Heterorhabditis atacamensis n. sp. (Nematoda: Heterorhabditidae), a new entomopathogenic nematode from the Atacama Desert, Chile

AbstractA new Heterorhabditis species of entomopathogenic nematode was isolated from soil of the Atacama Desert in Chile. The new species is characterized by morphometrics of the infective juvenile (IJ) with length (L) = 611 (578–666) μm, head to excretory pore length (EP) = 115 (101–126) μm, tail = 69 (62–79) μm long, (EP/tail) × 100 (E%) = 165 (149–182) and L/maximum body diameter (ratio a) = 28 (25–31). The male has spicules 45 (40–49) μm long, gubernaculum 20 (17–22) μm long and (spicule length/anal body diameter) × 100 (SW%) = 205 (179–249). The hermaphroditic adult has shallow cuticular folds immediately anterior and posterior to the vulva, a slight post-anal swelling and a finely rounded tail terminus. Morphologically, H. atacamensis n. sp. resembles H. safricana, H. marelatus, H. downesi and H. amazonensis, but can be distinguished by characters of adult and IJ stages. In particular, for adult males, H. atacamensis n. sp. differs from H. amazonensis by the number and orientation of the genital papillae and from H. downesi by the position of the excretory pore; by the shape of the female tail terminus from H. downesi and by the position of the IJ hemizonid from H. marelatus. Heterorhabditis atacamensis n. sp. is further characterized by internal transcribed spacer (ITS) and D2D3 rDNA sequences, the closest species, H. safricana, being separated by 13 bp across 730 bp of the ITS (incorporating ITS1 (partial sequence), 5.8S (complete sequence), ITS2 (complete sequence)) and 5 bp across 592 bp of the partial 28S (incorporating D2D3) sequence. The morphological and molecular data confirm that H. atacamensis n. sp. is a valid species.

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A new entomopathogenic nematode, Steinernema colombiense n. sp. (Nematoda: Steinernematidae), from Colombia

Nematology ◽

10.1163/156854108784513879 ◽

2008 ◽

Vol 10 (4) ◽

pp. 561-574 ◽

Cited By ~ 10

Author(s):

Juan Carlos López-Núñez ◽

Kathryn Plichta ◽

Carmenza E. Góngora-Botero ◽

S. Patricia Stock

Keyword(s):

Excretory Pore ◽

Sequence Data ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Rdna Sequence ◽

Its Rdna ◽

Infective Juvenile ◽

Diagnostic Features ◽

Rdna Sequences ◽

Rdna Sequence Data

Abstract A new entomopathogenic nematode, Steinernema colombiense n. sp., is described from Colombia. Morphological, molecular (28S and ITS rDNA sequence data) and cross-hybridisation studies were used for diagnostics and identification purposes. In addition, 28S and ITS rDNA sequence data were used to assess evolutionary relationships of the new species with other Steinernema spp. Morphological diagnostic features for S. colombiense n. sp. include morphometric features of the third-stage infective juvenile, including body length of 636 (549-732) μm, narrow body diam. (31 (22-36) μm), position of the excretory pore (35 (31-40) μm), tail length (41 (32-53) μm), D% = 29 (25-33) and E% = 205 (138-284). In addition, males of first and second generations are characterised by the morphology of the spicules and gubernaculum, the number and arrangement of the genital papillae and the excretory pore position (at 67 (56-76) and 54 (46-63) μm, for first and second generations, respectively). In addition to these traits, 28S and ITS rDNA sequences analyses both showed this species to be a distinct and unique entity.

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Steinernema ashiuense sp. n. (Nematoda: Steinernematidae), a new entomopathogenic nematode from Japan

Nematology ◽

10.1163/156854106778877901 ◽

2006 ◽

Vol 8 (5) ◽

pp. 681-690 ◽

Cited By ~ 10

Author(s):

Long K. Phan ◽

Shuhei Takemoto ◽

Kazuyoshi Futai

Keyword(s):

New Species ◽

Body Length ◽

Excretory Pore ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Morphological Characters ◽

Rdna Sequence ◽

Infective Juvenile ◽

Lateral Field ◽

Spicule Length

Abstract Steinernema ashiuense sp. n. was collected by a Galleria baiting method from grassland along the riverbank of the Yura river, near the Ashiu Research Forest Station of Kyoto University. The new species is characterised by an infective juvenile body length of 768 (720-800) μm, lateral field with five equally developed ridges (i.e., six lines or incisures), head smooth lacking horn-like structures, excretory pore located at level of middle of pharynx, hyaline portion short (ca one-third of tail length). Males have 50-65 μm long, broad, slightly yellowish spicules; spicule length / spicule width = 4 (3.5-4.4), and two subventral and one subdorsal pair of genital papillae in the postcloacal region. The analysis of ITS-rDNA sequence placed S. ashiuense sp. n. in the 'feltiae-kraussei-oregonense' group in the clade containing S. robustispiculum and S. monticolum. It can be distinguished from these species by morphological characters of the infective juveniles and males.

