Description of Rotylenchus arasbaranensis n. sp. from Iran with discussion on the taxonomic status of Plesiorotylenchus Vovlas, Castillo & Lamberti, 1993 (Nematoda: Hoplolaimidae)

Nematology ◽  
2014 ◽  
Vol 16 (9) ◽  
pp. 1019-1045 ◽  
Author(s):  
Mohammad Reza Atighi ◽  
Ebrahim Pourjam ◽  
Razieh Ghaemi ◽  
Majid Pedram ◽  
Gracia Liébanas ◽  
...  
Keyword(s):  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Taxonomic Status ◽  
Original Description ◽  
Molecular Data ◽  
Rrna Genes ◽  
Molecular Studies ◽  
18S Rrna Genes ◽  
First Time ◽  
Partial 18S

Rotylenchus arasbaranensis n. sp., a new monosexual species is described and illustrated based on morphological, morphometric and molecular studies. The new species is characterised by having an offset and hemispherical lip region with 5-6 annuli, 32-36 μm long stylet, vulva located at 43.9-59.2% with a single epiptygma and rounded tail, rarely bilobed, with 6-8 annuli. The species R. striaticeps and the male of R. buxophilus are reported for the first time from Iran and R. fragaricus is reported and studied for the second time after its original description. The results of the phylogenetic analyses based on the sequences of the D2-D3 expansion region of the 28S, ITS1-rRNA and the partial 18S rRNA genes were provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related taxa. Also, the validity of Plesiorotylenchus is discussed on the basis of molecular data and its synonymisation (with only one sequence) with Rotylenchus is accepted.

Studies on Longidorus iberis (Escuer & Arias, 1997) n. comb. (Nematoda: Longidoridae) from Spain

Nematology ◽  
2021 ◽  
pp. 1-15
Author(s):  
Ilenia Clavero-Camacho ◽  
Gracia Liébanas ◽  
Miguel Escuer ◽  
Carolina Cantalapiedra-Navarrete ◽  
Antonio Archidona-Yuste ◽  
...  
Keyword(s):  
Molecular Markers ◽  
18S Rrna ◽  
Molecular Data ◽  
Valid Species ◽  
28S Rrna ◽  
Closely Related Species ◽  
North West ◽  
Molecular Studies ◽  
First Time ◽  
Partial 18S

Summary Specimens of a thin longidorid species collected in Peñalba (Huesca), north-west Spain, were previously described as Paralongidorus iberis. However, we conclude, through scanning electron microscopy and molecular studies on a population from about 15 km from the type locality and on paratype specimens, that this species was originally placed in the wrong genus. Both populations have pore-like amphidial apertures, not slit-like as in Paralongidorus, and the species is therefore transferred to Longidorus. Longidorus iberis n. comb. is regarded as a valid species and is clearly different from closely related species such as L. tabernensis, L. iliturgiensis, L. alvegus and L. indalus in morphometrics and molecular markers. Molecular data are reported for the first time, including the D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, partial 18S rRNA and partial mitochondrial coxI regions. These molecular markers were used for inferring the phylogenetic relationships with other species within Longidorus and Paralongidorus, all clearly separating L. iberis n. comb. from other related taxa and placing the species in the Longidorus clade, rather than with Paralongidorus.

Phylogeny of hymenolepidids (Cestoda: Cyclophyllidea) from mammals: sequences of 18S rRNA and COI genes confirm major clades revealed by the 28S rRNA analyses

2021 ◽  
Vol 95 ◽  
Author(s):  
B. Neov ◽  
G.P. Vasileva ◽  
G. Radoslavov ◽  
P. Hristov ◽  
D.T.J. Littlewood ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
The Other ◽  
Rrna Genes ◽  
Host Switching ◽  
28S Rrna ◽  
Mitochondrial Cytochrome ◽  
Rapid Radiation ◽  
18S Rrna Genes

