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Diploscapteroides persicus n. sp. is described and illustrated based on morphological, morphometric and molecular data. The new species is mainly characterised by female body length of 469-673 μm, female tail length of 51-99 μm, shape of gubernaculum and spicules and arrangement of male genital papillae. Also, the arrangement of male genital papillae of the new species shows the presence of precloacal papillae, a feature that has not been previously described for the genus. The new species is comparable with all valid species of the genus, namely D. boettgeri, D. brevicauda, D. chitinolabiatus, D. coroniger, D. dacchensis and D. flexuosus, from which the morphological comparisons of the new species with aforementioned species are discussed. Phylogenetic analyses using partial sequences of SSU and LSU rRNA genes were performed for the new species, being the first representative of the genus to be phylogenetically studied using both Bayesian inference (BI) and maximum likelihood (ML) methods, and revealed that D. persicus n. sp. formed a clade with a species of Cephaloboides. [ABSTRACT FROM AUTHOR]

Two species of pinworms, Trypanoxyuris atelis and Trypanoxyuris atelophora were collected from the black-handed spider monkey ( Ateles geoffroyi ) in several localities across southeastern Mexico, representing the first record for both species in Mexican primates. Identification of pinworm species was based on morphological and molecular data. These pinworms are distinguished from other congeners, and from each other, by the buccal structure, the lateral alae, and the morphology of the oesophagus. Phylogenetic analyses based on sequences of the mitochondrial cytochrome c oxidase subunit 1 gene placed T. atelis as the sister species of Trypanoxyuris minutus, a parasite of the howler monkey Alouatta palliata , and T. atelophora as the sister species of T. microon , a parasite of the night monkey, Aotus azarae . These relationships were supported with high posterior probability values by Bayesian inference. Comparisons of additional pinworm taxa from Neotropical primates are needed to assess oxyurid diversity, and to better understand the evolutionary relationships among these nematodes and their primate hosts. [ABSTRACT FROM AUTHOR]

A new nematode species, Raphidascaris ( Raphidascaris ) macrouri n. sp. (Anisakidae), is described from male and female specimens found in the intestine, and occasionally in stomach and pyloric caeca, of two deep-water macrourid fishes (Gadiformes) off Barcelona, Mediterranean Sea: Nezumia aequalis (Günther) (type-host) and Trachyrincus scabrus (Rafinesque). Based on light and scanning electron microscopy examination, the new species shows similar morphological features as the other four valid species of the subgenus Raphidascaris Railliet & Henry, 1915, but it differs from Raphidascaris ( Raphidascaris ) acus (Bloch, 1779), Raphidascaris (Raphidascaris ) lutjani Olsen, 1952 and Raphidascaris ( Raphidascaris ) mediterraneus Lèbre & Petter, 1983 in the high number of precloacal papillae (23–32) and from Raphidascaris ( Raphidascaris ) gigi Fujita, 1928 in the length of the spicules. Moreover, Raphidascaris ( Raphidascaris ) macrouri n. sp. exhibits a high variability on the number and distribution of caudal papillae, which was not recorded in the other four mentioned species. This is the first species of this subgenus reported from the family Macrouridae. Sequences of ITS1–5.8S–ITS2 region are analysed and compared with closely related nematode species. Molecular analysis confirmed the uniformity of the R. ( R. ) macrouri n. sp. between hosts. [ABSTRACT FROM AUTHOR]

The present study deals with morphological differences between two closely related parasitic nematode species ( Anguillicola crassus Kuwahara et al., 1974 and Anguillicola novaezelandiae Moravec & Taraschewski, 1988) in two different experimentally infected eel species ( Anguilla anguilla Linnaeus, 1758 and Anguilla japonica Temminck & Schlegel, 1847). Furthermore, it considers the question whether size differences between those two species are ontogenetically determined or host species-dependent. In order to analyse these questions, experimental infections with the four possible host-parasite systems have been performed, followed by precise morphometric measurements related to body size and head structures of all resulting nematodes 120 days post infection. Body size measurements (length and width) of A. crassus generally exceeded those of A. novaezelandiae, while both Anguillicola species turned out to be smaller in Japanese eels than in European eels. Comparative measurements of neck width, maximum oesophagus width, and posterior head end width were found to be highly significant with regard to the different host-parasite systems. Shape and width of neck have been identified as reliable discriminating factors for species distinction. Generally, the relation of anterior head end width and neck width proved to be distinctly species-specific and can thus serve as a decisive and easily measureable distinguishing feature. [ABSTRACT FROM AUTHOR]

Analysis of the species composition and community structure of helminths in saiga antelope (Saiga tatarica) was performed using multi-year (1979-2013) data collected from the 'Askania Nova' Biosphere Reserve, Ukraine. During this period, 31 saiga antelopes of different ages (7 calves, 24 adults) were examined; totally, more then 63,900 helminth specimens were collected and identified by morphological criteria. Levels of saiga infection by nematodes were from 39 to 671 EPG (207±132 SD); seasonal fluctuations in saiga infections were insignificant (Mann-Whitney test; p>0.05). Nineteen helminth species were found in saigas in the 'Askania Nova': 3 species of Cestoda (Avitellina centripunctata, Moniezia expansa and Taenia hydatigena) and 16 species of Nematoda (Chabertia ovina, Haemonchus contortus, Marshallagia marshalli, Cooperia oncophora, Camelostrongylus mentulatus, Aonchotheca bovis, Skrjabinema ovis, Oesophagostomum venulosum, Trichostrongylus axei, T. colubriformis, T. probolorus, Ostertagia ostertagi, O. circumcincta, O. trifurcata, Nematodirus spp., Trichurus ovis). From 2 to 13 species per one host were observed. Nematodes dominated within the parasite community and composed more then 99 % of the total helminths found. Significant differences were found in helminth diversity between young and adult saigas (p<0.05). Prevalence- frequency distribution revealed multimodal structure of helminth community with dominant, subdominant, background and rare species. The highest number of helminthes (14 species and 50 % of the total amount) inhabited the small intestine; 11 species (45 %) were found in the abomasum and 9 species (5 %) in the large intestine. The Bray-Curtis cluster analysis revealed significant differences within the helminth communities in saigas from the 'Askania Nova' Biosphere Reserve and saigas from Kazakhstan, Dagestan and Kalmykia. [ABSTRACT FROM AUTHOR]

