Ditylenchus gallaeformans sp. n. (Tylenchida: Anguinidae) – a neotropical nematode with biocontrol potential against weedy Melastomataceae

Nematology ◽  
2013 ◽  
Vol 15 (2) ◽  
pp. 179-196 ◽  
Author(s):  
Rosângela D.L. Oliveira ◽  
Ângelo M. Santin ◽  
Dalila J. Seni ◽  
Anna Dietrich ◽  
Luis A. Salazar ◽  
...  
Keyword(s):  
New Species ◽  
Severe Disease ◽  
Molecular Study ◽  
Rrna Gene ◽  
28S Rrna ◽  
Leaf Spots ◽  
Miconia Calvescens ◽  
Biocontrol Potential ◽  
Tail Tip ◽  
Species Specific

Ditylenchus gallaeformans sp. n. was found on several hosts at numerous locations in Brazil and Costa Rica. In its native habitats it attacks several genera in the Melastomataceae, including two species ranked as among the worst invasive weeds of Pacific island forests, namely Miconia calvescens and Clidemia hirta. The new species causes a severe disease on infected plants involving the formation of gall-like structures on infected leaves, inflorescences and stems, and may cause significant impact on its hosts. Morphological study using light and scanning electron microscopy and analysis of the partial 18S rRNA, the D2-D3 expansion fragments of 28S rRNA and the ITS rRNA gene sequences showed little variations between populations from different hosts or geographical origins. The molecular study revealed that the new species is related to D. drepanocercus, which was recently found in association with M. calvescens but causing angular leaf spots on this host. Ditylenchus gallaeformans sp. n. is distinguished from D. drepanocercus by having a bursa reaching the tail tip (vs covering around 50% of tail in D. drepanocercus) and a conical tail, regularly tapering towards a variable tip (vs tail with a distinctive apical falciform appendage in both sexes in D. drepanocercus). PCR with species-specific primers was developed for diagnostics of both Ditylenchus species. Ditylenchus gallaeformans sp. n. deserves further investigation as a potential biocontrol agent against M. calvescens and C. hirta.

Description of Tylenchulus musicola sp. n. (Nematoda: Tylenchulidae) from banana in Iran with molecular phylogeny and characterisation of species of Tylenchulus Cobb, 1913

Nematology ◽  
2012 ◽  
Vol 14 (3) ◽  
pp. 353-369 ◽  
Author(s):  
Zahra Tanha Maafi ◽  
Majid Amani ◽  
Jason D. Stanley ◽  
Renato N. Inserra ◽  
Esther Van den Berg ◽  
...  
Keyword(s):  
New Species ◽  
Rapid Identification ◽  
Rrna Genes ◽  
Rrna Gene ◽  
28S Rrna ◽  
Specific Primers ◽  
Diagnostic Pcr ◽  
Second Stage ◽  
Species Specific ◽  
A New Species

During a survey conducted on banana plantations in Sistan and Blouchestan province, south-east Iran, a new species of Tylenchulus was extracted from the soil and roots of banana plants. This species, named Tylenchulus musicola sp. n., is characterised by mature females having a swollen, hook-shaped body with a conical and elongate post-vulval portion ending in a round terminus, males having a weak stylet and a cylindrical and thick tail ending in a bluntly rounded and smooth terminus, and by second-stage juveniles having a slender body and a posterior body portion ending in a finely pointed or mucronate terminus. The results of glasshouse host tests indicated that the new species does not parasitise sugarcane ratoons or sour orange seedlings. Tylenchulus musicola sp. n. is distinguished from other known Tylenchulus species by the sequences of D2-D3 expansion segments of 28S rRNA and ITS rRNA genes. Phylogenetic relationships within Tylenchulus were reconstructed based on rRNA gene sequences using Bayesian inference. Diagnostic PCR-ITS-RFLP profiles are presented for T. musicola sp. n., T. furcus, T. graminis, T. palustris, T. semipenetrans and Trophotylenchulus floridensis. PCR with species-specific primers and genus-specific primer are tested and developed for rapid identification of five Tylenchulus species. An identification key to Tylenchulus species is provided.

