Nematodes associated with terrestrial slugs from canola fields and ornamental nurseries in South Africa

Zootaxa ◽  
2017 ◽  
Vol 4312 (1) ◽  
pp. 194 ◽  
Author(s):  
ANNIKA PIETERSE ◽  
ANTOINETTE P. MALAN ◽  
LAURA M. KRUITBOS ◽  
WILLEM SIRGEL ◽  
JENNA L. ROSS
Keyword(s):  
South Africa ◽  
Sequence Data ◽  
Large Subunit ◽  
Morphological Characteristics ◽  
Nematode Species ◽  
First Record ◽  
Small Subunit ◽  
Western Cape ◽  
Molecular Sequence Data ◽  
Molecular Sequence

A survey of nematodes that use terrestrial slugs as definitive hosts, was conducted in canola fields and ornamental nurseries located in the Western Cape province of South Africa. A total of 3290 slugs were collected from 22 different sites. On the identification of the slugs, they were vivisected and examined for internal nematodes. After identifying the nematodes found, on the basis of their morphological characteristics, their identity was confirmed using molecular sequence data for the internal transcribed spacer (ITS-1, 5.8S, ITS-2), D2-D3 expansion segments of the large subunit (LSU or 28S) and small subunit (SSU or 18S) ribosomal DNA. Of the 22 sites investigated, 13 had nematodes present, with 8 % of the slugs being found to be infected with nematodes. Seven nematode species were confirmed, including Agfa flexilis, Angiostoma margaretae, Angiostoma sp. (SA1), Caenorhabditis elegans, mermithid sp. (SA1), Phasmarhabditis sp. (SA3) and Phasmarhabditis sp. (SA4). In addition, several Angiostoma spp. were also isolated, but could only be identified to genus level due to limited material. Of the seven confirmed species, four were previously undescribed. This is the first record of A. margaretae associating with Deroceras panormitanum, Deroceras reticulatum, Lehmannia valentiana and Oopelta polypunctata. Also, this is the first time that a mermithid has been found associating with molluscs in South Africa. 

Molecular phylogeny of rhynchonellide articulate brachiopods (Brachiopoda, Rhynchonellida)

2013 ◽  
Vol 87 (2) ◽  
pp. 211-216 ◽  
Author(s):  
Bernard L. Cohen ◽  
Maria Aleksandra Bitner
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Phylogenetic Reconstruction ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Molecular Sequence Data ◽  
Molecular Sequence ◽  
Rdna Sequences ◽  
Relaxed Clock

We present here the first report based on phylogenetic analyses of small subunit (SSU/18S) and large subunit (LSU/28S) ribosomal DNA (rDNA) sequences from a wider-than-token sample of rhynchonellide articulate brachiopods, with data from 11 of ∼20 extant genera (12 species) belonging to all four extant superfamilies. Data exploration by network and saturation analyses shows that the molecular sequence data are free from major aberrations and are suitable for phylogenetic reconstruction despite the presence of large deletions in four SSU rDNA sequences. Although molecular sequence analyses cannot directly illuminate the systematics of fossils, the independent, genealogical evidence and phylogenetic inferences about extant forms that they make possible are highly relevant to paleontological systematics because they highlight the limitations of evolutionary inference from morphology. Parsimony, distance, maximum likelihood (no clock) and Bayesian (relaxed-clock) analyses all find a tree topology that disagrees strongly with the existing superfamily classification. All tested phylogenetic reconstructions agree that the taxa analyzed fall into three clades designated A1, A2, and B that reflect two major divergence events. The relaxed-clock analysis indicates that clades A and B diverged in the Paleozoic, while clades A1 and A2 reflect Permo-Triassic (and later) events. Morphological homoplasy and possible gene co-option are suggested as the main sources for the discord between the morpho-classification, the results of cladistic analyses of morphology, and the relationships reconstructed from molecular sequences. The origin, function and evolutionary implications of the deletion-bearing rhynchonellide SSU rDNA sequences are briefly discussed in relation to pseudogenes and concerted evolution in the rDNA genomic region.