Paratylenchus (Gracilacus) straeleni (De Coninck, 1931) Oostenbrink, 1960 was detected for the first time in Turkey. Our studied population was found in the rhizosphere soil of hazelnut orchards in Ordu. Females and males were studied morphologically and morphometrically by light microscopy and molecularly by sequencing the D2-D3 of the 28S rDNA gene. We present here the morphological and molecular characterisation, phylogenetic analysis of examined population and comparison of variability of worldwide known populations of P. straeleni. [ABSTRACT FROM AUTHOR]

The distribution of Pratylenchus species associated with wheat crops was investigated in Bohemian region of the Czech Republic. In total twelve localities were sampled. The populations were identified based on morphology and morphometrics, and further characterised based on sequences of the rDNA D2/D3 region and 18S gene. Pratylenchus crenatus was present in two localities and P. neglectus in five localities. At one locality both species were detected. Sequence analysis of 18S and D2/D3 region of three populations of P. crenatus reveal no variation while five populations of P. neglectus differ by 0 to 0.14 % (18S) and 0.17 to 0.50 % (D2/D3). [ABSTRACT FROM AUTHOR]

Three species of the family Tylenchidae, including one new and two known species, are described and illustrated. Atetylenchus minor n. sp. is characterised by its short body length of 633 (558-691) µm, MB = 45 (41-46), lateral field with four crenate incisures, stylet 12.0 (11.5-12.5) µm long, without distinct basal knobs but with swollen arms of the shaft at its base, V = 56.3 (53.7-59.3), absence of lateral vulval membranes, and conical tail 57 (51-62) µm long with a rounded tip. Morphological differences of the new species with four known species of the genus, namely A. abulbosus, A. graminus, A. amiri and A. metaporus, are discussed. Molecular phylogenetic studies of the new species using 1089 bp partial sequences of 18S rDNA revealed that the new species formed a clade with an unpublished species assigned to Psilenchus in Bayesian inference (BI) with low Bayesian posterior probability (BPP). This clade forms a sister clade to a major clade containing two species of Psilenchus and several belonolaim species and genera. The same result was achieved using maximum likelihood (ML) analysis. Morphological and molecular phylogenetic studies were also performed on two other species, Malenchus labiatus and Neothada cancellata, using 28S rDNA D2-D3 sequences. In the inferred Bayesian tree, M. labiatus formed a clade with other species of Malenchus with 28S information with maximal support (1.00 BPP), while N. cancellata formed a clade with Boleodorinae, again with maximal (1.00) BPP. [ABSTRACT FROM AUTHOR]

Two commensal associates of bees, Allodiplogaster josephi n. sp. from the Dufour's gland of a cellophane bee (Colletes thoracicus) from Maryland, USA, and A. seani n. sp. from the abdominal glands of an andrenid bee (Andrena alleghaniensis) from New York, USA, are described and illustrated. Both species were collected as dauers from their respective hosts and cultured on bacteria on tryptic soy broth (TSB) or NGM agar. Allodiplogaster josephi n. sp. and A. seani n. sp. are morphologically closer to each other than to other species of Allodiplogaster, which was recently revised to include 37 valid species. However, the two new species are distinguished by reproductive isolation, shape of the spicule manubrium, host associations and molecular characters, the latter in sequences of the near-full length small subunit (SSU) rRNA gene, D2-D3 expansion segments of the large subunit (LSU) rRNA gene and partial mitochondrial COI. Morphological characterisation was supplemented by scanning electron microscopy (SEM), which revealed furcation of both v5 and v6 male genital papillae, consistent with previous reports for species of the henrichae group of Allodiplogaster. [ABSTRACT FROM AUTHOR]

The woodwasp, Sirex nigricornis (Hymenoptera: Siricidae), is solitary and utilizes a symbiotic fungus to extract nourishment from pine trees to feed its larvae. The woodwasp has a brief adult life, but the larvae develop for 1–3 years in the tree xylem. Infections with the nematode Deladenus proximus have been documented in the native woodwasp, S. nigricornis in the eastern United States and Canada. These nematodes appear to sterilize female woodwasps; however, the extent of the pathology and other aspects of the biology of D. proximus remain unknown. In this study we examined the effects of D. proximus on S. nigricornis using fresh – not preserved – specimens. Between 2009 and 2012, a total of 1639 woodwasps were examined for internal nematodes from emerging sites in Illinois, Louisiana and South Carolina. From this total, only 112 individuals were infected with the nematode D. proximus , with varying prevalence across localities and years. Nematodes were found inside every egg of infected females, as well as the hemocoel and the mycangia. Morphometric analyses of mycetophagous reared adult nematodes suggest that a single species is present in localities from Arkansas, Illinois, Louisiana, New York and South Carolina. The screening of the mitochondrial cytochrome oxidase subunit 1 ( cox1 ) of these organisms is consistent with this pattern in that all of these individuals belong to a single clade. Deladenus proximus appears to be an efficient sterilizer, yet its prevalence is relatively low. Experimental infections of the invasive Sirex noctilio are recommended to test the viability of using this nematode as a biological control agent. [ABSTRACT FROM AUTHOR]

During a survey of nematode associates of ambrosia beetles from dead and dying red bay and avocado trees affected by the laurel wilt epidemic in southern Florida, a Ruehmaphelenchus species was isolated from the non-native ambrosia beetle, Xylosandrus crassiusculus. The new species is characterised by its possession of an oral disc at the stoma opening, three lines in the lateral field, male spicule with clear dorsal and ventral limbs connected by elongated triangular cuticle, thin membrane-like tissue and cuticular bridge-like structure, conical tail with pointed tip of males and conical tail with digitate mucro of females. The new species is very similar to four previously described species: R. asiaticus, R. digitulus, R. thailandae and R. sirisus, and can be distinguished only by some minor morphological differences in male tail characters, i.e., spicule morphology, position of genital papillae and tail tip shape, and morphometric values. However, the new species is phylogenetically unique, i.e., it is the basal taxon of the Ruehmaphelenchus clade and close to Bursaphelenchus spp. Ruehmaphelenchus juliae n. sp. is therefore proposed based on its morphological diagnostic characters and molecular sequences of near-full-length of SSU, internal transcribed spacer region, D1, D2 and D3 expansion segments of LSU ribosomal RNA and partial mitochondrial COI genes. [ABSTRACT FROM AUTHOR]