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Steinernema australe n. sp. (Panagrolaimomorpha: Steinernematidae), a new entomopathogenic nematode from Isla Magdalena, Chile

Nematology ◽

10.1163/156854108x399326 ◽

2009 ◽

Vol 11 (5) ◽

pp. 699-717 ◽

Cited By ~ 7

Author(s):

Steve Edgington ◽

Alan G. Buddie ◽

Lukasz Tymo ◽

David J. Hunt ◽

Khuong B. Nguyen ◽

...

Keyword(s):

New Species ◽

First Generation ◽

Entomopathogenic Nematode ◽

Valid Species ◽

Infective Juvenile ◽

Long Tail ◽

The Pacific ◽

The Pacific Ocean ◽

H 51 ◽

Tail Tip

Abstract A new species of entomopathogenic nematode, Steinernema australe n. sp., was isolated from a soil sample taken close to the beach on Isla Magdalena, an island in the Pacific Ocean, 2 km from mainland Chile. Morphologically the new species belongs to the glaseri-group and is characterised by morphometrics of the infective juvenile which has a very long body of 1316 (1162-1484) μm, excretory pore located far posterior to the anterior extremity (110 (95-125) μm), exceptionally long tail of 103 (92-114) μm, H% = 51 (42-61), E% = 107 (94-122) and a ratio = 35 (31-38). The first generation male has 72 (55-78) μm long spicules, a 45 (36-51) μm long gubernaculum and SW% = 172 (118-196). The first generation female can be recognised by well developed double epiptygmata, the lack of a prominent postanal swelling, a mucron on the tail tip and (in 60% of individuals) one to two subsidiary mucrons. Sequences of the ITS and D2D3 regions of the ribosomal DNA confirm that S. australe n. sp. is a valid species.

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Steinernema texanum n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Texas, USA

Nematology ◽

10.1163/156854107781352025 ◽

2007 ◽

Vol 9 (3) ◽

pp. 379-396 ◽

Cited By ~ 6

Author(s):

Robin Stuart ◽

Ugur Gozel ◽

Khuong Nguyen ◽

Michael Rogers ◽

Vanessa Andalo

Keyword(s):

New Species ◽

Excretory Pore ◽

Entomopathogenic Nematode ◽

Its Region ◽

Ventral Side ◽

Infective Juvenile ◽

Sequence Length ◽

Field Pattern ◽

Lateral Field ◽

Tail Tip

AbstractSteinernema texanum n. sp. is characterised by morphometrics of the infective juvenile with body length = 756 μm, distance from anterior end to the excretory pore = 59 μm, tail = 73 μm, ratio a = 25, H% = 59 and E% = 81. The lateral field pattern of the new species is 2, 7, 2, and is typical for the species. The male of the first generation can be recognised by the spicule and the gubernaculum lengths and shapes, position of the excretory pore, D% = 67 and GS% = 75. The female can be recognised by the vulva with very low epiptygma and two wart-like structures anterior to the tail tip that are always present on the ventral side. Steinernema texanum n. sp. is characterised genetically by the sequence of the ITS region (sequence length = 956 bp, the length of ITS1 = 263 bp, ITS2 = 286 bp, composition of its sequence and by 18 autapomorphies) and by sequence of D2D3 regions (sequence length = 860 bp, its composition and 15 autapomorphies). Steinernema texanum n. sp. is closely related to species in the feltiae-group, which include S. akhursti, S. feltiae, S. hebeiense, S. jollieti, S. kraussei, S. kushidai, S. litorale, S. monticolum, S. oregonense, S. sangi, S. silvaticum and S. weiseri. Isolates of the new species were obtained using the Galleria-baiting technique from soil samples taken near Kingsville, Texas, USA.

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Steinernema khoisanae n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa

Nematology ◽

10.1163/156854106777998728 ◽

2006 ◽

Vol 8 (2) ◽

pp. 157-175 ◽

Cited By ~ 37

Author(s):

Antoinette Malan ◽

Ugur Gozel ◽

Khuong Nguyen

Keyword(s):