Pratylenchus speijeri n. sp. (Nematoda: Pratylenchidae), a new root-lesion nematode pest of plantain in West Africa

Nematology ◽  
2012 ◽  
Vol 14 (8) ◽  
pp. 987-1004 ◽  
Author(s):  
Francesca De Luca ◽  
Alberto Troccoli ◽  
Larry W. Duncan ◽  
Sergei A. Subbotin ◽  
Lieven Waeyenberge ◽  
...  
Keyword(s):  
New Species ◽  
West Africa ◽  
Species Complex ◽  
Rrna Gene ◽  
28S Rrna ◽  
New Taxon ◽  
Root Lesion Nematode ◽  
Specific Primers ◽  
Lesion Nematode ◽  
Species Specific

A new root-lesion nematode, particularly pathogenic to Musa spp. and causing important plantain losses in Ghana, is described and named Pratylenchus speijeri n. sp. The cryptic status of this species within the P. coffeae species complex has been assessed and confirmed in this study. An extensive comparison of the morphological and molecular characteristics of this new species with those of P. coffeae and other related amphimictic species did not result in an unambiguous separation of this species from P. coffeae because only a few morphological features of diagnostic value were found. Sequence and phylogenetic analyses of the D2-D3 expansion segments of the 28S rRNA gene, the ITS rRNA gene and a portion of the hsp90 gene of P. speijeri n. sp. and P. coffeae species complex populations from different sources generated majority consensus BI trees with three major clades: P. speijeri n. sp. from Musa spp. roots in Ghana; unidentified or putative new Pratylenchus sp. C1 from Colocasia esculenta roots in Japan and P. coffeae with non-homogeneous relationships from different hosts and distant geographical areas. These results confirmed the validity of P. speijeri n. sp. as a new taxon and indicated that P. coffeae populations from Colocasia in Japan also need to be considered as a new species. Sequence differences in the ITS were used to design group- and species-specific primers to detect P. speijeri n. sp. and other species of P. coffeae species complex. The use of these species-specific primers for the separation of P. speijeri n. sp., Pratylenchus sp. C1 and P. coffeae has important practical application in breeding programmes for agriculture in West Africa.

A new stem nematode, Ditylenchus oncogenus n. sp. (Nematoda: Tylenchida), parasitizing sowthistle from Adriatic coast dunes in southern Italy

2015 ◽  
Vol 90 (2) ◽  
pp. 152-165 ◽  
Author(s):  
N. Vovlas ◽  
A. Troccoli ◽  
J.E. Palomares-Rius ◽  
F. De Luca ◽  
C. Cantalapiedra-Navarrete ◽  
...  
Keyword(s):  
New Species ◽  
Mitochondrial Gene ◽  
Severe Disease ◽  
Large Body ◽  
Heat Shock Protein 90 ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
28S Rrna ◽  
Protein Coding ◽  
Adriatic Coast

AbstractMorphological and molecular analyses of a stem nematode causing a severe disease on infected sowthistle (Sonchus bulbosus) plants, involving the formation of gall-like structures on infected leaves and stems, have led to the description of a new species named Ditylenchus oncogenus n. sp. Morphologically, the new species is characterized by a medium to large body size (all adults more than 1 mm in length); a delicate stylet (9.0–11.0 μm long) with minute, rounded knobs; a long post-vulval uterine sac (c. 65% of the vulva–anus distance); six incisures at the lateral fields and characteristic D. destructor-pattern of spicules (with pronounced ventral tumulus and anteriorly pointed, less sclerotized, cuticle parts present within the lamina). The results of molecular analysis of rRNA gene sequences, including the D2–D3 expansion regions of 28S rRNA, internal transcribed spacer (ITS) rRNA, partial 18S rRNA gene, the protein-coding mitochondrial gene, cytochrome oxidase c subunit I (COI), and the heat-shock protein 90 (hsp90) gene, support the new species status. The results of a host-suitability test indicated that the new species does not parasitize potato (Solanum tuberosum) tubers and broad bean (Vicia faba) seedlings. Histopathological observations on naturally infected sowthistle tissues revealed that D. oncogenus n. sp. causes floral stem neoplasia and midrib leaf gall formation on the type, and to date only known, host. The galls were characterized by extensive hyperplasia, where several necrotic cells in the neoplasic area were directly damaged by feeding of the nematode, whereas a number of adjacent cells showed typical cytological changes, such as granulated cytoplasm with hypertrophied nuclei and nucleoli.