A new bisexual species of Rotylenchus from North-western Iran is described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus urmiaensis n. sp. is characterised by having a truncate lip region with irregular longitudinal striation, lateral field areolated only in pharynx region, stylet length 34-40 µm, vulva positioned at 53-61%, and female tail conoid-rounded to dorsally convex-conoid with 5-10 annuli. Rotylenchus urmiaensis n. sp. appears to be similar to R. striaticeps, from which it may be differentiated morphologically by a slightly shorter body length (870-1269 vs 1000-1723 µm), shorter stylet (34-40 vs 39-50 µm), female tail shape (conoid-rounded to dorsally convex-conoid vs rounded), frequency of males (rare vs common as abundant as females), shorter spicules (39-43 vs 41-50 µm) and phasmid position (varying from three annuli anterior or three annuli posterior to anus vs at level to seven annuli anterior to anus), and molecularly. The results of phylogenetic analyses based on sequences of D2-D3 expansion region of 28S, ITS-rDNA, 18S rDNA, and the partial cytochrome c oxidase subunit 1 (coxI) mtDNA, confirmed the species differentiation and the close molecular relationship between R. urmiaensis n. sp. and R. striaticeps. [ABSTRACT FROM AUTHOR]

During a survey of entomopathogenic nematodes in North Carolina, USA, a Pristionchus species was recovered using the Galleria bait method. Morphological studies with light microscopy and scanning electron microscopy, mating tests with reference strains, as well as molecular analyses of the near-full-length small subunit rRNA gene (18S) and D2-D3 expansion segments of the large subunit rRNA gene (28S) identified this isolate as Pristionchus aerivorus. Exposed Galleria larvae were killed within 48 h and high numbers of nematodes were recovered from the cadavers about 5 days later. Preliminary tests revealed that this nematode is capable of infecting at least two other insect species (Helicoverpa zea and Tenebrio molitor) under laboratory conditions. The status of the genus Chroniodiplogaster is discussed and confirmed as a junior synonym of Pristionchus based on morphological observation and molecular phylogenetic analysis. [ABSTRACT FROM AUTHOR]

Background: During the fourth larval (L4) stage, vulval cells of C. elegans undergo extensive morphogenesis accompanied by changes in gene expression. This phase of vulval development, occurring after the well-studied induction of vulval cells, is not well understood but is potentially a useful context in which to study how a complex temporal sequence of events is regulated during development. However, a system for precisely describing different phases of vulval development in the L4 stage has been lacking. Results: We defined ten sub-stages of L4 based on morphological criteria as observed using Nomarski microscopy (L4.0 ~ L4.9). Precise timing of each sub-stage at 20 °C was determined. We also re-examined the timing of expression for several gene expression markers, and correlated the sub-stages with the timing of other developmental events in the vulva and the uterus. Conclusions: This scheme allows the developmental timing of an L4 individual to be determined at approximately one-hour resolution without the need to resort to time course experiments. These well-defined developmental stages will enable more precise description of gene expression and other developmental events. [ABSTRACT FROM AUTHOR]

Parasitic nematodes of the family Mermithidae were found to be infecting the introduced European earwig Forficula auricularia (Dermaptera: Forficulidae) in Dunedin, South Island, New Zealand. Adult females were later collected from various garden plants while depositing eggs. These mermithid specimens were identified morphologically as Mermis nigrescens Dujardin, 1842. A genetic distance of 0.7% between these specimens and a M. nigrescens isolate from Canada (18S rRNA gene), suggests that they have diverged genetically, but there are currently no available comparable sequences for the European M. nigrescens. Two additional nuclear fragments were also amplified, the 28S rRNA and the ribosomal DNA first internal transcribed spacer (ITS1), providing a basis for future studies. Bearing in mind the morphological similarity with other reported M. nigrescens and the lack of sequence data from other parts of the world, we retain the name M.nigrescens, and suggest that the species may be found to represent a complex of cryptic species when more worldwide data are available. Herein, we present a brief description of the post-parasitic worms and adult females, along with an inferred phylogeny using 18S rRNA gene sequences. [ABSTRACT FROM AUTHOR]

Current trait-based indices of soil fauna for assessing soil quality rely on extensive knowledge of life history traits for hyper-diverse groups. We look at the effects of clear-cut forest harvesting and subsequent wood ash application on the free-living nematode community using trait-based indices and body size spectra. We test the hypothesis that body size is a unifying trait and that the body size spectra can be used to demonstrate changes in soil quality while overcoming taxonomic impediments. Undisturbed boreal forest floor soils were compared with clear-cut sites amended with zero, one-half calcium equivalent wood ash, equivalent calcium reintroduction, and twice calcium reintroduction. Total abundance, trait-based metrics for the Maturity Index, and two metrics of body size spectra were calculated. Nematode abundance was not a good indicator of soil disturbance, while traditional trait-based approaches (the summed Maturity Index) demonstrated predicted changes in community structure. Analysis of two types of body size spectra elucidated how the community had changed under disturbance, and revealed that smaller bodied organisms were lost under ash amended treatments compared to both clear-cut and undisturbed forest. Using the body size spectra for nematodes is a simple addition to current trait-based approaches that can supplement soil assessments for disturbance and quality without requiring taxonomic expertise. [ABSTRACT FROM AUTHOR]

Behavioural innovation and morphological adaptation are intrinsically linked but their relationship is often poorly understood. In nematodes, a huge diversity of feeding morphologies and behaviours can be observed to meet their distinctive dietary and environmental demands. Pristionchus and their relatives show varied feeding activities, both consuming bacteria and also predating other nematodes. In addition, Pristionchus nematodes display dimorphic mouth structures triggered by an irreversible developmental switch, which generates a narrower mouthed form with a single tooth and a wider mouthed form with an additional tooth. However, little is known about the specific predatory adaptations of these mouth forms or the associated mechanisms and behaviours. Through a mechanistic analysis of predation behaviours, in particular in the model organism Pristionchus pacificus, we reveal multifaceted feeding modes characterised by dynamic rhythmic switching and tooth stimulation. This complex feeding mode switch is regulated by the neurotransmitter serotonin in a previously uncharacterised role, a process that appears conserved across several predatory nematode species. Furthermore, we investigated the effects of starvation, prey size and prey preference on P. pacificus predatory feeding kinetics, revealing predation to be a fundamental component of the P. pacificus feeding repertoire, thus providing an additional rich source of nutrition in addition to bacteria. Finally, we found that mouth form morphology also has a striking impact on predation, suppressing predatory behaviour in the narrow mouthed form. Our results therefore hint at the regulatory networks involved in controlling predatory feeding and underscore P. pacificus as a model for understanding the evolution of complex behaviours. [ABSTRACT FROM AUTHOR]