South Africa ◽

New Species ◽

Excretory Pore ◽

Phylogenetic Trees ◽

First Generation ◽

Entomopathogenic Nematode ◽

Internal Transcribed Spacers ◽

Infective Juvenile ◽

Field Pattern ◽

Lateral Field

AbstractA new species of entomopathogenic nematode, Steinernema khoisanae n. sp. is described from South Africa. The new species is characterised by morphometrics of the infective juvenile with body length 1076 μm, narrow body diameter of 33 μm, excretory pore 94 μm from anterior end, tail 85 μm long, a = 33, D% = 68, H% = 57, and E% = 111. The lateral field pattern of the new species is 2, 7, 8, 6, 4 and 2. The male of the first generation can be recognised by the spicule and the gubernaculum shape, excretory pore located posteriorly near the end of the pharynx, D% = 88, and SW% = 199. The first generation female can be recognised by the non-protruding vulva and tail bearing a prominent mucron. Steinernema khoisanae n. sp. is characterised genetically by sequences of the internal transcribed spacers and D2/D3 regions of 28S ribosomal DNA, by composition of their sequences and by numerous unique, derived, nucleotide character states. Phylogenetic trees show that S. khoisanae n. sp. and other members of the S. glaseri-group form a monophyletic assemblage.

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Morphology, molecular profiles and distribution of Japanese populations of Steinernema tielingense Ma, Chen, Li, Han, Khatri-Chhetri, De Clercq & Moens, 2012 (Rhabditida: Steinernematidae)

Nematology ◽

10.1163/15685411-bja10085 ◽

2021 ◽

pp. 1-20

Author(s):

Yasuharu Mamiya ◽

Mitsuteru Akiba ◽

Taisuke Ekino ◽

Natsumi Kanzaki

Keyword(s):

Symbiotic Bacterium ◽

Original Description ◽

Molecular Data ◽

Infective Juvenile ◽

Chinese Isolate ◽

Molecular Characteristics ◽

Japanese Isolate ◽

Adult Males ◽

Type Population ◽

Molecular Profiles

Summary Steinernema tielingense was found to be widely distributed in Japan. The molecular characteristics of the nematodes isolated from Japan are basically in accordance with those mentioned in the original description of S. tielingense. However, the Japanese isolates are morphologically distinct from the type population by the following characters: length of the infective juvenile, 711 (671-769) μm, excretory pore of adult males and infective juveniles located posterior mid-pharynx, D% < 50%, smaller H value of 35% and shorter spicules in adult males of both generations. Although discrepancies in morphology and morphometric data between the Chinese isolate and Japanese isolate were observed, the molecular data matched and on this basis the Japanese isolate was identified as being conspecific with S. tielingense. The symbiotic bacterium isolated from the Japanese population of S. tielingense was identified as Xenorhabdus bovienii.

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Morphological, Molecular and Ecological Characterization of a Native Isolate of Steinernema Feltiae (Rhabditida: Steinernematidae) From Southern Chile

10.21203/rs.3.rs-72852/v1 ◽

2020 ◽

Author(s):

Patricia A Flores ◽

Andrea Alvarado ◽

Gabriela O. Lankin ◽

Paola Lax ◽

Simona Prodan ◽

...

Keyword(s):

Galleria Mellonella ◽

Entomopathogenic Nematode ◽

Intraspecific Variability ◽

Field Capacity ◽

Molecular Data ◽

Water Levels ◽

Steinernema Feltiae ◽

Infective Juvenile ◽

Ecological Characteristics ◽

Control Programs

Abstract Background: Steinernema feltiae is an entomopathogenic nematode used in biological control programs with a global distribution. It has been shown that populations of S. feltiae may have phenotypic plasticity derived from local adaptation and may vary in different traits, such as location and penetration of the host. This is the first time that a Chilean isolate has been described in detail, taking into account morphological, molecular and ecological characteristics. Methods: S. fealtiae was detected a few years ago in southern regions of Chile in the town Lican Ray and was morphologically and morphometrically described, along with a molecular description based on the ITS and D2-D3 regions. Some ecological characteristics were determined, including the temperature requirements for completion of its life cycle and the effect of three water levels in soil for optimal reproduction. Results: Morphometric characteristics of different life stages show large intraspecific variability in averages and ranks compared with isolates from different geographical origins. The molecular data also show intraspecific variability with respect to other isolates. The lower, optimal and higher temperatures found to limit the infestation and reproduction of Galleria mellonella were 10, 20 and 30 °C respectively, and emergence from the host larvae occurred approximately ten days after inoculation. Differences were observed in offspring emerging from the host, and the 120 infective juveniles (IJ)/larvae dose was the most prolific at 20 °C. The water content of the soil did not affect the number of infective juvenile invaders, penetration efficacy (%), and time of emergence of the IJ or offspring per larvae, but it caused a delay in achieving full mortality at the permanent wilting point with respect to saturation and field capacity.Conclusions: Data obtained in this study are valuable since they outline some environmental requirements of this strain to perform optimally in the event of being used as a soil pest bioantagonist.

