths as wide as lip region and cephalic papillae appearing as small apertures, each located just anterior to a distinct cephalic lobe. The sequences of the D2-D3 expansion segments of 28S rRNA, partial 18S rRNA and ITS rRNA gene for P. plesioepimikis n. sp. were obtained. Phylogenetic analyses of P. plesioepimikis n. sp. rRNA gene sequences and of Paralongidorus spp. and Longidorus spp. sequences published in GenBank were done using Maximum Likelihood and Bayesian inference. Paralongidorus species (including P. plesioepimikis n. sp.) clustered together, except for P. bikanerensis which clustered within Longidorus spp. and was clearly separated from all other Paralongidorus spp. in trees generated from the D2-D3 expansion segments of 28S and partial 18S data set. ML analysis using SH-test for the validity of Paralongidorus was performed and showed the validity of the genus using the D2-D3 expansion segment of 28S and partial 18S.

Morphological and molecular characterisation of some Hemicriconemoides species (Nematoda: Criconematidae) together with a phylogeny of the genus

Nematology ◽  
2014 ◽  
Vol 16 (5) ◽  
pp. 519-553 ◽  
Author(s):  
Esther Van den Berg ◽  
Louwrens R. Tiedt ◽  
Renato N. Inserra ◽  
Jason D. Stanley ◽  
Nicola Vovlas ◽  
...  
Keyword(s):  
Fruit Trees ◽  
Valid Species ◽  
Rrna Gene ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Electron Microscopic ◽  
Specific Primers ◽  
Scanning Electron Microscopic ◽  
The Usa ◽  
Species Specific

Sheathoid nematodes of the genusHemicriconemoidesare migratory root-ectoparasites of many plants including various agricultural crops and fruit trees. They are generally found inhabiting warm areas of the world and presently consist of 52 valid species. In this study we provide morphological and molecular characterisation of 12 species of this genusviz.:H. alexis,H. brachyurus,H. californianus,H. chitwoodi,H. macrodorus,H. minutus,H. ortonwilliamsi,H. promissus,H. silvaticus,H. strictathecatus,H. wessoniandHemicriconemoidessp. originating from China, Greece, Japan, Myanmar, Spain, South Africa and the USA. Morphological descriptions, measurements, light and scanning electron microscopic observations and drawings are given for several species. Phylogenetic relationships withinHemicriconemoides, as inferred from the analyses of the D2-D3 of 28S rRNA and ITS-rRNA gene sequences, resulted in trees with three major clades that corresponded with species groupings based on morphology of the lip pattern and vulval flap. PCR with species-specific primers were developed forH. californianus,H. chitwoodiandH. strictathecatus.

Description of Bursaphelenchus ulmophilus sp. n. (Nematoda: Parasitaphelenchinae) associated with Dutch elm disease of Ulmus glabra Huds. in the Russian North West

Nematology ◽  
2015 ◽  
Vol 17 (6) ◽  
pp. 685-703 ◽  
Author(s):  
Alexander Ryss ◽  
Kristina S. Polyanina ◽  
Boris G. Popovichev ◽  
Sergei A. Subbotin
Keyword(s):  
Bark Beetles ◽  
Phylogenetic Analyses ◽  
Nematode Species ◽  
Dutch Elm Disease ◽  
Rrna Gene ◽  
28S Rrna ◽  
North West ◽  
Ulmus Glabra ◽  
Russian North ◽  
Pharyngeal Gland

A new species,Bursaphelenchus ulmophilussp. n., from thehofmannigroup is described morphologically and molecularly. This nematode species was found associated with Dutch elm disease ofUlmusglabrain parks of St Petersburg, Russia, and is vectored by adults and larvae of the bark beetlesScolytusmultistriatusandS. scolytus.Bursaphelenchus ulmophilussp. n. is characterised by the following features: body length 600-850 μm, stylet 12-14 μm long with base slightly and smoothly expanded, but lacking knobs, median bulb almost spherical in female and slightly ovoid in male, pharyngeal gland lobe dorsal, 4-5 body diam. long. This species has an oval spermatheca filled with spherical nucleic sperm 4-5 μm diam. Female post-uterine sacca0.5 of the vulva-anus distance andca3 vulval body diam. long, female tail reflexed, strongly hooked ventrally with a digitate or conically rounded tip. The male has seven caudal papillae arranged as 1 + 2 + 2 + 2, P1 is unpaired, anterior to cloacal opening, paired P2 at cloacal aperture, paired P3 and paired pore-like ‘gland papilla’ P4 at the lateral edges of the bursa which has the posterior border rounded to truncate. Phylogenetic analyses of the D2-D3 of 28S rRNA, partial 18S rRNA and ITS rRNA gene sequences revealed thatB. ulmophilussp. n. formed a clade with species of thehofmannigroup and shared close relationships withB. hofmanniandB. pinasteri.

Phylogenetic Analysis Using the 28S rRNA Gene Reveals That the GenusParacreptotrema(Digenea: Allocreadiidae) Is Not Monophyletic; Description of Two New Genera and One New Species

2016 ◽  
Vol 102 (1) ◽  
pp. 131-142 ◽  
Author(s):  
Gerardo Pérez-Ponce de León ◽  
Carlos D. Pinacho-Pinacho ◽  
Berenit Mendoza-Garfias ◽  
Anindo Choudhury ◽  
Martín García-Varela
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Rrna Gene ◽  
28S Rrna ◽  
New Genera ◽  
28S Rrna Gene ◽  
One New Species

Bursaphelenchus juglandis n. sp. (Nematoda: Aphelenchoididae), an associate of walnut twig beetle, Pityophthorus juglandis, the vector of thousand cankers disease

Nematology ◽  
2020 ◽  
pp. 1-30
Author(s):  
Alexander Y. Ryss ◽  
Corwin Parker ◽  
Sergio Álvarez-Ortega ◽  
Steven A. Nadler ◽  
Sergei A. Subbotin
Keyword(s):  
Developmental Stages ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Similar Species ◽  
28S Rrna ◽  
Lateral Field ◽  
Pityophthorus Juglandis ◽  
Thousand Cankers Disease ◽  
Species Specific ◽  
Walnut Twig Beetle

Summary Bursaphelenchus juglandis n. sp. was isolated from the walnut twig beetle, Pityophthorus juglandis, and walnut trees, Juglans spp. with symptoms of thousand cankers disease, in California, USA. Based on analysis of three rRNA genes and morphological features (three lines in lateral field, small arched vulval flap in female, broad spicule with two lines along blade and small cucullus, digitate dorsally bent condylus, male tail pattern of five papilliform papillae and one pair of glandpapillae (P5), and curved conical female tail), the new species belongs to the Abietinus group within Bursaphelenchus. It differs from similar species of this group by the presence of a cephalic disc with lateral labial sensilla at the disc border, and in having thick spicules with the capitulum surface almost parallel to a virtual direct line extending from the spicule end. An emended diagnosis, tabular polytomous identification key and compendium of species with the lists of their vectors, plant hosts, and distribution are provided for the Abietinus group. The diagnostics of the propagative developmental stages is given, including sex differences; the transmission dauer stage was identified as the third stage and its description given with sexual differences. A molecular phylogeny of Bursaphelenchus is provided based on partial 18S rRNA, ITS rRNA and the D2-D3 expansion fragments of 28S rRNA gene sequences. A PCR with a species-specific primer was developed for detection of B. juglandis n. sp.

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