Morphological descriptions of two Halomonhystera species (Nematoda, Monhysterida) are presented ( Halomonhystera hermesi and Halomonhystera socialis). Halomonhystera hermesi sp. n. occurs in a dense monospecific and homogeneous population on bacterial mats in the Håkon Mosby mud volcano in the Barents Sea at a depth of 1,280 m. The species is an endemic lineage distinctly separated from other shallow-water cryptotaxa of the Halomonhystera disjucta species complex on the base of the mitochondrial gene cytochrome oxidase subunit I (genetic divergence 19.6-23.8 %) and nuclear genetic markers, and on the base of morphometrics by Van Campenhout et al. (). H. socialis (Bütschli ) is redescribed on the basis of White Sea specimens. This species dwells in mass on the detached kelp accumulation in the upper sublittoral. H. socialis is differentiated from other species of the Halomonhystera disjuncta complex morphometrically by a larger body size and by genetic divergence in nuclear markers. The genus Halomonhystera Andrássy is redefined, and its morphospecies list is reviewed. Species H. bathislandica (Riemann ) comb. n., H. fisheri (Zekely et al. ) comb. n., H. islandica (De Coninck ) comb. n. and H. vandoverae (Zekely et al. ) comb. n. are transferred to Halomonhystera from Thalassomonhystera; H. paradisjuncta (de Coninck ) comb. n., H. rotundicapitata (Filipjev ) comb. n. and H. taurica (Tsalolikhin ) comb. n. transferred to Halomonhystera from Geomonhystera. Halomonhystera ambiguoides (Bütschli ) is considered as species inquirenda because of incompleteness of its diagnosis. [ABSTRACT FROM AUTHOR]

Additional information on Rhigonema brevicollum, the type of the genus Rhigonema, and on Heth juli, the type of the genus Heth, is presented based on original, hitherto unpublished, descriptions held in the Cobb Archive at the USDA, Beltsville, MD, USA. Both species were originally published as small annotated illustrations in a general work, although the promised full descriptions were never published by Cobb. The genus Rhigonema is shown to be based on a species lacking a vaginal diverticulum in the female genital system, but having a long, Type 2, ovejector. The genus Dudekemia, originally differentiated from Rhigonema on an assumed (and erroneous) difference in female genital tract form, is confirmed as a junior synonym of Rhigonema. A full description of both sexes of Heth juli is also provided, again based on Cobb's original notes, thereby defining the type species with greater precision than was previously possible. [ABSTRACT FROM AUTHOR]

Toxascaris leonina (Linstow, 1902) is a most common intestinal parasite of various animals in Felidae and Canidae. In the present paper, light and scanning electron microscopy (SEM) were used to study the morphological aspects of adult worms of this nematode in detail, based on the material collected from Panthera leo (Linnaeus) and Felis lynx (Linnaeus) (Carnivora: Felidae) in China. The results showed that there were some morphometric differences between the present material and the previous studies, including the body size, the width and length of cervical alae, the number of denticles on each lip and the tail length of the female. Previously unreported morphological features were also revealed. These supplementary morphological and morphometric data contributed to a more accurate identification of this worldwide distributed ascarid nematode. [ABSTRACT FROM AUTHOR]

The article discusses development of oral structure in cystidicolid nematode Salmonema emphemeridarum. Topics discussed include identification of third stage larva to genus and species; collection of adult female worms from brook trout Salvelinus fontinalis and role of development of reproductive structures in somatic development of the worm.

Xiphinema herakliense n. sp. from wild olive and cultivated trees in Vathy Rema and other localities, Heraklion province of Crete, Greece, is described based on morphological and molecular characters. The new species is characterised by having differentiation in the tubular part of the uterus, body length 4.1 (3.3-5.5) mm, odontostyle 149 (135-163) pm long, odontophore 85 (71-98) pm long, female tail dorsally convex-conoid with subdigitate peg, and presence of functional males. The polytomous identification code of the new species is: A4, B2 + 3, C5a, D6(5), E5, F4(5), G3, H2, I3, J5, K5, L2. The new species belongs to morphospecies Xiphinema nonamericanum Group 5 characterised by having two equally developed female genital branches with uterine differentiation, presence of pseudo-Z-organ with small granular bodies plus small spines (in low number) and crystalloid bodies along uterus, and a short, rounded tail ending in a peg. Xiphinema herakliense n. sp. appears closely related to X. barense, X. horvatovicae, X. lanceolatum, X. loteni, X. sphaerocephalum and X. thorneanum, from which it may be differentiated morphologically and/or molecularly. The results of the phylogenetic analyses based on the sequences of the D2-D3 expansion regions of the 28S rRNA gene and ITS1 rRNA genes are also supportive of its specific status. [ABSTRACT FROM AUTHOR]

Two Sheraphelenchus populations were isolated from pine wood packaging from Italy and onion bulbs from South Korea at Ningbo Port, China, respectively. The former, on the basis of morphology and molecular sequencing, is described as S. parabrevigulonis n. sp., which is characterised by a stylet length of 11 µm, three lines in the lateral field, excretory pore at level with, or slightly posterior to, nerve ring, V = 93.1, and spicules with long condylus and membrane-like rostrum in a shallow triangular shape. The species from onion, also on the basis of morphology and sequence data, was identified as S. sucus, which is characterised by a stylet length of 13 µm (erroneously stated to be ca 6 µm in the type description), excretory pore at level of, or posterior to, median bulb, and V = 80.9. The phylogeny trees based on rDNA 18S, 28S D2-D3 and ITS1/2 sequences revealed that S. parabrevigulonis n. sp. and S. sucus clustered into a clear clade and grouped with Bursaphelenchus species. The study enriched the taxonomic information of Sheraphelenchus and confirmed its status as an independent genus. [ABSTRACT FROM AUTHOR]

Ektaphelenchoides caspiensis n. sp. is described and illustrated based on morphological, morphometric and molecular characters. The new species is characterised by its continuous lip region, obscure lateral field, females with body length of 499-572 µm, 9-10 µm long stylet, excretory pore posterior to base of metacorpus at 62-72 µm from anterior body end, short post-uterine sac ca 0.5 times corresponding body diam. or 4-9 µm long, and posterior body end (i.e., including 'tail') very long and filiform. Males are common and have 7-8 µm long spicules, five copulatory papillae and a long (109-140 µm) conoid tail with very long filiform terminus. Based on morphological and molecular characters, it comes close to five known species of the genus, namely: E. attenuata, E. fuchsi, E. kelardashtensis, E. musae and E. ruehmi. It differs from the closest species, E. kelardashtensis, by the shorter female stylet (9-10 vs 13-16 µm), more anterior vulva (V = 51.7-58.1 vs 61.5-68.0), more posterior excretory pore (62-72 vs 55-66 µm from anterior end), very long posterior body (i.e., including 'tail') in female, and male tail shape (conoid with very long filiform terminus vs conoid, sharply pointed). Comparisons with other close species of the genus are also discussed. Molecular analyses were performed using 732 bp of the partial ribosomal RNA large subunit gene (D2-D3 of LSU) using Bayesian inference (BI) and maximum likelihood (ML) methods and showed that the new species formed a clade with one species of the genus (E. fuchsi) and Devibursaphelenchus lini. [ABSTRACT FROM AUTHOR]