Description of a new species of Auriculostoma (Digenea: Allocreadiidae) from Characidium heirmostigmata (Characiformes: Crenuchidae) from Argentina, using morphological and molecular data

2021 ◽  
Vol 95 ◽  
Author(s):  
M.M. Montes ◽  
J. Barneche ◽  
Y. Croci ◽  
D. Balcazar ◽  
A. Almirón ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
National Park ◽  
Molecular Data ◽  
Rrna Gene ◽  
28S Rrna ◽  
The Family ◽  
Parasitological Survey ◽  
Morphological And Molecular Data ◽  
A New Species

Abstract During a parasitological survey of fishes at Iguazu National Park, Argentina, specimens belonging to the allocreadiid genus Auriculostoma were collected from the intestine of Characidium heirmostigmata. The erection of the new species is based on a unique combination of morphological traits as well as on phylogenetic analysis. Auriculostoma guacurarii n. sp. resembles four congeneric species – Auriculostoma diagonale, Auriculostoma platense, Auriculostoma tica and Auriculostoma totonacapanensis – in having smooth and oblique testes, but can be distinguished by a combination of several morphological features, hosts association and geographic distribution. Morphologically, the new species can be distinguished from both A. diagonale and A. platense by the egg size (bigger in the first and smaller in the last); from A. tica by a shorter body length, the genital pore position and the extension of the caeca; and from A. totonacapanensis by the size of the oral and ventral sucker and the post-testicular space. Additionally, one specimen of Auriculostoma cf. stenopteri from the characid Charax stenopterus (Characiformes) from La Plata River, Argentina, was sampled and the partial 28S rRNA gene was sequenced. The phylogenetic analysis revealed that A. guacurarii n. sp. clustered with A. tica and these two as sister taxa to A. cf. stenopteri. The new species described herein is the tenth species in the genus and the first one parasitizing a member of the family Crenuchidae.

Six new species of Heteropriapulus (Monogenea: Dactylogyridae) from South American fishes with an amended diagnosis to the genus

Zootaxa ◽  
2017 ◽  
Vol 4290 (3) ◽  
pp. 459 ◽  
Author(s):  
ALINE ANGELINA ACOSTA ◽  
LIDIANE FRANCESCHINI ◽  
ALINE CRISTINA ZAGO ◽  
TOMÁŠ SCHOLZ ◽  
REINALDO JOSÉ DA SILVA
Keyword(s):  
New Species ◽  
Species Identification ◽  
Type Species ◽  
Accessory Piece ◽  
Molecular Data ◽  
Fish Host ◽  
Rrna Gene ◽  
28S Rrna ◽  
South American ◽  
Unique Shape

Heteropriapulus Kritsky, 2007 (Monogenea: Dactylogyridae), which originally included only two species from the gills of loricariid catfishes, is reviewed and six newly described species from loricariids in the Paraná River basin in Brazil are added. Diagnosis of the genus is amended and a key to the species identification is provided. Heteropriapulus anchoradiatus n. sp. from Pterygoplichthys ambrosettii (Holmberg) (Hypostominae) differs from its congeners by having a long sclerotized vagina, ventral anchors with short shaft and conspicuous superficial root, and a conspicuous and robust postero-medial process on the dorsal bar; H. bitomus n. sp. from the same fish host differs by the presence of two pairs of sclerotized patches associated with the ventral anchors; H. falxus n. sp. from Hypostomus strigaticeps (Regan) (Hypostominae) and Hypostomus ancistroides (Ihering) (Hypostominae) is unique by the shape of the accessory piece composed of two strongly sclerotized subunits; H. microcleithrus n. sp. from P. ambrosettii differs by presenting the smallest length of the dorsal bar and unique shape of the longer subunit of the accessory piece resembling the ‘hammer and sickle’ shape; H. pterygoplichthyi n. sp. from the same host presents unique shape of the longer subunit of the accessory piece of the cirrus, which is represented by ‘two sickles’ jointed by the base; and H. semitortus n. sp. from Rhinelepis aspera Spix & Agassiz (Rhinelepinae) can be distinguished by the accessory piece composed of a single straight unit and a cirrus tube with the highest number of spiral rings at the proximal end (2½). First molecular data for this genus (partial sequences of the 28S rRNA gene) are provided including the type species H. heterotylus (Jogunoori, Kritsky & Venkatanarasaiah, 2004).  

