Partial 18S Sequences Research Articles

Reaching new lands: Updating the distribution of Angiostrongylus cantonensis in South America with the first record in Argentina.

Angiostrongylus cantonensis, commonly known as the rat lungworm, is a metastrongyloid nematode found primarily not only in tropical and subtropical regions but also in temperate areas and considered the leading cause of eosinophilic meningitis in humans. Synanthropic rodents such as Rattus norvegicus and Rattus rattus are the most frequent definitive hosts of this parasite. The presence of this parasite was detected in the pulmonary arteries of three specimens of R. norvegicus in the city of Buenos Aires representing the species' southernmost known record in natural hosts. Species confirmation was achieved through partial sequences of 18S and COI genes. By comparing the COI gene sequences with those available in GenBank through the construction of a haplotype network, we obtained that the analysed specimen presents high similarity with those reported in Japan and Southeast Asia. All infected rats were captured in an area surrounding a port with significant import and export activity, suggesting that A. cantonensis may have been introduced through commercial ships. Specifically, the parasite was detected in a neighbourhood with vulnerable socio-economic conditions and in a nature reserve, which exhibit biotic and abiotic characteristics conducive to sustaining high-density rat populations, scattered waste, areas of spontaneous vegetation, debris accumulation and flooded areas or lagoons offering suitable habitats for intermediate hosts such as snails. Thus, the close proximity of the port to these sites creates a favourable ecological context for the establishment of A. cantonensis. This study shows the need to conduct research to detect A. cantonensis in non-endemic areas but with the characteristics that promote its arrival and development of its life cycle in order to implement control measures to prevent expansion of this parasite and its transmission to humans and other animals.

First Report of Powdery Mildew on Cardamine violifolia in China.

Cardamine violifolia, also called Cardamine hupingshanensis, is an economically important medicinal plant renowned for accumulating selenium (Guo et al., 2022). Selenium is an essential trace element with anti-oxidant, anti-inflammatory, anti-cancer, and immune regulatory functions. In July 2023, an outbreak of powdery mildew was detected, infecting the leaves of numerous C. violifolia plants in Enshi (30°11'5.27''N; 109°48'48.45''E), Hubei Province, China. This disease caused severe damage to plant leaves and stems, starting as individual spots and merging into a large mold that covers the entire leaf. It affected nearly 25% all C. violifolia plants, resulting in significant yield loss, disruption of normal metabolism, and premature aging. The lower leaf blades and underside of the leaves were particularly vulnerable. The affected leaves were collected and subjected to morphological diagnostic analysis (Mori et al., 2000) (Fig. S1). The powdery mildew species aggressively spread throughout the leaves, pedicels, and pods, persisting until present and often covering the entire surface. The conidiophores were upright, cylindrical, composed of 3 to 4 cells, and measured 92.3 ± 12.9 × 9.2 ± 0.6 μm (n = 30). Conidial pedicels had 21.6 ± 3.4 μm (n = 50) long cylindrical podocytes. The monoconidia were columnar or barrel-columnar, 30.60-55.59 × 9.11-20.00 μm in size. Conidia lacked an obvious cellulose body. The bud tubes formed from the end of conidia, and papillary appressoria developed on the epiphytic mycelia. ITS region sequences were amplified using the specific powdery mildew universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3'), PM6 (5'-GYCRCYCTGTCGCGAG-3') for partial sequences of 18S and 28S ribosomal DNA genes (Takamatsu et al., 2001). The sequence was deposited in the GenBank under the accession number OR506156 and aligned with available sequences on NCBI, which were 99.2%(528/532) identical to the E. cruciferarum (MT309701, MF192845, and KY660929) sequences (Fig. S2). The ITS sequence from GenBank was used to conduct maximum likelihood phylogenetic analysis using MEGA 11.0. The analysis results showed both the strain and E. cruciferarum clustered on the same branch. To confirm Koch's postulates, pathogenicity testing was carried out using an illuminating incubator. Infected leaves were attached to healthy leaves of C. violifolia seedlings (n=8). All the plants were incubated under 25℃ and >80% relative humidity. After one month, all inoculated plants presented the same symptoms as those initially observed in the field. Morphological and molecular analysis confirmed the isolated fungi's identity as the same pathogen. Therefore, C. violifolia is a suitable host for E. cruciferarum in China. The growers must be informed of these findings to prevent serious economic losses caused by this pathogenic white powder and to prepare for proper management practices. To our knowledge, this is the first report of E. cruciferarum infecting C. violifolia in China.