The identity and evolutionary relationships of the genus Rhyssocolpus are analysed and discussed using an integrative approach including morphological data and partial SSU-rDNA sequences. An Iberian population of R. iuventutis is characterised in detail, providing the first SEM observations of the genus. New sequences of the genera Enchodelus and Rhyssocolpus are provided for comparative purposes. Both morphological and molecular evidence support a separate status for the aforementioned two genera and Heterodorus, of which the latter and Rhyssocolpus shared a recent common ancestor, whereas Enchodelus did not, as had been traditionally assumed, occupy a close position. The Nordiidae is confirmed to be an artificial taxon. The taxonomy of Rhyssocolpus is revised and an emended diagnosis, updated list of species, key to their identification and compendium of their morphometrics are provided. Some nomenclatorial changes are also proposed: R. alleni and R. paradoxus are retained under Eudorylaimus, their original genus, whereas R. brasiliensis is transferred to Eudorylaimus as E. brasiliensis (Meyl, 1956) comb. n. [ABSTRACT FROM AUTHOR]

Two populations of Xiphinema ingens were recovered and characterised based on morphological, morphometric and molecular data. Interesting morphological variation was observed on the nature of differentiation in uterus of females between both populations, i.e. one population had only a pseudo-Z-organ in the shape of globular bodies, whilst the second population had a similar pseudo-z-organ but also had crystalloids which varied in size and number and were located near the pseudo-z-globules or sometimes at some distance from them towards the vagina. Variation was also observed in the shape of tail of juveniles within each population as well as between two recovered populations. Both populations had the same range of morphometric data and formed a fully supported clade in both Bayesian inference (BI) and maximum likelihood (ML) methods of phylogenetic analyses using partial sequences of 28S rDNA D2-D3 and ITS1 regions. The two populations of X. ingens formed a clade with another Xiphinema species native to Iran (X. castilloi) in 28S and two species, X. macroacanthum and X. bernardi, in ITS1 trees. [ABSTRACT FROM AUTHOR]

We studied the Caenorhabditis elegans anal depressor development in larval males and hermaphrodites to address how a differentiated cell sex-specifically changes its morphology prior to adulthood. In both sexes, the larval anal depressor muscle is used for defecation behavior. However in the adult males, the muscle’s sarcomere is reorganized to facilitate copulation. To address when the changes occur in the anal depressor, we used YFP:actin to monitor, and mutant analysis, laser-ablation and transgenic feminization to perturb the cell’s morphological dynamics. In L1 and L2 stage larva, the muscle of both sexes has similar sarcomere morphology, but the hermaphrodite sex-determination system promotes more growth. The male anal depressor begins to change in the L3 stage, first by retracting its muscle arm from the neurons of the defecation circuit. Then the muscle’s ventral region develops a slit that demarcates an anterior and posterior domain. This demarcation is not dependent on the anal depressor’s intrinsic genetic sex, but is influenced by extrinsic interactions with the developing male sex muscles. However, subsequent changes are dependent on the cell’s sex. In the L4 stage, the anterior domain first disassembles the dorsal-ventral sarcomere region and develops filopodia that elongates anteriorly towards the spicule muscles. Later, the posterior domain dissembles the remnants of its sarcomere, but still retains a vestigial attachment to the ventral body wall. Finally, the anterior domain attaches to the sex muscles, and then reassembles an anterior–posteriorly oriented sarcomere. Our work identifies key steps in the dimorphic re-sculpting of the anal depressor that are regulated by genetic sex and by cell–cell signaling. [ABSTRACT FROM AUTHOR]

Morphological and molecular diversity among populations of cereal cyst nematodes (CCN) from wheat production areas in Ismailia province, Egypt, was investigated using light microscopy, ITS-RFLP and sequencing of the rDNA-ITS. CCN were found in five out of seven regions in Ismailia, the highest incidence being found in El Shark (West Sinai). The Egyptian populations were identified as H. averne according to morphometries of cyst vulval cone and second-stage juveniles. No differences in ITS-RFLP patterns generated by 17 restriction enzymes were detected among the Egyptian populations although the Egyptian populations could be distinguished from German populations of H. avenae and H. filipjevi. The analyses of ITS region sequences confirmed the species identification of the Egyptian populations as they clustered with H. avenae populations from Iran, Saudi Arabia, India, Israel and China. [ABSTRACT FROM AUTHOR]

A new monosexual species of Rotylenchus is described and illustrated based on morphological, morphometric and molecular studies from northern Iran. Rotylenchus dalikhaniensis n. sp. is characterised by having a continuous, conoid lip region with four, rarely three, annuii, lateral fields regularly areolated in pharyngeal region and irregularly throughout the body except in tail region, rarely with anastomoses at mid-body, body without longitudinal striations, stylet 34-36 //in long, vulva located at 59-64%, tail with 16-19 annuii and ventral projection, and having no males in population. The differences of the new species with five known species, namely R. breviglans, R. alii, R. pakistanensis, R. echelimae and R. provincialis, are discussed. Phylogenetic analyses using 681 bp partial sequences of D2-D3 expansion region of the 28S and 383 bp ITS 1-rRNA genes revealed that the new species formed a clade with some species of Helicotylenchus and Rotylenchus, respectively. [ABSTRACT FROM AUTHOR]

Morphological identification of spiral nematodes of the genus Helicotylenchus is a difficult task because most characters used for their diagnosis vary within species. In this paper we provide morphological and molecular characterisations of several spiral nematodes, II. broadbalkiensis, H. digonicus, H. dihystera, H. microlobus, H. paxilli and H. pseudorobustus, collected in different geographical areas of USA, Switzerland, Italy, New Zealand, Spain, UK, South Korea and Russia. We suggest that H. microlobus and H. pseudorobustus are valid species separated from each other morphologically and molecularly. Seven species with distinct molecular characteristics are also distinguished, but are not ascribed morphologically to any specific taxon because of the low number of specimens available. Phylogenetic relationships of H. pseudorobustus with other Helicotylenchus species are given as inferred from the analyses of 154 sequences of the D2-D3 of 28S rRNA gene and 37 sequences of ITS rRNA gene. [ABSTRACT FROM AUTHOR]