Nematodes associated with terrestrial slugs in the Edmonton region of Alberta, Canada

2020 ◽  
Vol 94 ◽  
Author(s):  
T. Brophy ◽  
R.J. Mc Donnell ◽  
D.K. Howe ◽  
D.R. Denver ◽  
J.L. Ross ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Ribosomal Dna ◽  
Sequence Data ◽  
Nematode Species ◽  
Species Level ◽  
Molecular Sequence Data ◽  
Molecular Sequence ◽  
C Elegans ◽  
Facultative Parasite ◽  
Arion Rufus

Abstract A survey of nematodes associated with terrestrial slugs was conducted in residential gardens, nurseries, greenhouses and agricultural sites located in and around Edmonton, Alberta, Canada. A total of 2406 slugs were collected from 82 sites. Slugs were decapitated and cadavers were incubated for two weeks, with emerging nematodes removed and processed for identification. Nematodes were identified using molecular sequence data for the 18S ribosomal DNA. Nematodes were recovered from 20 of the 82 sites surveyed, with 24.4% of the slugs infected with nematodes. A total of seven nematodes were identified to species level, including Caenorhabditis elegans, Panagrolaimus papillosus, Pellioditis typica, Pelodera pseudoteres, Rhabditella axei, Rhabditoides inermiformis and Phasmarhabditis californica. An additional four specimens were identified to genus level, including Oscheius sp. (9), Pristionchus sp., Rhabditis sp. and Rhabditophanes sp. (1). The two most common nematode species were C. elegans and P. pseudoteres. The facultative parasite, P. californica, was recovered from a single Arion rufus specimen, collected from a seasonal nursery. To our knowledge, this study represents the first survey of slug-associated nematodes in Canada.

New taxa in Drosanthemum and a new genus in Drosanthemeae (Ruschioideae, Aizoaceae)

Phytotaxa ◽  
2020 ◽  
Vol 459 (2) ◽  
pp. 139-154
Author(s):  
CORNELIA KLAK ◽  
PAVEL HANÁČEK ◽  
ODETTE CURTIS-SCOTT ◽  
ANSO LE ROUX ◽  
PETER V. BRUYNS
Keyword(s):  
South Africa ◽  
New Species ◽  
New Genus ◽  
Sequence Data ◽  
Morphological Characteristics ◽  
Molecular Data ◽  
Western Cape ◽  
Monotypic Genus ◽  
Nomenclatural Change ◽  
A New Species

A phylogeny of all nine subgenera of Drosanthemum, based on chloroplast sequence-data, is presented. The results confirm some previously published facts, e.g. that D. zygophylloides is sister to Drosanthemum. We propose to treat this species as a new monotypic genus, Lemonanthemum, which differs from Drosanthemum in features of the leaves and fruit-stalks. In Drosanthemum s.s., the small subg. Quadrata, characterized by 4-locular fruits, is highly supported as sister to the remainder of Drosanthemum (where fruits are 5-locular). Further, our data support the transfer of Delosperma pubipetalum to Drosanthemum (where a nomenclatural change is also made). The pubescent petals, 5-locular fruits with narrow covering membranes and downward-pointing hair-like papillae on the branches suggest that D. pubipetalum is close to D. papillatum and belongs to subg. Quastea. Another species, D. badspoortense, which had been placed in D. subg. Quastea on account of its narrow covering membranes, is shown to belong to Delosperma and also lacks the unique structure of the fruit-stalk of Drosanthemum. In addition, a new species, D. overbergense, is described from disjunct patches of remnant renosterveld within the Overberg and near Albertinia, in the Western Cape of South Africa. Morphological characteristics suggest that this species belongs to subg. Xamera, but this was not corroborated by our molecular data. Finally, a new name—Drosanthemum calcareum—is proposed for the illegitimate D. intermedium and a lectotype (at BOL) is designated for D. pubipetalum. The lectotypification of D. badspoortense is also proposed.

Lost in worm space: phylogeny and morphology as road maps to nematode diversity

Nematology ◽  
2000 ◽  
Vol 2 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Paul De Ley
Keyword(s):  
Sequence Data ◽  
Nematode Species ◽  
Molecular Sequence Data ◽  
Molecular Sequence ◽  
Scientific Investigations ◽  
Taxonomic Impediment ◽  
Morphological Studies ◽  
Nematode Diversity ◽  
Specialist Knowledge ◽  
Road Maps