Redescription and First Nucleotide Sequences of Opecoeloides pedicathedrae (Digenea: Opecoelidae), a Parasite of Cynoscion leiarchus (Cuvier, 1830) (Eupercaria: Sciaenidae) from Brazil

Opecoeloides Odhner, 1928, is represented by 19 valid species found in marine fish, of which five have been reported in Brazil. Specimens of Opecoeloides pedicathedrae Travassos, Freitas & Bührnheim, 1966, were collected from the intestine of smooth weakfish Cynoscion leiarchus, a new host record, from off the coast of Rio de Janeiro, Brazil. They were examined using light and confocal laser microscopy. New partial sequences of 18S and 28S rDNA genes of O. pedicathedrae were obtained. Bayesian inference analysis on the partial 28S rDNA dataset resulted in a phylogram in which O. pedicathedrae formed a well-supported clade with Opecoeloides fimbriatus and Opecoeloides furcatus. The K2p distance between O. pedicathedrae and O. fimbriatus was 0.34%, with 3 divergent nucleotides; and between O. pedicathedrae and O. furcatus was 4.18%, with 38 divergent nucleotides. A Bayesian-inference phylogenetic tree based on the 18S rDNA recovered two main clades with five subfamilies. A clade of Opecoelinae showed that O. pedicathedrae was closer to Pseudopecoeloides tenuis; the K2p distance between these species was 2.14%, with 28 divergent nucleotides. The new nucleotide sequences presented inclusion of a phylogenetic analysis that can help to clarify the understanding of this complex taxon.

Molecular characterization of the nearly complete nuclear ribosomal DNA sequence of the Neotropical freshwater copepod Arctodiaptomus dorsalis (Marsh, 1907) (Copepoda, Calanoida, Diaptomidae)

Abstract Arctodiaptomus dorsalis has been reported in the Philippines as an invasive species, which originated from Central America. Apart from its wide distribution in the United States and Central America, it is now widely distributed in many lakes in the Philippine islands, such as Luzon Island and southwestern Mindanao, making it an ideal specimen for studies on population dynamics and population genetics. Recently, new techniques have been emerging as important zooplankton monitoring tools, such as metabarcoding and the use of environmental DNA/environmental RNA. However, these would only be useful if good-quality reference DNA sequences are available before utilizing these techniques. This study sequenced the nearly complete nuclear ribosomal DNA (nrDNA) of A. dorsalis from 202 individuals from Lake Taal, Batangas. The total length was 5887 bp, which includes the partial 18S sequences, and the complete 5.8S, ITS and 28S sequences with an organization that is typical for any eukaryotic organism. This is the first record of a nearly complete nrDNA sequence for freshwater calanoid copepods and is considered an important stepping stone for further molecular studies in freshwater Copepoda.

Molecular identification and phylogenetics of local pearl millet cultivars using internal-transcribed spacers of nuclear ribosomal DNA

