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

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

Nematology ◽

10.1163/138855410x535714 ◽

2011 ◽

Vol 13 (5) ◽

pp. 569-587 ◽

Cited By ~ 14

Author(s):

Nomakholwa F. Stokwe ◽

Antoinette P. Malan ◽

Khuong B. Nguyen ◽

Rinus Knoetze ◽

Louwrens Tiedt

Keyword(s):

South Africa ◽

New Species ◽

Body Length ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Morphological Characters ◽

The Body ◽

Infective Juvenile ◽

Western Cape ◽

Citrus Orchards

Abstract During a survey for entomopathogenic nematodes in citrus orchards throughout South Africa, a new species of Steinernema was isolated from a citrus orchard on Rietkloof farm, near the town of Piketberg in the Western Cape Province, South Africa. The nematode was isolated from soil using the Galleria-baiting technique. Steinernema citrae n. sp. is characterised by the following morphological characters: third-stage infective juvenile with a body length of 754 (623-849) μm, distance from head to excretory pore of 56 (49-64) μm, tail length of 71 (63-81) μm, and ratio E value of 110 (85-132). The lateral pattern for the new species is 2, 7, 8, 6, 4, 2 and is not typical for the genus. Steinernema citrae n. sp. is closely related the feltiae-group. The body length of the IJ is close to that of S. texanum and S. weiseri, though it differs in body diam., the length of the pharynx and E%. The male of S. citrae n. sp. differs from S. feltiae in the length and shape of the spicule and body diam. Steinernema citrae n. sp. differs from all species in the feltiae-group in the morphology of the vulva, as it has a single flapped, low, epiptygma. It also differs from the most closely related species, S. feltiae, as there is no interbreeding between the two species. In addition, the new nematode differs from other species of the feltiae-group by characteristics of the ITS and D2D3 regions of its rDNA.

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A new entomopathogenic nematode, Steinernema xinbinense n. sp. (Nematoda: Steinernematidae), from north China

Nematology ◽

10.1163/156854112x627273 ◽

2012 ◽

Vol 14 (6) ◽

pp. 723-739 ◽

Cited By ~ 5

Author(s):

Juan Ma ◽

Shulong Chen ◽

Juan Ma ◽

Shulong Chen ◽

...

Keyword(s):

New Species ◽

Dna Sequences ◽

First Generation ◽

Galleria Mellonella ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Northern China ◽

Morphological Characters ◽

Liaoning Province ◽

Lateral Field

During a survey for entomopathogenic nematodes in northern China, a new species of Steinernema was isolated from soil samples collected from Xinbin county, Liaoning province. This nematode was obtained by the insect-baiting technique using last instar larvae of Galleria mellonella. It is described herein as S. xinbinense n. sp. The nematode can be separated from other described species of the group by morphological and morphometric characteristics of the different stages and by characterisation and phylogeny of DNA sequences of the D2D3 domain of the LSU or ITS regions of rDNA. This new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 694 (635-744) μm, distance from head to excretory pore of 51 (46-53) μm, tail length of 73 (61-81) μm, E = 71 (65-78)%, presence of eight unevenly spaced and developed ridges in middle lateral field (i.e., nine lines). First generation male with well curved, yellowish spicules 56 (49-62) μm long and gubernaculum 35 (30-41) μm long, small mucron mostly present, first generation female with protruding vulva, tail conical with one or two small mucrons and D = 45 (41-50)%. Cross hybridisation tests with S. tielingense, S. kraussei, S. feltiae and S. hebeiense showed that this species was reproductively isolated. The analyses of ITS-rDNA and D2D3 sequence confirm that the studied nematode isolate is a valid new species belonging to the ‘feltiae-kraussei-oregonense’ group.