Abstract The aim of the study is to test a hypothesis for the phylogenetic relationships among mammalian hymenolepidid tapeworms, based on partial (D1–D3) nuclear 28S ribosomal RNA (rRNA) genes, by estimating new molecular phylogenies for the group based on partial mitochondrial cytochrome c oxidase I (COI) and nuclear 18S rRNA genes, as well as a combined analysis using all three genes. New sequences of COI and 18S rRNA genes were obtained for Coronacanthus integrus, C. magnihamatus, C. omissus, C. vassilevi, Ditestolepis diaphana, Lineolepis scutigera, Spasskylepis ovaluteri, Staphylocystis tiara, S. furcata, S. uncinata, Vaucherilepis trichophorus and Neoskrjabinolepis sp. The phylogenetic analyses confirmed the major clades identified by Haukisalmi et al. (Zoologica Scripta 39: 631–641, 2010): Ditestolepis clade, Hymenolepis clade, Rodentolepis clade and Arostrilepis clade. While the Ditestolepis clade is associated with soricids, the structure of the other three clades suggests multiple evolutionary events of host switching between shrews and rodents. Two of the present analyses (18S rRNA and COI genes) show that the basal relationships of the four mammalian clades are branching at the same polytomy with several hymenolepidids from birds (both terrestrial and aquatic). This may indicate a rapid radiation of the group, with multiple events of colonizations of mammalian hosts by avian parasites.

Morphological and molecular characterisation of Helicotylenchus ciceri n. sp. and H. scoticus Boag & Jairajpuri, 1985 (Nematoda: Hoplolaimidae) from Iran

Nematology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 611-626
Author(s):  
Fariba Mohammadi Zameleh ◽  
Akbar Karegar ◽  
Reza Ghaderi ◽  
Abbas Mokaram Hesar
Keyword(s):  
New Species ◽  
Excretory Pore ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Rrna Genes ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Closely Related Species ◽  
Partial 18S ◽  
Molecular Characters

Summary Helicotylenchus ciceri n. sp. and H. scoticus are described and illustrated based on morphological, morphometric and molecular characters. The new species is characterised by a conical and truncated lip region with five or six distinct annuli, stylet 32-37 μm long with anteriorly concave knobs, secretory-excretory pore posterior to the pharyngo-intestinal valve, dorsally convex-conoid tail with a terminal projection, phasmids 14 (7-20) annuli anterior to the level of anus, empty spermatheca and absence of males. Intraspecific variation of 16 populations of H. scoticus, collected from chickpea and lentil fields in Kermanshah province, western Iran, is discussed. The results of the phylogenetic analyses based on the sequences of the partial 18S rRNA, D2-D3 expansion segments of 28S rRNA and ITS rRNA genes are provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related species.

scholarly journals Genetic diversity in the Alpine flatworm <i>Crenobia alpina</i>

Web Ecology ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 29-35 ◽  
Author(s):  
Martin Brändle ◽  
Jan Sauer ◽  
Lars Opgenoorth ◽  
Roland Brandl
Keyword(s):  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Rrna Genes ◽  
Dispersal Ability ◽  
European Alps ◽  
Habitat Specificity ◽  
Limited Dispersal ◽  
The Alps ◽  
18S Rrna Genes ◽  
Species Speciation

Abstract. The freshwater flatworm Crenobia alpina (Platyhelminthes, Tricladida, Planariidae) lives almost exclusively in cold springs and crenal streams and possesses only limited dispersal ability. In this study fragments of the COI and 18S rRNA genes were used to estimate genetic divergences among 37 C. alpina populations from the European Alps. Phylogenetic analyses revealed five geographically and genetically distinct groups and at least 10 distinct lineages of C. alpina across the European Alps. Our study suggests that C. alpina represents a complex of numerous cryptic species. Speciation (allopatric and/or sympatric) may have been facilitated by the orogenetic activity of the Alps and the high habitat specificity.

scholarly journals An updated view of kinetoplastid phylogeny using environmental sequences and a closer outgroup: proposal for a new classification of the class Kinetoplastea

2004 ◽  
Vol 54 (5) ◽  
pp. 1861-1875 ◽  
Author(s):  
David Moreira ◽  
Purificación López-García ◽  
Keith Vickerman
Keyword(s):  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Pcr Amplification ◽  
Rrna Genes ◽  
Close Relative ◽  
New Classification ◽  
Direct Pcr ◽  
Scientific Attention ◽  
18S Rrna Genes