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Redescription and synonymization of Oscheius citri Tabassum, Shahina, Nasira and Erum, 2016 (Rhabditida, Rhabditidae) from India and its taxonomical consequences

Journal of Helminthology ◽

10.1017/s0022149x21000134 ◽

2021 ◽

Vol 95 ◽

Author(s):

A. Rana ◽

A.H. Bhat ◽

A.K. Chaubey ◽

V. Půža ◽

J. Abolafia

Keyword(s):

Indian Population ◽

Uttar Pradesh ◽

Nematode Species ◽

Molecular Data ◽

Molecular Characteristics ◽

Morphometric Characteristics ◽

High Similarity ◽

Rdna Sequences ◽

Indian Strain ◽

28S Rdna Sequences

Abstract A population of a nematode species belonging to the genus Oscheius was isolated in western Uttar Pradesh, India. Morphological and morphometrical studies on this species showed its high similarity with six species described previously from Pakistan (Oscheius citri, O. cobbi, O. cynodonti, O. esculentus, O. punctatus and O. sacchari). The molecular analysis of the ITS1-5.8S-ITS2 rDNA sequences of the Indian population and the six species described from Pakistan showed that all the sequences are almost identical. Thus, based on morphological and molecular characteristics, all of the six above-mentioned Pakistani species and Indian strain do not differ from each other, hence can be considered synonyms. The correct name for this taxon is the first described species O. citri. Additionally, the phylogenetic analysis of the 18S rDNA and the 28S rDNA sequences showed that Oscheius citri is sister to the clade formed by O. chongmingensis and O. rugaoensis from China. The high similarity of morphological and morphometric characteristics of O. citri and other species, O. maqbooli, O. nadarajani, O. niazii, O. shamimi and O. siddiqii, suggest their conspecificity; however, lack of molecular data for these species does not allow this hypothesis to be tested.

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Two new species of Paurodontella Husain & Khan, 1968 (Nematoda: Sphaerulariidae) associated with wheat and a diagnostic compendium to the genus

Nematology ◽

10.1163/156854109x461730 ◽

2010 ◽

Vol 12 (2) ◽

pp. 181-192 ◽

Cited By ~ 6

Author(s):

Zafar A. Handoo ◽

Erum Y. Iqbal ◽

Nasira Kazi ◽

Shahina Fayyaz

Keyword(s):

Triticum Aestivum ◽

New Species ◽

Excretory Pore ◽

Triticum Aestivum L ◽

Slender Body ◽

Valid Species ◽

Lateral Field ◽

North West ◽

North West Frontier Province ◽

Two New Species

Abstract An identification key to ten valid species of Paurodontella is given. A compendium of the most important diagnostic characters with illustrations of each species is included as a practical alternative and supplement to the key. The diagnosis of Paurodontella is emended and a list of all valid species of the genus is given. Two new species (Paurodontella myceliophaga n. sp. and P. balochistanica n. sp.) collected around the roots of wheat (Triticum aestivum L.) from North-West Frontier Province and Balochistan, Pakistan, are described and illustrated. Paurodontella myceliophaga n. sp. is characterised by having a short post-uterine sac, lateral field with four incisures, excretory pore at the base of the pharynx and fusiform median bulb, whereas P. balochistanica n. sp. has a longer and very slender body with posterior vulva, lateral field with four incisures and short mucronate tail. Because these species are limited in distribution, their importance is not known.

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Morphological and molecular characterisation of Aporcelaimellus simplex (Thorne & Swanger, 1936) Loof & Coomans, 1970 and a new concept for Aporcella Andrássy, 2002 (Dorylaimida: Aporcelaimidae)

Nematology ◽

10.1163/156854112x651320 ◽

2013 ◽

Vol 15 (2) ◽

pp. 165-178 ◽

Cited By ~ 6

Author(s):

Sergio Álvarez-Ortega ◽

Sergei A. Subbotin ◽

Reyes Peña-Santiago

Keyword(s):

Molecular Data ◽

Evolutionary Tree ◽

Valid Species ◽

Molecular Characterisation ◽

New Combinations ◽

Terminal Portion ◽

Significant Difference ◽

European Populations ◽

Emended Diagnosis

This contribution presents a study of Iberian and Californian populations of Aporcelaimellus simplex, including morphological, morphometric and molecular data. The species is characterised and distinguished by its lip region offset by an expansion, pars refringens vaginae absent, and conical tail with a small but distinct hyaline terminal portion. No significant difference exists between American and European populations. Molecular data and the derived evolutionary tree show a topology in which this species forms a well-supported group with members of Discolaiminae, far from other representatives of Aporcelaimellus. Putting special emphasis in the absence of pars refringens vaginae, A. simplex is transferred to the genus Aporcella. The taxonomy of this genus is revised in depth, with the proposal of an emended diagnosis, the provision of a list of 13 valid species (mostly new combinations from Aporcelaimellus) as well as a key to their identification and a compendium of their main morphometrics. Aporcella debruinae sp. n. is proposed for Aporcelaimellus papillatus apud de Bruin & Heyns, 1992.

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