Several seamounts are known as ‘oases’ of high abundances and biomass and hotspots of biodiversity in contrast to the surrounding deep-sea environments. Recent studies have indicated that each single seamount can exhibit a high intricate habitat turnover. Information on alpha and beta diversity of single seamount is needed in order to fully understand seamounts contribution to regional and global biodiversity. However, while most of the seamount research has been focused on summits, studies considering the whole seamount structure are still rather poor. In the present study we analysed abundance, biomass and diversity of nematodes collected in distinct physiographic sites and surrounding sediments of the Condor Seamount (Azores, North-East Atlantic Ocean). Our study revealed higher nematode biomass in the seamount bases and values 10 times higher in the Condor sediments than in the far-field site. Although biodiversity indices did not showed significant differences comparing seamount sites and far-field sites, significant differences were observed in term of nematode composition. The Condor summit harboured a completely different nematode community when compared to the other seamount sites, with a high number of exclusive species and important differences in term of nematode trophic diversity. The oceanographic conditions observed around the Condor Seamount and the associated sediment mixing, together with the high quality of food resources available in seamount base could explain the observed patterns. Our results support the hypothesis that seamounts maintain high biodiversity through heightened beta diversity and showed that not only summits but also seamount bases can support rich benthic community in terms of standing stocks and diversity. Furthermore functional diversity of nematodes strongly depends on environmental conditions link to the local setting and seamount structure. This finding should be considered in future studies on seamounts, especially in view of the potential impacts due to current and future anthropogenic threats. [ABSTRACT FROM AUTHOR]

The morphology of dorylaimid spicules is richer than usually conceived and shows interesting interspecific variations that have not received much attention. New ideas are proposed to describe these structures, including a delimitation or definition of their parts and a series of morphometries, either (absolute) measurements or ratios. Three descriptive examples are presented. Several morphological characters (head shape, development of the ventral hump, etc.) and a number of morphometric features (total and relative lengths, relative size of the median piece, terminal tip width, etc.) are especially useful for species characterisation and comparative purposes. [ABSTRACT FROM AUTHOR]

A population of Xiphinema barense from wild olive trees in Torre Pozzella, Brindisi province, southern Italy, is described using both morphological and molecular studies and compared with the description of the type specimens. The wild olive nematode population agrees very well with all morphometries provided in the original description. However, detailed observations of the lumen of the tubular portion of the uterus in paratypes and specimens of the new population revealed a clear pseudo-Z-organ with small granules mixed with crystalloid bodies which were previously undetected. Photomicrographs of adult paratypes, which were lacking in the original description, and of specimens of the new population from wild olive trees are provided. The results of the phylogenetic analyses based on the sequences of the D2-D3 expansion regions of the 28S rRNA gene and ITS rRNA genes confirm the species differentiation and indicate the phylogenetic position of X. barense and its relationship with closely related species. [ABSTRACT FROM AUTHOR]

Devibursaphelenchus kheirii sp. n. is described and illustrated based on morphological, morphometric and molecular data. The new species is characterised by females with 370-472 pm body length, lip region separated from the body by a shallow constriction, three lines in lateral field, stylet short, 13.5-15.0 pm long, lacking basal knobs or swellings, excretory pore posterior to metacorpus, vulval flap absent, post-uterine sac short, without sperm, rectum and anus obscure, posterior end of the body elongate-conoid with finely rounded terminus. Males of the new species are characterised by their tail ventrally curved after fixation, having two pairs of caudal papillae, spicules 9-11 pm long with an elongated condylus, with rounded tip, pointed rostrum, lacking cucullus and having small conical terminal bursa. The new species comes close to D. hunanensis, D. lini and D. wangi. Beside morphological comparisons, the molecular phylogenetic analyses based on 778 bp of partial sequences of 28S rDNA D2-D3 were performed using two Bayesian inference (BI) and maximum likelihood (ML) methods and revealed that D. kheirii sp. n. formed a clade with the remaining species of the genus and one species of Ektaphelenchoides. This is the first report on occurrence of the genus Devibursaphelenchus in Iran. Devibursaphelenchus eproctatus syn. n. is proposed as a junior synonym of D. hunanensis. [ABSTRACT FROM AUTHOR]

Sectonema ventrale, the type species of the genus, is redescribed on the basis of type material as well as other specimens originally examined by Thorne. Description, morphometries and LM pictures are provided. An updated diagnosis is given and the identity of several (other than type) populations is discussed. It is characterised by its 7.09-10.42 mm long body, lip region offset by deep constriction and 25-27 μm broad, mural tooth 12-14 μm long ventrally, pharyngeal expansion occupying 68-73% of total neck length, uterus 2.5-4.2 times the corresponding body diam., pars refringens vaginae well developed, V = 48-56, female tail rounded conoid (47-71 μm, c = 117-174, c' = 0.7-0.8), spicules 120 μm long, and eight or nine irregularly spaced ventromedian supplements with a hiatus. The nature of the stomatal protrusihle structure is analysed and discussed, concluding that it is more a reduced odontostyle than a typical mural tooth, a point that should be the subject of further studies. [ABSTRACT FROM AUTHOR]

Surveys conducted in peanut production areas of China revealed peanut pod rot in several fields in Shandong and Hebei Provinces, China. A large quantity of an unknown stem nematode was isolated from the hulls and seeds of peanuts, herein described as Ditylenchus arachis n. sp. The new species is characterized by a combination of the following features: lateral lip sectors distinctly projected, stylet delicate, 8·4-10 µm in length, six lines in the lateral field, tail elongate-conoid, bursa covering about 68-86% of tail length. Pathogenicity tests showed that D. arachis n. sp. could infect peanut (Arachis hypogaea), but not sweet potato (Ipomoea batatas) or potato (Solanum tuberosum). Morphologically, D. arachis n. sp. appears closest to D. africanus, D. myceliophagus and D. destructor, but can be differentiated based upon a combination of morphological characteristics, host preference and molecular sequence data. The results of the phylogenetic analysis, based on 18S rDNA, the D2-D3 expansion region of 28S rDNA, and the ITS1-5·8S-ITS2 region, confirmed its status as a new species. A sister relationship with D. destructor was appointed, rather than with its ecologically very similar congener D. africanus. [ABSTRACT FROM AUTHOR]

During routine survey for amphibian nematodes from coalfield areas of West Bengal, India 7 male and 12 female nematodes were recovered from the rectum of one out of three Duttaphrynus melanostictus (Schneider, 1899) examined for helminth infection from Kulti, Burdwan. On examination the recovered nematodes were found to belong to a new species of the genus Aplectana (Nematoda: Cosmocercidae) and the name Aplectana duttaphryni sp. nov. is proposed for them. This species is most similar to those species which possess gubernaculum but differs from all by distribution pattern of caudal papillae. Aplectana duttaphryni sp. nov. represents 49 species assigned to the genus, but only the 4 species reported from Oriental realm and second from India. [ABSTRACT FROM AUTHOR]