Given their ecological and medical importance, the classification of the kinetoplastid protists (class Kinetoplastea) has attracted much scientific attention for a long time. Morphology-based taxonomic schemes distinguished two major kinetoplastid groups: the strictly parasitic, uniflagellate trypanosomatids and the biflagellate bodonids. Molecular phylogenetic analyses based on 18S rRNA sequence comparison suggested that the trypanosomatids emerged from within the bodonids. However, these analyses revealed a huge evolutionary distance between the kinetoplastids and their closest relatives (euglenids and diplonemids) that makes very difficult the correct inference of the phylogenetic relationships between the different kinetoplastid groups. Using direct PCR amplification of 18S rRNA genes from hydrothermal vent samples, several new kinetoplastid-like sequences have been reported recently. Three of them emerge robustly at the base of the kinetoplastids, breaking the long branch leading to the euglenids and diplonemids. One of these sequences belongs to a close relative of Ichthyobodo necator (a fish parasite) and of the ‘Perkinsiella amoebae’-like endosymbiont of Neoparamoeba spp. amoebae. The authors have studied the reliability of their basal position and used all these slow-evolving basal-emerging sequences as a close outgroup to analyse the phylogeny of the apical kinetoplastids. They thus find a much more stable and resolved kinetoplastid phylogeny, which supports the monophyly of groups that very often emerged as polyphyletic in the trees rooted using the traditional, distant outgroup sequences. A new classification of the class Kinetoplastea is proposed based on the results of the phylogenetic analysis presented. This class is now subdivided into two new subclasses, Prokinetoplastina (accommodating the basal species I. necator and ‘Perkinsiella amoebae’) and Metakinetoplastina (containing the Trypanosomatida together with three additional new orders: Eubodonida, Parabodonida and Neobodonida). The classification of the species formerly included in the genus Bodo is also revised, with the amendment of this genus and the genus Parabodo and the creation of a new genus, Neobodo.

scholarly journals Molecular taxonomy of some sponges (Demospongiae) using ribosomal (18s rrna) and partial mitochondrial (coi) genes

2018 ◽  
Vol 40 (4) ◽  
Author(s):  
Ton That Huu Dat ◽  
Nguyen Thi Kim Cuc ◽  
Pham Viet Cuong
Keyword(s):  
18S Rrna ◽  
Molecular Taxonomy ◽  
Morphological Characteristics ◽  
Molecular Data ◽  
Rrna Genes ◽  
Mitochondrial Coi ◽  
Rrna Tree ◽  
The Individual ◽  
18S Rrna Genes ◽  
Relationship Of

Sponges, the most ancient multicellular metazoan, were widely distributed across habitats. Vietnam is known to possess a high biodiversity of sponges, however, they are mostly identified based on morphological characteristics and lack the molecular data. In the current study, the phylogenetic relationship of some sponges (Demospongiae) in Vietnam was constructed using two independent markers (COI and 18S rRNA). In this paper the individual markers (COI and 18S rRNA) were successfully used to identify some sponge taxa at the species level. The obtained results showed the congruence of molecular taxonomy using two independent markers. However, our study showed that a combination of the two markers provided more information and supported better for sponge identification. At order level, the COI tree and 18S rRNA tree also recovered the same clades, indicating the congruence of COI and 18S rRNA genes in sponge classification. However, branching order of the clades in COI tree was weakly supported and slightly different from those in 18S rRNA tree. 

scholarly journals Description of Longidorus cheni sp. n. (Nematoda, Longidoridae) from China

ZooKeys ◽  
2018 ◽  
Vol 744 ◽  
pp. 1-18 ◽  
Author(s):  
Eda Marie Barsalote ◽  
Hoa Thi Pham ◽  
Stela Lazarova ◽  
Vlada Peneva ◽  
Jingwu Zheng
Keyword(s):  
New Species ◽  
Morphological Characters ◽  
Molecular Data ◽  
Rrna Genes ◽  
28S Rrna ◽  
Oral Aperture ◽  
Asiatic Origin ◽  
18S Rrna Genes ◽  
Guide Ring ◽  
Partial 18S