AbstractLocal cultivars of pearl millet in Saudi Arabia are known to tolerate extreme heat and drought stress. In the current study, the sequences of internal-transcribed spacers (ITSs) of six pearl millet cultivars were sequenced and analysed to investigate the genetic diversity among the local cultivars. The nucleotide polymorphism, secondary structures and phylogenetics were analysed for ITS sequences of the six local cultivars. The obtained sequences were 772–774 base pairs (bp) in length, including complete sequences of the ITS1–5.8S–ITS2 region and partial sequences of 18S and 26S rRNA. The nucleotide diversity among cultivars was higher in ITS2 sequences than ITS1 sequences. The ITS2 had four variable nucleotide sites in three native cultivars, whereas the ITS1 contained one base insertion. The secondary structures of the ITS1 and 5.8S region were highly conserved among the six cultivars and contained some motifs that are conserved across Viridiplantae. However, the ITS2 secondary structure for the two native cultivars, Sayah and Jazan, was distinct from the other cultivars, which confirms the applicability of the ITS2 sequence in distinguishing between genetically close taxa. Additionally, the phylogenetic analysis of the six investigated cultivars and 31 pearl millet accessions from the NCBI database showed close relationships between the local accessions and NCBI accessions from India and France. However, the local cultivar Sayah appeared to be distinct from the other cultivars in the phylogenetic trees. This study provides insights into the polymorphism within local pearl millet cultivars which is important for the identification and conservation of these cultivars.

Quinquelaophonte enormis sp. nov., a new interstitial copepod (Harpacticoida: Laophontidae) from Korea.

We collected an undescribed laophontid copepod from a coarse sand habitat on the east coast of Korea and named it Quinquelaophonte enormis sp. nov. We compared the detailed morphological characteristics of the new species with those of congeneric species. Among them, the new species shows a superficial resemblance to the Californian species Quinquelaophonte longifurcata Lang, 1965. However, the two species are easily distinguishable by the setation of the syncoxa on the maxilliped and the fourth swimming leg. The new species has the variable setation on the second to fourth swimming legs. The variations appear among individuals or between the left and right rami of a pair of legs in a single specimen. Although complex chaetotaxical polymorphism occur in this new species, we used myCOI and Cytb to confirm that the new species is not a species complex. Also, partial sequences of 18S and 28S ribosomal RNA genes were used to analyze the position of the new species within the family Laophontidae. The new speciesis the fourteenth Quinquelaophonte species in the world and the second species in Korea.

Contributions to the knowledge of Pseudolevinseniella (Trematoda: Digenea) and temnocephalans from alien crayfish in natural freshwaters of Thailand

Redclaw crayfish (Cherax quadricarinatus) is a decapod species originating from Australian freshwater. For more than two decades, these crayfish have been re-distributing to environments in many countries, including Thailand. Moreover, they can carry endosymbionts and/or ectosymbionts into new environments. The aim of this study was to introduce a morphological description of Pseudolevinseniella anenteron as a metacercaria of the endoparasites of redclaw crayfish collected from natural water sources in Thailand. The occurrence of two ectosymbiotic temnocephalans (Diceratocephala boschmai and Temnosewellia sp.) in C. quadricarinatus was also reported. The internal morphology of P. anenteron, D. boschmai and Temnosewellia were described and discussed. The surface ultrastructure of the multidentate spines on the body and the metacercarial cyst wall of P. anenteron was investigated by scanning electron microscopy (SEM). By performing a search of the GenBank nucleotide database of partial sequences of 18S, 28S rDNA and cytochrome c oxidase subunit I (cox1), P. anenteron was found to be related to Maritrema, and Temnosewellia was found to be related to T. fasciata. However, according to the cox1 gene, Temnosewellia was found to be similar to T. minor. These results reveal that redclaw crayfish that inhabit natural freshwaters in Thailand may harbour endoparasites and ecto- and endosymbionts. Furthermore, these findings may be able to monitor invasive or non-invasive species in an ecosystem.

The impact of a new genus on the molecular phylogeny of Hemisphaeriini (Hemiptera, Fulgoromorpha, Issidae).

A new genus, Retaldargen. nov. of the family Issidae (Hemisphaeriinae, Hemisphaeriini) is described from Guangxi Province of China. A revised molecular analysis for the Hemisphaeriini based on partial sequences of 18S, 28S, COXI and Cytb, provides evidence for a new lineage within the subtribe Mongolianina. With two subgroups of genera now identified, the monophyly of Mongolianina is discussed from both a morphological and a molecular basis.