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

Nematology ◽

10.1163/15685411-00002978 ◽

2016 ◽

Vol 18 (5) ◽

pp. 571-590 ◽

Cited By ~ 7

Author(s):

Antoinette P. Malan ◽

Rinus Knoetze ◽

Louwrens R. Tiedt

Keyword(s):

South Africa ◽

New Species ◽

Ribosomal Dna ◽

First Generation ◽

Entomopathogenic Nematode ◽

Infective Juvenile ◽

Lateral Field ◽

Spicule Length ◽

Molecular Features ◽

Generation Female

Steinernema nguyenin. sp. was recovered by baiting from beneath anOlea africanatree in South Africa. The combination of morphological and molecular features suggests thatS. nguyenin. sp. is a member of thefeltiae-kraussei-oregonensegroup, clustering with members of this group in Clade III. The new species is morphologically characterised by the infective juvenile body length of 737 (673-796) μm and the number of ridges in the infective juvenile lateral field is 2, 8, 2. The male of the first generation can be recognised by the spicule length of 66 (58-75) μm and a gubernaculum length of 43 (30-55) μm. The first generation female can be recognised by the vulval lips only slightly protruding and the presence of low, double-flapped epiptygmata. Analysis of the ITS and D2-D3 regions of the ribosomal DNA confirms thatS. nguyenin. sp. differs from all other knownSteinernemaspecies.

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A new entomopathogenic nematode, Steinernema hebeiense sp. n. (Rhabditida: Steinernematidae), from North China

Nematology ◽

10.1163/156854106778614056 ◽

2006 ◽

Vol 8 (4) ◽

pp. 563-574 ◽

Cited By ~ 4

Author(s):

Maurice Moens ◽

Sergei Spiridonov ◽

Aihua Yan ◽

Shulong Chen ◽

Xiuhua Li

Keyword(s):

New Species ◽

Body Length ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Total Body Length ◽

Molecular Data ◽

Body Region ◽

Lsu Rdna ◽

Lateral Field ◽

Total Body

AbstractA new species of Steinernema (Rhabditida), S. hebeiense sp. n. was isolated from sandy soil, Hebei Province, China. Diagnostic characters of infective juveniles of S. hebeiense sp. n. include total body length of 658 (610-710) μm, distance from anterior end to excretory pore of 48 (43-51) μm, tail length of 66 (63-71) μm, and E% ratio of 72 (65-80). The lateral field has eight ridges at the mid-body region (two very thin submarginal ridges, poorly discernible under light microscope, but visible in SEM); and the anterior end is slightly offset and flattened. First generation males have a body length of 1177 (1036-1450) μm, spicule length = 57 (51-63) μm, and gubernaculum length = 46 (38-50) μm. The spicules are light brown in colour and slightly curved; the manubrium is longer than wide. A tail mucron is present in second generation males. These morphometrical and morphometric features classify S. hebeiense sp. n. within the ' feltiae-kraussei-oregonense ' group. Molecular data also classify the new species within this group. Within this group, the smallest differences between the sequences of S. hebeiense sp. n. is with S. weiseri – 73 bp in the ITS rDNA and 13 bp in the studied partial sequence of the D2D3 expansion segment of LSU rDNA.

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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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Steinernema litorale n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Japan

Nematology ◽

10.1163/1568541044038650 ◽

2004 ◽

Vol 6 (6) ◽

pp. 819-838 ◽

Cited By ~ 13

Author(s):

Mutsuhiro Yoshida

Keyword(s):

New Species ◽

First Generation ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Morphological Characters ◽

Similar Species ◽

Lateral Field ◽

Third Stage ◽

Stage Juvenile ◽

Generation Male

AbstractA new entomopathogenic nematode, Steinernema litorale n. sp., was isolated from sandy soils in Cape Irago, Atsumi Peninsula, Aichi, Honshu Island, Japan. The new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 909 ± 42.1 (834–988) μm, distance from head to excretory pore of 61 ± 3.3 (54–69) μm, tail length of 83 ± 4.5 (72–91) μm, ratio E value of 0.73 (0.68–0.83) and lateral field with nine distinct lines; male tail with a mucron in both generations, spicule shape (moderately arcuate, heavy, spicule with elongated manubrium), spicule length of 75 ± 4.8 (67–89) μm and gubernaculum length of 53 ± 4.0 (44–64) μm in the first generation male; female vulva with a double-flapped epiptygma and a tail with a pointed tip in both generations, and ratio D value of 45.2 (33.3–56.8) in the first generation female. The new species was distinguished from the morphologically similar species, S. feltiae, S. thanhi, S. karii, S. scarabaei, S. kraussei, S. oregonense, S. loci and S. diaprepesi by RFLP profiles. Morphological and molecular studies indicated that S. litorale n. sp. was phenotypically most similar to S. feltiae. However, cross hybridisation tests demonstrated that the two species were reproductively isolated.