Longidoruschenisp. n., an amphimictic species recovered from the rhizosphere ofLarixprincipis-rupprechtiiandPyracanthafortuneanain Shanxi and Beijing, China, is described and illustrated. The taxonomic position ofL.chenisp. n.among other species within the genus was elucidated using morphometric and molecular data, and phylogenetic relationships were inferred using D2–D3 expansion domains of 28S and 18S rRNA genes by Bayesian Inference (BI) method. The new species is characterised by females with a medium body size (L = 4.9–6.6 mm), a lip region slightly expanded, broadly rounded frontally and laterally, the amphidial fovea broad and symmetrically bilobed at base, odontostyle long and slender (143–168 μm), odonthophore slightly swollen at the base, tail short bluntly conoid to rounded. Guide ring located far posterior from the oral aperture (70–93 μm). Males with two ad-cloacal pairs of supplements preceded by a row of 10–14 ventromedian supplements, with robust spicules measuring 111–126 μm along the median line. Three juvenile stages were present, tail shape of J1 elongate conoid while in J2 and J3 the tail gradually becomes bluntly rounded. Codes for identifying the new species are: A6-B3-C5-D2-E2-F3-G1-H1-I2-J2-K2.Longidoruschenisp. n.belongs to a group of species with a guide ring at the mid-odontostyle position that have a predominantly Asiatic origin. It differs from all of them by a combination of morphological characters and unique sequences of partial 18S and D2–D3 region of 28S rRNA genes. The percentage dissimilarities in partial 18S and D2–D3 28S rRNA genes ofL.chenito the closest species (L.litchii,L.fangi,L.jonesiandL.juglans) were 1.5 %–1.8 % and 16.8–18.3 %, respectively.

A morphological and molecular reinvestigation of Janickina pigmentifera (Grassi, 1881) Chatton 1953 – an amoebozoan parasite of arrow-worms (Chaetognatha)

2021 ◽  
Vol 71 (11) ◽  
Author(s):  
Ekaterina Volkova ◽  
Alexander Kudryavtsev
Keyword(s):  
18S Rrna ◽  
Phylogenetic Analyses ◽  
18S Rrna Gene ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Intracellular Symbiont ◽  
Microscopic Features ◽  
Parasitic Lifestyle ◽  
18S Rrna Genes ◽  
Arrow Worms

Amoebozoan parasites of arrow-worms (Chaetognatha) were isolated from their hosts living in plankton of the Bay of Villefranche (Mediterranean Sea). Based on the light microscopic characters, the amoebae were identified as Janickina pigmentifera (Grassi, 1881) by their limax locomotive form and due to the presence of the intracellular symbiont, Perkinsela amoebae, surrounded by a layer of pigment granules. Sequences of the 18S rRNA gene of both J. pigmentifera and its symbiont were obtained for the first time. The molecular phylogenetic analyses of 18S rRNA gene placed J. pigmentifera within the genus Neoparamoeba, a taxon also characterized by the presence of a symbiont, known as Perkinsela amoebae-like organism (PLO). The 18S rRNA gene sequence of P. amoebae from J. pigmentifera grouped with the sequences of 18S rRNA genes of PLOs from Neoparamoeba branchiphila and Neoparamoeba invadens. The first photo documentation of the light microscopic features of J. pigmentifera, such as locomotive form, the morphology of the nucleus and P. amoebae have been provided. The new results support the affinity of J. pigmentifera with the family Paramoebidae suggested previously based on the presence of PLO. In contrast to Janickina, typical members of Paramoebidae (Neoparamoeba and Paramoeba) have a flattened, dactylopodial locomotive form. This discrepancy in morphology can be explained by the obligate parasitic lifestyle of Janickina.

The use of large and small subunits of ribosomal DNA in evaluating phylogenetic relationships between species ofCornudiscoidesKulkarni, 1969 (Monogenoidea: Dactylogyridae) from India

2016 ◽  
Vol 91 (2) ◽  
pp. 206-214 ◽  
Author(s):  
J. Verma ◽  
N. Agrawal ◽  
A.K. Verma
Keyword(s):  
Ribosomal Dna ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Rrna Genes ◽  
28S Rrna ◽  
Ganges River ◽  
Mystus Vittatus ◽  
Ribosomal Subunits ◽  
18S Rrna Genes ◽  
High Degree

AbstractTwo partial regions of ribosomal DNA (28S and 18S) were used to evaluate genetic variations among the species ofCornudiscoides,viz.C. proximus, C. geminusandC. agarwali, all parasites ofMystus vittatus(Bagridae) from River Gomati, Ganges River basin, India. Our findings demonstrated that both the large and small ribosomal subunits are useful for species identification and genetic characterization of parasites, leading to resolution of inter/intra-relationships at generic and specific levels. The secondary structures of all three species for 28S and 18S rRNA genes contained exact pattern matches (EMPs) displaying the high degree of similarity among them. The phylogenetic analyses within the members of Dactylogyridae demonstrated that species ofCornudiscoidescluster together for 28S rRNA and 18S rRNA genes.

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