scholarly journals Taxonomical considerations and molecular phylogeny of the closely related genera Bitylenchus, Sauertylenchus and Tylenchorhynchus (Nematoda: Telotylenchinae), with one new and four known species from Iran

2020 ◽  
Vol 94 ◽  
Author(s):  
M. Hosseinvand ◽  
A. Eskandari ◽  
S. Ganjkhanloo ◽  
R. Ghaderi ◽  
P. Castillo ◽  
...  
Keyword(s):  
New Species ◽  
Anterior Part ◽  
Phylogenetic Analyses ◽  
Ribosomal Subunit ◽  
Molecular Data ◽  
28S Rrna ◽  
Natural Habitats ◽  
Morphometric Characters ◽  
Molecular Approaches ◽  
Tail Tip

Abstract During several nematological surveys in cultivated and natural habitats in Khuzestan and Zanjan provinces of Iran, a new species, Bitylenchus parvulus n. sp., two new records for Iran – namely, Tylenchorhynchus agri and Tylenchorhynchus graciliformis – and a population of Bitylenchus parvus and one of Sauertylenchus maximus were recovered and characterized based upon morphological and molecular approaches. The new species is characterized by lip region with five to seven annuli, stylet 17.7 (17.0–18.5) μm long, sub-cylindrical tail narrowing abruptly near terminus giving a bluntly digitate shape to the tail tip, cuticle near anterior part of vulva wrinkled and post-rectal sac occupies whole of tail cavity. The phylogenetic analyses were carried out using molecular data from D2–D3 expansion segments of large ribosomal subunit (28S rRNA) for all studied species and the partial small ribosomal subunit (18S rRNA) for the new species. The representatives of Bitylenchus and Sauertylenchus formed distinct clades from Tylenchorhynchus members, supporting the hypothesis in which Bitylenchus and Sauertylenchus could be considered as valid genera, but rejecting the ‘large-genus’ concept for Tylenchorhynchus. Also, Sauertylenchus ibericus was proposed as a junior synonym of S. maximus based on the results from morphological and phylogenetic analysis. Furthermore, an identification key for all known species included in the three genera Bitylenchus, Tylenchorhynchus and Sauertylenchus is presented herein. The number of transverse annuli on the lip region and presence/absence of post-rectal sac were considered as the main diagnostic characters for classifying the species into seven groups, and other morphological and morphometric characters were subsequently used for distinguishing species in each group.

scholarly journals Detection and Discrimination of Pratylenchus neglectus and P. thornei in DNA Extracts from Soil

Plant Disease ◽  
2008 ◽  
Vol 92 (11) ◽  
pp. 1480-1487 ◽  
Author(s):  
Guiping Yan ◽  
Richard W. Smiley ◽  
Patricia A. Okubara ◽  
Andrea Skantar ◽  
Sandra A. Easley ◽  
...  
Keyword(s):  
Nematode Species ◽  
Wheat Root ◽  
Fungal Species ◽  
Parasitic Nematodes ◽  
Rrna Gene ◽  
28S Rrna ◽  
Pratylenchus Neglectus ◽  
Pcr Products ◽  
Species Specific ◽  
Plant Parasitic

A species-specific polymerase chain reaction (PCR) method was developed to detect and identify the root-lesion nematodes Pratylenchus neglectus and P. thornei from soil. A primer set was designed from Pratylenchus 28S rRNA gene sequences of the D3 expansion domain. Primer specificity was confirmed with 23 isolates of 15 nematode species and other plant-parasitic and non-plant-parasitic nematodes typically present in the soil communities, and with six fungal species commonly associated with wheat root rot. DNA obtained using a commercially available kit and a method developed in our laboratory gave comparable amplification. PCR conditions were optimized and the two species were differentiated by PCR products of 144 bp for P. neglectus and 288 bp for P. thornei. With this assay, we detected a single juvenile in 1 g of sterile, inoculated soil. Examination of 30 field soil samples revealed that this method was applicable to a range of soils naturally infested with these two pathogens in Oregon. This PCR-based method is rapid, efficient, and reliable, does not require expertise in nematode taxonomy and morphology, and could be used as a rapid diagnostic tool for commercial and research applications for disease forecasting and management.