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Steinernema huense sp. n., a new entomopathogenic nematode (Nematoda: Steinernematidae) from Vietnam

Nematology ◽

10.1163/15685411-00002806 ◽

2014 ◽

Vol 16 (7) ◽

pp. 761-775 ◽

Cited By ~ 5

Author(s):

Ke Long Phan ◽

Zdeněk Mráček ◽

Vladimír Půža ◽

Jiří Nermut ◽

Andrea Jarošová

Keyword(s):

New Species ◽

National Park ◽

First Generation ◽

Entomopathogenic Nematode ◽

Tail Length ◽

Symbiotic Bacterium ◽

Molecular Data ◽

Lateral Field ◽

Spicule Length ◽

Short Body

A new entomopathogenic nematode, Steinernema huense sp. n., belonging to the carpocapsae group, was recovered in Bach Ma National Park (Thua Thien Hue province) Vietnam. Steinernema huense sp. n. infective juveniles are characterised by short body length of 527 (444-571) μm, distance from anterior end to excretory pore of 43 (38-46) μm, anterior end to end of pharynx of 116 (103-129) μm; tail length of 50 (43-56) μm, D% = 37 (34-39) and E% = 85 (79-93), H% = 44 (39-52) and in having six ridges (i.e., seven lines) in the lateral field. For first generation males, the diagnostic characters include the spicule length of 67 (60-72) μm; D% = 48 (41-61); SW% = 195 (168-238) and GS% = 76 (68-81). Both generations possess a minute filamentous mucron, which can be rudimentary in the first generation, and 23 genital papillae. Spicules are finely curved, brownish and slender with a prominent rostrum. First generation females have a non-protruding, symmetrical vulva, with double flapped epiptygma. The tail of mature females is obese with a short conical tip (peg) lacking minute protuberances, and post-anal swelling not developed. The new species is further characterised by sequences of ITS and D2-D3 regions of the ribosomal DNA. According to molecular data, the symbiotic bacterium of S. huense sp. n. is closely related to Xenorhabdus stockiae.

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Steinernema kandii n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from northern Benin

Nematology ◽

10.1163/15685411-00003201 ◽

2019 ◽

Vol 21 (2) ◽

pp. 107-128 ◽

Cited By ~ 1

Author(s):

Anique Godjo ◽

Leonard Afouda ◽

Hugues Baimey ◽

Marjolein Couvreur ◽

Lionel Zadji ◽

...

Keyword(s):

New Species ◽

Body Length ◽

Entomopathogenic Nematode ◽

Phylogenetic Analyses ◽

28S Rdna ◽

Infective Juvenile ◽

Type Isolate ◽

Spicule Length ◽

A New Species

Summary Two nematode isolates from the genus Steinernema were collected in northern Benin. Morphological, morphometric, molecular and cross-hybridisation studies placed these nematodes into a new species, Steinernema kandii n. sp., within the bicornutum-group. Phylogenetic analyses based on both ITS and D2-D3 regions of 28S rDNA revealed that S. kandii n. sp. is different from all known Steinernema species and sister to S. abbasi (97.3-97.6% ITS nucleotide similarity) and S. bifurcatum (98.3-98.4% D2-D3 similarity). Steinernema kandii n. sp. can be separated from other members of the bicornutum-group by the greater infective juvenile (IJ) max. body diam. of 35 (27-48) μm (type isolate). It differs from S. abbasi by the greater IJ body length 707 (632-833) μm (type isolate), EP distance 55 (52-60) μm (type isolate), spicule length 67 (57-75) μm (type isolate) and the occurrence of one pair of genital papillae at the cloacal aperture.

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