AbstractThe taxonomic impediment in nematology is expanding rather than receding: in the past decade estimates of nematode species richness have increased by several orders of magnitude, while the number of active nematode taxonomists has continued to decline steadily. In order to survive as a discipline in the new century, nematode taxonomy will therefore have to i) prioritise taxa that are relevant to other scientific investigations, ii) provide identification and classification tools that are easily applicable by nonspecialists, and iii) focus on revealing patterns of relatedness rather than on compiling exhaustive catalogues of species, since the latter will never remotely reach completion. Traditional morphological studies based on light microscopy do not meet these needs because they provide insufficient character resolution and require too much specialist knowledge. Phylogenetic approaches are more promising, especially when incorporating molecular sequence data as well as other non-traditional character suites. En nématologie, les obstacles taxinomiques sont en accroissement plutôt qu’en recul: pendant la dernière décennie, les estimations relative à la diversité en espèces ont été accrues par plusieurs ordre de grandeur tandis que le nombre de taxinomistes a continué à décroître régulièrement. Pour se maintenir en tant que discipline au cours du nouveau siècle, la taxinomie nématologique devra donc i) donner priorité à des taxons en relation directe avec d’autres recherches scientifiques, ii) produire des instruments d’identification et de classification plus accessibles aux non-spécialistes, et iii) se concentrer sur la découverte de relations d’affinité plutôt que sur la compilation de catalogues d’espèces lesquels n’atteindront jamais l’exhaustivité. Les études morphologiques traditionnelles basées sur la microscopie optique ne peuvent répondre à ces besoins du fait qu’elles n’ont pas une résolution suffisante pour les caractères et qu’elles requièrent trop de connaissances spécialisées. Les approches phylogénétiques sont plus prometteuses, spécialement lorsqu’elles sont basées sur des séquences moléculaires et d’autres séries de caractères non-traditionnels.

Steinernema innovationi n. sp. (Panagrolaimomorpha: Steinernematidae), a new entomopathogenic nematode species from South Africa

2014 ◽  
Vol 89 (4) ◽  
pp. 415-427 ◽  
Author(s):  
H. Çimen ◽  
M.-M. Lee ◽  
J. Hatting ◽  
S. Hazir ◽  
S.P. Stock
Keyword(s):  
South Africa ◽  
Sequence Data ◽  
Entomopathogenic Nematode ◽  
Mitochondrial Gene ◽  
Tail Length ◽  
Nematode Species ◽  
Total Body Length ◽  
Morphological Data ◽  
Cross Hybridization ◽  
Molecular Sequence Data

AbstractMorphological and molecular sequence data were combined with cross-hybridization studies and used to identify a new Steinernema sp. from Free State, South Africa. Molecular and morphological data indicate that the new species belongs to the ‘glaseri-group’ of Steinernema spp. Key morphological diagnostic characters for S. innovationi n. sp. include the morphometric features of the third-stage infective juveniles: total body length = 1054 (1000–1103) μm, tail length = 108 (97–117) μm, location of the excretory pore = 88 (82–91) μm, and D% = 58 (54–63), E% = 115 (104–137) and H% = 43 (37–46). Additionally, the morphology of the spicules and gubernaculum of the first-generation males are considered key diagnostic traits. Steinernema innovationi n. sp. was also characterized by analysis of both rDNA and mitochondrial gene sequence data, which further indicate the uniqueness of this Steinernema species.

Phasmarhabditis hermaphrodita (Nematoda: Rhabditidae), a potential biocontrol agent isolated for the first time from invasive slugs in North America

Nematology ◽  
2014 ◽  
Vol 16 (10) ◽  
pp. 1129-1138 ◽  
Author(s):  
Irma Tandingan De Ley ◽  
Rory D. McDonnell ◽  
Sandy Lopez ◽  
Timothy D. Paine ◽  
Paul De Ley
Keyword(s):  
North America ◽  
Sequence Data ◽  
Control Strategies ◽  
Large Subunit ◽  
Small Subunit ◽  
Coi Gene ◽  
Lsu Rdna ◽  
Molecular Sequence Data ◽  
First Time ◽  
Phasmarhabditis Hermaphrodita

Phasmarhabditis hermaphroditais reported for the first time in North America from cadavers of the invasive slug speciesDeroceras reticulatum,D. laeveandLehmannia valentianacollected from three different locations in California, USA. Four isolates were identified using combined morphology, morphometrics and molecular sequence data for complete internal transcribed spacer (ITS-1, 5.8S, ITS-2), D2-D3 expansion segments of the large subunit (LSU or 28S) and nearly complete small subunit (SSU or 18S) ribosomal DNA. Extremely low sequence variations in the COI gene of the mitochondria were observed among US isolates as well as between US isolates and the two UK sequences. The occurrence ofP. hermaphroditain North America has regulatory implications for potential biological control strategies against non-native gastropod species that are pests in ornamental and agricultural cultivation on this continent. The D2-D3 sequence of the LSU rDNA is new for the species.

