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

Nematology ◽  
2020 ◽  
Vol 22 (3) ◽  
pp. 343-360 ◽  
Author(s):  
Agil Katumanyane ◽  
Antoinette P. Malan ◽  
Louwrens R. Tiedt ◽  
Brett P. Hurley
Keyword(s):  
South Africa ◽  
New Species ◽  
First Generation ◽  
Second Generation ◽  
Entomopathogenic Nematode ◽  
Infective Juvenile ◽  
African Continent ◽  
Generation Male

Summary Two isolates of Steinernema bertusi n. sp. were separately recovered from Tito, Mpumalanga, and Port Edward, Kwa Zulu Natal, South Africa. In this paper, we describe the isolates as a new entomopathogenic nematode (EPN) species using molecular and morphological methodologies. The new species belongs to the cameroonense-clade, which consists of nematodes only isolated from the African continent. Steinernema bertusi n. sp. is characterised by having the longest infective juvenile (IJ) for this clade at 716 (628-814) μm. The IJ is further characterised by a body diam. of 32 (28-36) μm and the pattern for the arrangement of the lateral ridges from head to tail is 2, 4, 5, 4, 2. The first-generation male spicule and gubernaculum length is 82 (72-88) μm and 63 (54-72) μm, respectively. Only 25% of the second-generation males possess a mucron. The first-generation females of S. bertusi n. sp. have a slightly protruding vulva, with double-flapped epiptygmata and a mucron at the posterior end. The new EPN species is most closely related to S. sacchari and is the sixth species to be included in the cameroonense-clade.

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

Nematology ◽  
2014 ◽  
Vol 16 (4) ◽  
pp. 475-494 ◽  
Author(s):  
Isaiah Nthenga ◽  
Rinus Knoetze ◽  
Shaun Berry ◽  
Louwrens R. Tiedt ◽  
Antoinette P. Malan
Keyword(s):  
South Africa ◽  
New Species ◽  
Sugar Cane ◽  
First Generation ◽  
Entomopathogenic Nematode ◽  
Tail Length ◽  
Infective Juvenile ◽  
Eldana Saccharina ◽  
Lateral Field ◽  
Generation Male

A new species of entomopathogenic nematode, Steinernema sacchari n. sp., was isolated by trapping with the sugar cane borer, Eldana saccharina, from soil of a sugar cane field in the KwaZulu-Natal province of South Africa. The new species is morphologically characterised by the length of the infective juvenile (IJ) of 680 (630-722) μm, tail length of 64 (51-74) μm, ratio a = 19 (14-23), H% = 49 (43-57) and E% = 82 (70-109). The pattern of the lateral field of the IJ of the new species is 2, 5, 2 ridges (3, 6, 3 lines or incisures). The male of the first generation can be recognised by the long spicule of 83 (73-89) μm, gubernaculum of 61 (50-68) μm, D% = 67 (54-88) and GS% = 73 (66-81). The first generation male lacks a mucron, while the second generation male always has one. The first generation female can be recognised by the vulval lips not being raised, the possession of long double-flapped epiptygmata and the lack of a postanal swelling. Analysis of the ITS and D2D3 regions showed S. sacchari n. sp. to differ from all other Steinernema species and to belong to a new monophyletic group, the ‘Cameroonian’ clade, consisting of S. cameroonense, S. nyetense and S. sacchari n. sp. This group is closely related to the feltiae-kraussei-oregonense Clade III.

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

Nematology ◽  
2016 ◽  
Vol 18 (5) ◽  
pp. 571-590 ◽  
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.

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

Nematology ◽  
2006 ◽  
Vol 8 (2) ◽  
pp. 157-175 ◽  
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.

Steinernema riojaense n. sp., a new entomopathogenic nematode (Nematoda: Steinernematidae) from Spain

Nematology ◽  
2020 ◽  
Vol 22 (7) ◽  
pp. 825-841 ◽  
Author(s):  
Vladimír Půža ◽  
Raquel Campos-Herrera ◽  
Rubén Blanco-Pérez ◽  
Hedvika Jakubíková ◽  
Ignacio Vicente-Díez ◽  
...  
Keyword(s):  
New Species ◽  
Body Length ◽  
First Generation ◽  
Second Generation ◽  
Entomopathogenic Nematode ◽  
Phylogenetic Analyses ◽  
Infective Juvenile ◽  
Body Region ◽  
Width Ratio ◽  
Generation Female