Redescription and First Nucleotide Sequences of Rhinobatonchocotyle pacifica Oliva & Luque, 1995 (Monogenea: Hexabothriidae), a Parasite of Pseudobatos planiceps (Garman, 1880) (Rhinopristiformes: Rhinobatidae) from Peru.

Specimens of Rhinobatonchocotyle pacifica Oliva & Luque, 1995 (Hexabothriidae) were collected from the gill filaments of Pacific guitarfish, Pseudobatos planiceps (Garman, 1880) (Rhinopristiformes: Rhinobatidae), from off the coast of Chorrillos, Lima, Peru. Since the original description of R. pacifica was incomplete, we herein redescribe R. pacifica based on re-examination of the holotype, paratypes, and newly collected voucher specimens. Nucleotide sequences (18S, 28S) for R. pacifica are presented for the first time, and a phylogenetic analysis conducted. Monogeneans were examined with light microscopy and partial sequences of 18S and 28S rDNA genes were obtained. The following taxonomically important morphological features are described: presence of seminal receptacle, spiniform papillae within oral cavity, haptoral sucker sclerites and anchors, hook surface striations, muscular pad associated with each haptoral sucker sclerite (except sclerite 1), muscular bulbs in appendix suckers, and oötype lacking longitudinal rows of large cells (oötype not côtelé). The genital complex is detailed. The diagnosis of Rhinobatonchocotyle is emended to include species with or without seminal receptacle. Representative nucleotide sequences of partial 18S and 28S rDNA genes of R. pacifica were obtained for the first time and used for reconstructing the phylogeny of Hexabothriidae. The phylogenetic reconstruction confirmed the species within the Hexabothriidae.

A New Species of the Acanthocephalan Genus Filisoma (Cavisomidae) from Perciform Fishes in Rio de Janeiro, Brasil

BackgroundTwelve species of Filisoma Van Cleave, 1928 are recognized parasitizing tropical and subtropical fish. Four of these species were described from kyphosid fish and it has been suggested that a co-speciation may have occurred among species of Kyphosus Lacepède, 1801 and Filisoma, which could provide valuable information about the evolution history of this host–parasite system.PurposeDuring a survey of the helminth fauna of Kyphosus sectatrix (Linnaeus, 1758) and Kyphosus incisor (Cuvier, 1831) (Kyphosidae Jordan, 1887) off Rio de Janeiro coast, a new species of Filisoma was found and is described herein based on morphological, genetic, and ultrastructural data.MethodsFish were obtained off Rio de Janeiro coast, Brazil. The parasites found in the intestine were measured and drawings were made with a drawing tube. Type specimens were deposited at the Helminthological Collection of Oswaldo Cruz Institute (CHIOC). The ultrastructure was studied using scanning electron microscope. The genetic analysis included the study of the partial sequences of 18S, ITS1, 5.8S and 28S rDNA, and the mitochondrial cytochrome c oxidase 1 gene (cox 1), with phylogenetic reconstructions based on the maximum likelihood analysis.ResultsFilisoma caudata n. sp. is characterized by a proboscis with 16‒18 longitudinal rows of 38‒45 hooks each. Hooks are uniform in shape dorsoventrally, gradually decreasing in size towards the base of the proboscis. Anterior hooks are 30‒45 μ long, middle hooks 30‒35 μ long and 5 basal transversal hooks 20‒30 μ long. The new species is differentiated from the closest species Filisoma filiformis Weaver and Smales, 2013 by the size and distribution of hooks, apart from having a subterminal vulva and a curved posterior trunk end (tail) measuring 500‒1,000 long. Phylogenetic analysis based on 18S, 28S rDNA and mtDNA-cox1 markers grouped the new species with Filisoma bucerium Van Cleave, 1940 and Filisoma rizalinum Tubangui and Masiluñgan, 1946 showing a close relationship between these species of Cavisomidae Meyer, 1932 and Echinorhynchidae Cobbold, 1879; the latter represented by species of Acanthocephalus Koelreuther, 1771. The new species can be differentiated from others on morphological and molecular basis. A key to the 13 species of Filisoma Van Cleave, 1928 is provided.ConclusionFilisoma caudata n. sp. is described herein based on morphological, genetic, and ultrastructural data. The topologies of obtained phylogenies suggest that species of Echinorhynchidae should be reevaluated since the family is considered paraphyletic in all analyses conducted.