Morphology and phylogeny of Pseudorobillarda eucalypti sp. nov., from Thailand

Phytotaxa ◽  
2014 ◽  
Vol 176 (1) ◽  
pp. 251 ◽  
Author(s):  
NARUMON TANGTHIRASUNUN ◽  
PHILIPPE SILAR ◽  
DARBHE JAYARAMA BHAT ◽  
EKACHAI CHUKEATIROTE ◽  
D.N. NALIN WIJAYAWARDENE ◽  
...  
Keyword(s):  
Rna Polymerase Ii ◽  
Ribosomal Dna ◽  
Phylogenetic Trees ◽  
Sequence Data ◽  
Large Subunit ◽  
Elongation Factor ◽  
Morphological Characteristics ◽  
Distinct Species ◽  
Small Subunit ◽  
Family Status

Pseudorobillarda is a coelomycete genus of Dothideomycetes with appendaged conidia and 15 species epithets. In this study, we isolated four strains of Pseudorobillarda from dead leaves in Thailand. DNA sequence data generated from the large subunit (28S) ribosomal DNA (nuLSU) gene was used in phylogenetic studies. The phylogenetic trees generated indicate that Pseudorobillarda form a distinct lineage in Dothideomycetes that may eventually require separate family status. The Pseudorobillarda strains comprised two distinct species and this is also supported by morphological characteristics. In this paper we introduce a new species of Pseudorobillarda, P. eucalypti and compare it with other species of the genus. We also deposit data from the internal transcribed spacer (ITS), small subunit (18S) ribosomal DNA (nuSSU),the RNA polymerase II 2nd largest subunit genes (RPB2), Translation Elongation Factor 1-α (TEF1-α) and β-Tubulin (Bt) genes from each strain in GenBank for future studies.

Morphological and molecular data supportLichina intermediaas a distinct austral-marine species in theL. pygmaeagroup

2017 ◽  
Vol 49 (4) ◽  
pp. 321-332 ◽  
Author(s):  
Matthias SCHULTZ
Keyword(s):  
Sequence Data ◽  
Morphological Characteristics ◽  
Distribution Patterns ◽  
Marine Species ◽  
Molecular Data ◽  
Separate Species ◽  
Molecular Sequence Data ◽  
Molecular Sequence ◽  
Morphological And Molecular Data

AbstractMorphological characteristics and analyses of molecular sequence data (ITS, mtSSU) indicate that the austral-marine lichenLichina pygmaeavar.intermediais distinct from the chiefly European marine speciesL. confinisandL. pygmaea. It is thus proposed to treat var.intermediaas a separate species.Lichina intermediadiffers fromL. confinischiefly in the distinctly corticated branches, and deviates fromL. pygmaeain the shorter and thinner branches. Diagnostic differences between the three species are summarized and distribution patterns discussed.

Description of Schistonchus superbus n. sp. (Nematoda: Aphelenchoididae), an associate of Ficus superba in China

Nematology ◽  
2013 ◽  
Vol 15 (7) ◽  
pp. 771-781 ◽  
Author(s):  
Yongsan Zeng ◽  
Weimin Ye ◽  
Changhui Li ◽  
Xinrong Wang ◽  
Zhijian Du ◽  
...  
Keyword(s):  
Sequence Data ◽  
Large Subunit ◽  
Nematode Species ◽  
Botanical Garden ◽  
Small Subunit ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
Academy Of Sciences ◽  
Large Subunit Rrna ◽  
Nematode Biodiversity

A new nematode species was recovered from the syconia of Ficus superba from the South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong Province, China, during a survey of nematode biodiversity from 2007 to 2012. It is described herein as Schistonchus superbus n. sp. and is characterised by possessing the combined characters of a short post-uterine sac and digitate tail without a mucron in females, excretory pore located near the metacorpus, amoeboid sperm, a unique wedge-shaped male tail with variable tip and two pairs of subventral papillae, absence of a gubernaculum and possession of sickle-shaped spicules without a cucullus and with a thorn-shaped rostrum. Schistonchus superbus n. sp. is typologically differentiated from all other described species in this genus by the possession of a wedge-shaped tail in males and a digitate tail without mucron in females. Schistonchus superbus n. sp. was easily differentiated from other sequenced species by the partial small subunit rRNA gene (SSU), D3 expansion segment of the large subunit rRNA gene (LSU) and mitochondrial DNA subunit I (mtCOI). Phylogenetic analysis with partial SSU sequences suggests that S. superbus n. sp. is sister to S. caprifici and S. hirtus, and is a polyphyletic relative to other Schistonchus species that have been sequenced. Based on inferences using LSU D3 sequence data, S. superbus n. sp. is in a well-supported monophyletic clade with S. caprifici, S. hirtus and S. macrophylla.

Sign in / Sign up

Export Citation Format

Share Document