Two new nematode species, Bakeria schadi sp. nov. and Falcaustra malaysiaia sp. nov. from the gastrointestinal tract of McGuire's rock gecko, Cnemaspis mcguirei (Sauria: Gekkonidae) collected in Peninsular Malaysia are described. The two species now assigned to Bakeria are separated on the bases of male bursa type and location of the excretory pore: type II in B. schadi sp. nov. and type I in B. bakeri; location of excretory pore, anterior to nerve ring in B. schadi sp. nov. and posterior to nerve ring in B. bakeri. Falcaustra malaysiaia sp. nov. is most similar to F. chabaudi, F. concinnae, F. condorcanquii, F. barbi, F. dubia, and F. tchadi in that these 7 species possess 1 pseudosucker, 1 median papilla plus 10 pairs caudal papillae, and spicules with lengths between 1 and 2 mm. F. barbi and F. tchadi lack adcloacal papillae; the remaining 5 species possess 1 pair of adcloacal papillae. Falcaustra chabaudi is known from Nearctic salamanders; F. concinnae from Nearctic turtles; F. condorcanquii from Neotropical frogs, F. dubia from Oriental frogs, and F. malaysiaia sp. nov. from Oriental geckos. Two additional species of Nematoda were found, Cosmocerca ornata and Meteterakis singaporensis. Cnemaspis mcguirei represents a new host record for Cosmocerca ornata and Meteterakis singaporensis. [ABSTRACT FROM AUTHOR]

Cucullanus hainanensis sp. nov., collected from Muraenichthys gymnopterus (Bleeker) (Anguilliformes: Ophichthidae) in the South China Sea, was described using both light and scanning electron microscopy. The new species can be readily distinguished from its congeners by the large pseudobuccal capsule, the position of excretory pore and deirids, the length of spicules (0.64-0.76 mm, 5.84-6.67% of body length) and gubernaculum (0.21-0.24 mm), the number and arrangement of caudal papillae and the particular morphology of cloacal region in male. The new species was also characterized using molecular methods by sequencing and analysing the small subunit (18S) and the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA). In addition, Cucullanus muraenesocis (Yin et Zhang, 1983) was regarded a homonym of C. muraenesocis Yamaguti, 1961, and a new name, Cucullanus wangi nom. nov. was given to it. [ABSTRACT FROM AUTHOR]

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) /xm, distance from anterior end to excretory pore of 43 (38-46) /xm, anterior end to end of pharynx of 116 (103-129) /xm; tail length of 50 (43-56) /xm, 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) /xm; 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. [ABSTRACT FROM AUTHOR]

Plesiotype specimens of the European dagger nematode, Xiphinema diversicaudatum, were collected in Saratov, Russia, and morphologically, morphometrically and molecularly characterised. PCR with specific primer was developed for rapid diagnostics of this species. Phylogenese relationships of X. diversicaudatum with other Xiphinema species, as inferred from the analyses of the D2-D3 expansion segments of 28S rRNA, ITS rRNA and coxl mtDNA gene sequences, are also provided. The study revealed that the clade X. diversicaudatum, together with X. bakeri (North America) and X. chengi (Asia), is related to Xiphinema species from the Mediterranean region and likely originated from a common ancestor inhabiting this area. The phylogenetic reconstructions with coxl mtDNA were used to describe the pattern of present genetic diversity of X. diversicaudatum and infer its biogeographical history in Europe. Haplotype diversity of X. diversicaudatum populations from Central Europe was significantly higher than those from southeastern Europe, central, south-eastern and southern European Russia. It has been hypothesised that, during the Last Glacial Maximum, X. diversicaudatum populations probably persisted in refuge areas in the Carpathian mountains or the Alps, the species subsequently expanding from these areas and colonising other regions in Europe. [ABSTRACT FROM AUTHOR]

A new species of Steinernema is described herein as S. bifurcatum n. sp. It is characterised by the presence of a male gubernaculum that is bifurcate at both proximal and distal ends, a key diagnostic feature. Steinernema bifurcatum n. sp. belongs to the bicornutum group by having two horn-like structures on the labial region of the infective juvenile (IJ). It can be recognised by IJ body diam. = 22 (20-24) /xm, pharynx = 114 (102-134) /xm, ratio a = 24 (22-25) and D% = 39.7 (33-47). The new species can be further recognised by the male characters of D% = 48 (42-58), and genital papillae = 23 (22 + 1) in number and, for the first generation female, excretory pore = 75.7 (60-108) /xm, pharynx = 174 (158-200) /xm and tail length = 43.2 (38-60) /xm. Steinernema bifurcatum n. sp. is distinguished from all other members of the bicornutum group by the presence of a gubernaculum which is bifurcated at both proximal and distal ends in first generation males. On the basis of genital papillae number (22+1) it is close to S. abbasi, S. ceratophorum and S. pakistanense, but can be distinguished by morphometries of IJ and adults. IJ of S. bifurcatum n. sp. can be differentiated from those of S. ceratophorum and S. pakistanense by the smaller body length of 460-590 /xm. Steinernema bifurcatum n. sp. differs from S. abbasi by morphological characters of IJ, male and female stages. The IJ can be distinguished by D% (33-47), body diam. (20-24) /xm, b value (3.8-5.6) and pharynx length (102-134) /xm. The second generation male differs by GS ratio (0.29-0.45) and the mucronate tail. The first generation female is distinguished by a protruding vulva and no postanal swelling. Analysis of ITS rDNA (824 bp), D2-D3 (880 bp) and mt DNA region (507 bp) sequences confirm that the studied nematode isolate represents a valid new species, the combination of molecular and morphological features indicating that it belongs to Clade IV, the bicornutum group. [ABSTRACT FROM AUTHOR]

Aphelenchoides rotundicaudatus n. sp. was isolated from packaging wood from South Korea imported to Ningbo harbour, China. Specimens were collected directly from wood samples using the Baermann method. Multiplication on Botryotinia fuckeliana failed. The new species has a body length of 364-509 μm (males) and 371-493 μm (females). The cuticle is weakly annulated and there are four lines in the lateral field. The stylet is 8-9 μm long and has small basal swellings. The excretory pore is located ca one body diam. anterior to median bulb. Spicules are small (10-13 μm), apex and rostrum rounded and only slight offset. The male tail has six (2 + 2 + 2) caudal papillae. Both male and female tails are cylindrical with a broadly rounded terminus, often with a small region of thickened cuticle or a blunt peg ca 1 μm long, particularly in the female. The new species belongs to the Group 1 category of Aphelenchoides species. Phylogenetic analyses based on full length ITS, partial LSU and SSU of rDNA confirmed its status as a new species. [ABSTRACT FROM AUTHOR]