Summary A new species of entomopathogenic nematode, Steinernema riojaense n. sp., was isolated during a survey in La Rioja province of Spain. Morphological and morphometric traits place the new species in the glaseri-group, which is characterised by having the largest infective juvenile (IJ) with an average body length in excess of 1000 μm. The IJ of S. riojaense n. sp. possess a body length of 1043 (869-1172) μm, the lateral fields are formed by eight equally spaced and developed ridges (nine incisures) in the mid-body region, giving the formula 2, 6, 8, 4, the excretory pore is located posterior to the mid-pharynx region (D% = 58), and the hyaline region occupies ca half of the tail length. The male spicules are moderately curved with a sharp tip and are golden-brown in colour with the manubrium elongate and having a length to width ratio of 1.7:1. The first-generation male tail is non-mucronate, whereas a small papilla-like mucron is developed in the second generation. There are 11 pairs of genital papillae plus a single precloacal papilla. The first-generation female possesses a moderately protruding vulva and a slightly protruding postanal swelling. The second-generation female possesses a slightly protruding vulva and a postanal swelling. The new species is further characterised by sequences of the internal transcribed spacer (ITS) and partial 28S regions (D2-D3) of the ribosomal DNA (rDNA). Phylogenetic analyses confirm that S. riojaense n. sp. belongs to the glaseri-group and forms a monophyletic subclade with other European species.

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

Nematology ◽  
2016 ◽  
Vol 18 (2) ◽  
pp. 235-255 ◽  
Author(s):  
Birhan A. Abate ◽  
Antoinette P. Malan ◽  
Louwrens R. Tiedt ◽  
Michael J. Wingfield ◽  
Bernard Slippers ◽  
...  
Keyword(s):  
South Africa ◽  
New Species ◽  
Dna Sequences ◽  
First Generation ◽  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Tail Length ◽  
Infective Juvenile ◽  
Lateral Field ◽  
Mpumalanga Province

A new species of entomopathogenic nematode, Steinernema fabii n. sp., was isolated by trapping with wax moth (Galleria mellonella) larvae from soil in an Acacia mearnsii plantation in the Mpumalanga province of South Africa. The new species is morphologically characterised by the length of the infective juvenile (IJ) of 641 (590-697) μm, by a tail length of 58 (52-64) μm, ratio a = 24 (21-41), H% = 53 (37-61) and E% = 93 (83-105). The pattern of the lateral field of the IJ of the new species is 2, 5, 2 ridges (3, 6, 3 incisures). The male of the first generation can be recognised by the long spicule of 90 (79-106) μm and gubernaculum of 66 (56-77) μm; D% = 64 (52-75) and GS% = 73 (63-86). The first generation female can be recognised by a protruding vulva with a short, double-flapped epiptygmata, and the lack of a postanal swelling, while the second generation differs in having a postanal swelling and a conical, sharply pointed tail. Analysis of DNA sequences for the ITS and D2-D3 gene regions showed S. fabii n. sp. to differ from all other Steinernema species and to belong to a new monophyletic group, the ‘Cameroonian’ clade, consisting of S. cameroonense, S. nyetense, S. sacchari and S. fabii n. sp., all from the African continent. This group is closely related to species in the feltiae-kraussei-oregonense Clade III.

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

Nematology ◽  
2011 ◽  
Vol 13 (5) ◽  
pp. 569-587 ◽  
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.

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

Nematology ◽  
2016 ◽  
Vol 18 (4) ◽  
pp. 439-453 ◽  
Author(s):  
Harun Çimen ◽  
Vladimír Půža ◽  
Jiří Nermuť ◽  
Justin Hatting ◽  
Tshima Ramakuwela ◽  
...  
Keyword(s):  
South Africa ◽  
New Species ◽  
First Generation ◽  
Entomopathogenic Nematode ◽  
Phylogenetic Analyses ◽  
Monophyletic Clade ◽  
African Species ◽  
Spicule Length ◽  
Tail Tip ◽  
A New Species

Steinernema beitlechemi n. sp. is a new species of entomopathogenic nematode isolated from soil samples collected in Bethlehem, Free State province, South Africa. The infective juveniles of S. beitlechemi n. sp. are characterised by a body length of 696 (606-768) μm, position of nerve ring of 96 (86-105) μm from the head and lateral fields with six ridges (i.e., seven lines) in mid-body. First-generation males of S. beitlechemi n. sp. can be distinguished by a spicule length of 93 (88-100) μm and 12 pairs of genital papillae. First-generation females have a moderately protruding vulva and a rounded tail tip bearing one spine-like projection. The new species is further characterised by sequences of the ITS and partial 28S regions of the ribosomal DNA. Phylogenetic analyses show S. beitlechemi n. sp. as a member of a strongly supported monophyletic clade with three other African species: S. sacchari, S. cameroonense and S. nyetense.