Bursaphelenchus crenati Rühm, 1956 (Tylenchina: Aphelenchoididae), a nematode associated with the Greater ash bark beetle, Hylesinus crenatus Fabricius, in dying ash, Fraxinus excelsior L., in Europe

New morphological, molecular and bionomic data are added to update the description of Bursaphelenchus crenati. The nematode was isolated from larval galleries and adults of the Greater ash bark beetle, Hylesinus crenatus Fabricius, present in bark of older trees of European ash, Fraxinus excelsior L., in Poland. Detailed female and male morphology are documented in this paper and compared with the original description. From ITS1/2, partial 28S D2-D3 and partial 18S sequences, ITS-RFLP patterns and morphological analysis, B. crenati is suggested to be temporarily placed into the sexdentati group, close to B. andrassyi, B. vallesianus, B. sexdentati, B. pinophilus, B. poligraphi, B. fuchsi, B. incurvus, B. piniperdae, and B. pityogeni. However, B. crenati can be distinguished from these species by the strongly ventrally curved body and the presence of three incisures in the lateral fields.

Fifteen novel universal primer pairs for sequencing whole chloroplast genomes and a primer pair for nuclear ribosomal DNAs

AbstractChloroplast genome information helps improve the phylogenetic resolution and can act as organelle‐scale barcodes in recently radiated plant groups. Previously we reported that nine universal primer pairs could amplify angiosperm whole chloroplast genomes by long‐range polymerase chain reaction and using next‐generation sequencing. Although these primers show high universality and efficiency for sequencing whole chloroplast genomes in angiosperms, they did not fully resolve the following two issues surrounding sequencing angiosperm chloroplast genomes: (i) approximately 30% of angiosperms cannot be amplified successfully; and (ii) only fresh leaves can be applied. In this study, we designed another set of 15 universal primer pairs for amplifying angiosperm whole chloroplast genomes to complement the original nine primer pairs. Furthermore, we designed a primer pair for nuclear ribosomal DNAs (nrDNAs). To validate the functionality of the primers, we tested 44 species with silica gel‐dried leaves and 15 species with fresh leaves that have been shown to not be amplified with the original nine primer pairs. The result showed that, in 65.9% and 88.6% of the 44 species with silica gel‐dried leaves, the whole chloroplast genome and nrDNAs could be amplified, respectively. In addition, all 15 fresh leaf samples could have the whole chloroplast genome successfully amplified. The nrDNAs comprise partial sequences of 18S and 26S, along with the complete sequence of 5.8S and the internal transcribed spacers ITS1 and ITS2. The mean size of nrDNA was 5800 bp. This study shows that the 15 universal primer set is an indispensable tool for amplifying whole chloroplast genomes in angiosperms, and these are an important supplement to the nine reported primer pairs.

Structure of intestinal helminth communities of the striped dolphin, Stenella coeruleoalba, in the western Mediterranean: a long-term analysis

Structure of intestinal helminth communities of the striped dolphin, Stenella coeruleoalba, in the western Mediterranean: a long-term analysis

Rotylenchus cretensis n. sp. and R. cypriensis Antoniou 1980 (Nematoda: Hoplolaimidae) recovered from the rhizosphere of olive at Crete (Greece) with a molecular phylogeny of the genus