Eubostrichus fertilis sp. n. is described from fine subtidal sands in the Belize Barrier Reef system using LM and SEM illustrations and the sequence of the 18S rRNA gene. The new species is one of the smallest (mature specimens ranging from 1.88 to 3.03 mm) and the stoutest (a = 36-80) of all previously described Eubostrichus species. The closest relatives are E. parasitiferus and E. hopperi. It differs from the former in the more posterior position of the vulva and the postanal porids, and from the latter in the smaller size of the amphids, the shorter cephalic setae and the shape of the tail. Furthermore, it is remarkable for the prominent extent of the female genital system. Females have up to 18 eggs of similar size in their uteri. The body of the worm is covered by large (up to 45 /xm long) crescent-shaped bacteria attached with both poles to the cuticle of the worm in a spiral pattern. The genus Eubostrichus is phylogenetically well supported on the basis of the 18S rRNA gene sequence. Eubostrichus gerlachi nom. nov. (= E. parasitiferus apud Gerlach, 1963 nec Chitwood, 1936) is proposed. [ABSTRACT FROM AUTHOR]

Study of Biology, Morphology and Taxonomy of the Nematode Stephanofilaria assamensis (Filariina, Stephanofilariidae). Saparov K. A., Akramova F. D., Azimov D. A., Golovanov V. I. - Biological characters of Stephanofilaria assamensis Pande, 1936, a parasite of cattle, were studied under environmental conditions of Uzbekistan with the emphasis on morphology of all developmental stages. Bloodsucking flies Haematobia atripalpis Bezzi, 1895, Lyperosia titillans Bezzi, 1907 and L.irritans Linnaeus, 1758 were established as intermediate hosts. Prevalence of the nematode larvae in the flies constituted 2.1, 1.5, and 1.2 %, respectively. Characters for the species identification were revised. On that basis S. zaheeri Singh, 1958 is regarded as a synonym of S. assamensis. The place of Stephanofilaria genus in the system of Stephanofilariidae is discussed. [ABSTRACT FROM AUTHOR]

Haemonchus contortus is a highly pathogenic nematode parasite of sheep and goats. This work was conducted to investigate the population and host variations of the parasitic nematode H. contortus of sheep and goats from Malaysia and Yemen. Eight morphological characters were investigated, namely the total body length, cervical papillae, right spicule, left spicule, right barb, left barb, gubernaculum and cuticular ridge (synlophe) pattern. Statistical analysis showed the presence of morphological variation between populations of H. contortus from Malaysia and Yemen, with minor variation in the synlophe pattern of these isolates. Isolates from each country were grouped together in the scatterplots with no host isolation. Body, cervical papillae and spicule lengths were the most important characters that distinguished between populations of the two countries. This variation between Malaysia and Yemen may be attributed to geographical isolation and the possible presence of a different isolate of this worm in each country. [ABSTRACT FROM AUTHOR]

Gnathostomatid nematodes identified morphologically as Spiroxys japonica Morishita, 1926 were collected from the dark-spotted frog Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae) in China. Light and scanning electron microscopy were used to study the morphology of this species in detail. Previously unreported morphological features are revealed and others corrected. In addition, adult nematodes of S. japonica collected from P. nigromaculatus and Spiroxys hanzaki Hasegawa, Miyata & Doi, 1998 collected from Andrias japonicus (Temminck) (Caudata: Cryptobranchidae) in China and Japan, respectively, and the third-stage larva of S. japonica collected from Lithobates catesbeianus (Shaw) (Anura: Ranidae) in Japan, were characterised using molecular methods by sequencing and analysing ribosomal [large ribosomal DNA (18S) and internal transcribed space] and mitochondrial [cytochrome c oxidase subunit 1] target regions, respectively. The new morphological and genetic data contributes to a more accurate diagnosis of this hitherto little known nematode genus. [ABSTRACT FROM AUTHOR]

Abstract: The taxonomic and functional structure of the subtidal nematode assemblages from a temperate estuary (Mondego estuary, Portugal) was studied, focussing on different taxonomic levels (genus, family and order), on single functional groups and on multiple biological traits. Based on taxonomic levels and on four biological traits (feeding type, life strategy, tail and body shape), the analysis of the nematode assemblage distribution patterns revealed spatial differences but no clear temporal pattern. At the family and genus level, a separation of the upstream sections was observed, while a distinction of polyhaline and euhaline areas was less evident. The use of biological traits added new information regarding the relationships between diversity patterns and the environmental variables. Most nematodes encountered along the estuary were non-selective deposit feeders (1B) and omnivores/predators (2B), colonizer–persisters (score of 2 or 3), with clavate-conicocylindrical tails and slender bodies and with a distribution related essentially to salinity, oxygen and chlorophyll a. Applying a Biological Traits Analysis (BTA) showed the role of oxygen concentration in the distribution of the nematode communities. Although the BTA was no more powerful than the traditional taxonomic approach in detecting spatial differences along the Mondego estuary, it has increased our knowledge of the functional structure and characterization of nematode communities in the estuary. [Copyright &y& Elsevier]

Iberian material ofMacrolaimus crucis, the type species of its genus, is described and illustrated based on light micropscope and scanning electron microscope observations. It is characterized by its body length, 654–863 μm in females and 654–767 μm in males; labial sensilla six conical setae forward directed; stoma nearly as long as wide (9–13 × 6–11 μm), with cheilostome slightly longer than gymnostome and cheilorhabdia and gymnorhabdia well developed; pharyngeal corpus 1.6–2.4 times isthmus length, with slightly swollen metacorpus; excretory pore located at isthmus level; female reproductive system prodelphic, lacking postvulval uterine sac; tail of both sexes conical (46–61 μm,c= 13.1–15.1,c′= 3.1–4.0 in females, 38–48 μm,c= 14.6–17.2,c′= 2.0–2.6 in males), ending in an acute and weakly bent dorsad tip, and phasmids at 60–70% of tail length; spicules 26–38 μm long; and gubernaculum 10–13 μm long. Iberian material is compared with type material and other known populations. The taxonomy of the genus is revised, including an emended diagnosis, an updated list of species, a key to their identification and a compendium of their morphometrics and diagnostic features. [ABSTRACT FROM PUBLISHER]

Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology. [ABSTRACT FROM AUTHOR]