Steinernema ethiopiense sp. n. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Ethiopia

Nematology ◽  
2012 ◽  
Vol 14 (6) ◽  
pp. 741-757 ◽  
Author(s):  
Tewodros Tamiru ◽  
Tewodros Tamiru ◽  
Lieven Waeyenberge ◽  
Tewodros Tamiru ◽  
Lieven Waeyenberge ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Trees ◽  
First Generation ◽  
Second Generation ◽  
Dna Analysis ◽  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Its Region ◽  
Lateral Field ◽  
Tail Tip

Three isolates (Dero-1, Dero-8 and Mosisa-1) of a new entomopathogenic nematode, S. ethiopiense sp. n., were isolated by baiting soil samples from the Mendi area, Western Wollega, Ethiopia, with last instar wax moth larvae Galleria mellonella. Infective juveniles of S. ethiopiense sp. n. have a body length of 898 (768-1010) μm, a maximum of eight identical ridges (i.e., nine lines) in the lateral field, excretory pore located at mid-pharynx, hyaline layer occupying approximately half of the tail and c′ = 3.2. First generation males lack a caudal mucron, whereas second generation males possess a short spine-like mucron. The spicules are slightly arcuate, golden-brown in colour and have an ellipsoid or oblong manubrium. First generation females lack a postanal swelling and have a minute protuberance on the tail tip whereas second generation females have a postanal swelling and protruding vulva. Based on the morphology, morphometrics and DNA analysis, the new species belongs to the glaseri group. The closest relative species is the afro-tropical S. karii recorded from Kenya. The BLAST analysis of the ITS region of the rDNA revealed a similarity of 93% with S. karii, supporting the validity of S. ethiopiense sp. n. as a new species. In the phylogenetic trees the new species groups together only with S. karii (bootstrap value of 100%), but is also separated from S. karii by a bootstrap value of 100% or 70%.

scholarly journals Morphological and molecular characterisation of Steinernema hermaphroditum n. sp. (Nematoda: Steinernematidae), an entomopathogenic nematode from Indonesia, and its phylogenetic relationships with other members of the genus

Nematology ◽  
2004 ◽  
Vol 6 (3) ◽  
pp. 401-412 ◽  
Author(s):  
S. Patricia Stock ◽  
Christine T. Griffin ◽  
Rani Chaerani
Keyword(s):  
New Species ◽  
First Generation ◽  
Entomopathogenic Nematode ◽  
Phylogenetic Reconstruction ◽  
Infective Juvenile ◽  
Molecular Evidence ◽  
Lateral Field ◽  
Third Stage ◽  
28S Rdna Sequence ◽  
A New Species

Abstract Steinernema hermaphroditum n. sp., a new entomopathogenic nematode isolated from soil samples in the Moluccan islands, Indonesia, is described. Morphological observations as well as biological evidence (cross-hybridisation studies) indicate the distinctness of S. hermaphroditum n. sp. from other Steinernema spp. This new species is characterised by the presence of hermaphrodites in the first adult generation. Key morphological diagnostic characters include: a digitate tail with a mucro and a glandular spermatheca filled with sperm in the first generation hermaphrodite; the value of D%; the morphology of the male spicules and gubernaculum and the number and arrangement of the genital papillae; the values of D%, E% and the pattern of the lateral field of the third-stage infective juvenile. Additionally, molecular evidence obtained from ITS rDNA RFLP profiles, 28S rDNA sequence analyses, and phylogenetic reconstruction provide further evidence to establish this nematode as a new species.

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

2015 ◽  
Vol 90 (3) ◽  
pp. 262-278 ◽  
Author(s):  
A.P. Malan ◽  
R. Knoetze ◽  
L.R. Tiedt
Keyword(s):  
South Africa ◽  
New Species ◽  
Dna Sequences ◽  
First Generation ◽  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
The Body ◽  
Its Rdna ◽  
28S Rdna ◽  
Cross Hybridization

AbstractDuring a non-targeted survey for entomopathogenic nematodes in South Africa, a new species of Steinernema was isolated from a soil sample collected from underneath a guava tree, close to the shore at Jeffrey's Bay. The nematode was isolated by means of the insect-baiting technique using last-instar larvae of Galleria mellonella. It is described herein as Steinernema jeffreyense n. sp. The nematode can be separated from other described, closely related species in terms of the morphological and morphometric characteristics of the different life stages, and in terms of the characterization and phylogeny of DNA sequences of the internal transcribed spacer (ITS) rDNA of the 18S gene, and of the D2D3 region of the 28S rDNA gene. The new species is placed molecularly in the arenarium–glaseri–karii–longicaudatum group characterized by the following morphological characters: infective third-stage juvenile with a body length of 926 (784–1043) μm, distance from head to excretory pore of 87 (78–107) μm, tail length of 81 (50–96) μm, with an E% of 109 (86–169), and eight evenly spaced ridges (i.e. nine lines) in the middle of the body. First-generation males have a spicule length of 88 (79–95) μm and gubernaculum length of 57 (51–61) μm. Male mucron is absent in both generations. First-generation females have an asymmetrical protuberance and a short, double-flapped epiptygmata, with both flaps directed to the front. The tail of the first-generation female is shorter than the anal body width, with a mucron on the dorsal tail tip, with D% = 78 (59–99). Cross-hybridization with S. khoisanae, S. tophus and S. innovationi showed the new species to isolate reproductively from the others. The analyses of ITS rDNA and D2D3 sequence of the 18S and 28S rDNA genes support the studied nematode isolate to be a valid new species belonging to the ‘glaseri’ group (Clade V).

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