scholarly journals Molecular and morphological characterisation of Xiphinema granatum n. sp. and Longidorus pisi Edward, Misra & Singh, 1964 (Dorylaimida: Longidoridae) from Iran

Nematology ◽  
2012 ◽  
Vol 14 (8) ◽  
pp. 949-960 ◽  
Author(s):  
Majid Pedram ◽  
Ebrahim Pourjam ◽  
Juan E. Palomares-Rius ◽  
Razieh Ghaemi ◽  
Carolina Cantalapiedra-Navarrete ◽  
...  
Keyword(s):  
New Species ◽  
Species Group ◽  
Rrna Gene ◽  
28S Rrna ◽  
Morphometric Data ◽  
Molecular Analyses ◽  
Morphological Characterisation ◽  
28S Rrna Gene ◽  
Close Relationship ◽  
Female Genital

Xiphinema granatum n. sp. from pomegranate in Saveh, Markazi province, central Iran, is described and illustrated. The new species belongs to species group 8 of the genus Xiphinema sensu Loof & Luc, 1990. The new species is characterised by a body 3.5-4.1 mm long, 37-49 μm diam., odontostyle and odontophore 118-132 and 65-74 μm long, respectively, presence of sperm in the female genital tracts, uterus devoid of any Z-differentiation or spines, and abundant males with spicules 45-58 μm long. The polytomous identification codes of the new species are: A4, B4, C5a, D5, E56, F4, G23, H2, I3, J4, K2, L2. Beside morphological and morphometric data, molecular analyses of D2-D3 fragments of 28S rRNA gene placed the new species in close relationship with X. vuittenezi and X. italiae and some species belonging to Xiphinema morphospecies group 6, but clearly separated from X. index. In addition, an Iranian population of Longidorus pisi from the same locality is morphologically and molecularly characterised.

Morphological and molecular characterization of cucullanid nematodes including Cucullanus opisthoporus n. sp. in freshwater fish from the Brazilian Amazon

2016 ◽  
Vol 91 (6) ◽  
pp. 739-751 ◽  
Author(s):  
F.B. Pereira ◽  
J.L. Luque
Keyword(s):  
New Species ◽  
Freshwater Fish ◽  
Original Description ◽  
Morphological Characterization ◽  
Rrna Genes ◽  
28S Rrna ◽  
Type Specimens ◽  
Tail Tip ◽  
First Time

AbstractMolecular and morphological characterization of two species of Cucullanidae from freshwater fish in Brazil are provided, one of which represented an undescribed taxon. Cucullanus opisthoporus n. sp. was collected in Cichla melaniae from River Xingu, State of Pará, and in C. pinima from River Jamarí, State of Rondônia. Nematodes referable to Cucullanus grandistomis were collected in Oxydoras niger from River Xingu. The new species has an appendage in the tail tip, ventrally covered by small spines, which is an exclusive feature of Cucullanus tucunarensis. However, C. tucunarensis differs from C. opisthoporus n. sp. based upon the relative position of deirids and the excretory pore, which are more posterior from the oesophageal end in the new species. Observations of C. tucunarensis type specimens also revealed features that were wrongly or not reported in the original description. Type specimens of C. grandistomis were observed, although they were poorly preserved. After evaluation of newly collected specimens of C. grandistomis, features unreported in the original description were observed for the first time, including the presence of an intestinal caecum. Thus, C. grandistomis was transferred to Dichelyne. Sequences of the 18S and 28S rRNA genes revealed high genetic similarity between the specimens of C. opisthoporus n. sp. from the two different hosts as well as their genetic distance from Dichelyne grandistomis n. comb. Phylogenetic reconstructions using representatives of Cucullanidae suggested the artificiality of the current morphological system adopted to separate the genera, since most genera were not monophyletic, although the availability of genetic data is still fragmented.

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