A new and a known species of Rotylenchus from Crete, each collected from the rhizosphere of olive, are described and illustrated based on morphological, morphometric and molecular studies. Rotylenchus cretensis n. sp. is characterised by having a truncate lip region with irregular longitudinal striation, lateral field areolated only in pharynx region, stylet length less than 41 μm, vulva located at 53–59 %, conoid-rounded to dorsally convex-conoid female tail with 7–11 annuli and specific D2-D3 of 28S, ITS, and partial 18S rRNA. Rotylenchus cretensis n. sp. appears to be similar to R. urmiaensis, having overlapping character ranges. Rotylenchus cretensis is also similar to R. striaticeps from which has got shorter stylet length (35.5–41.5 vs 39–50 μm), female tail shape (conoid-rounded to dorsally convex-conoid vs rounded), shorter spicules length (34–40 vs 41–50 μm), and phasmid position (varying from at level to three annuli posterior to the anus vs at level to seven annuli anterior to anus). Multivariate analysis of variance performed on R. cretensis n. sp., as well as two populations of R. striaticeps and R. urmiaensis from Iran on combined morphometric characters data set revealed a significant effect by species populations, indicating that closely morphological and morphometrically species differed significantly from each other. Additionally, analysis of variance showed that morphometric characters such as lip region width, distance from phasmid to tail tip (PHS) or a ratio can be used as key morphometric characters for species differentiation in this group. The results of phylogenetic analyses based on D2-D3 region, ITS of rRNA, and the partial 18S sequences confirmed the close molecular relationships between R. cretensis n. sp., R. urmiaensis and R. striaticeps, but clearly support the proposal of R. cretensis n. sp. as a new species. Also, the recognition of this cryptic species within Rotylenchus shows that the biodiversity of these nematodes is still not fully understood and requires further studies. Additionally, R. cypriensis is described and molecularly analysed for first time in Greece.

A molecular reappraisal of Nimbospora (Halosphaeriaceae, Microascales) and a new genus Ebullia for N. octonae

Nimbospora is a genus in the Halosphaeriaceae with three species: N. effusa (the type species), N. bipolaris and N. octonae. All species have two-celled ascospores with a prominent sheath. A second type of appendage is present in two species, a single tuft of fibrillar appendages is present in N. effusa and two occur in N. bipolaris. Nimbospora effusa and N. bipolaris are morphologically similar, but there are major morphological differences in ascomatal morphology between N. effusa/N. bipolaris and N. octonae. In this study, we investigated the morphology of N. effusa and N. octonae and the phylogenetic relationships of the three Nimbospora species based on partial sequences of 18S and 28S rRNA genes. Bayesian analysis suggested that Nimbospora is not monophyletic. Nimbospora effusa groups with N. bipolaris in a well-supported clade, with Naufragella spinibarbata forming a sister group. Nimbospora octonae, however, clusters with Haligena elaterophora in a separate, well-supported clade. The ascomata of N. octonae differ from those of N. effusa and N. bipolaris by their thick peridium, and ascospores that lack equatorial tufts of appendages but possess polar and equatorial subulate appendages after the sheath is dissolved. Based on these characters and the correlating phylogenetic distance, the new genus Ebullia is established to accommodate N. octonae.

Brettanomyces yeasts isolated from lebanese wines showing difference in their molecular pattern

The action of Brettanomyces yeast is a leading cause for organoleptic alterations of wine. To evaluate the presence of this yeast in Lebanon, 100 red wine samples selected from 14 wineries located in different regions of the Lebanese territory, were analyzed. Only 3 samples gave positive results. A first PCR showed that all isolates belonged to the species B. bruxellensis. Strains profiles were compared to 2 other French isolates. The PCR-RFLP was then used with 3 endonucleases for an inter-species characterization. The obtained results revealed a degree of polymorphism between strains isolated from different geographical origins. A comparison of the sequence of ITS regions, including the 5.8S rDNA and partial sequences of 18S and 28S rDNA illustrate potential similarities or differences between strains belonging to the same group.

The phylogenetic position of the Loimoidae Price, 1936 (Monogenoidea: Monocotylidea) based on analyses of partial rDNA sequences and morphological data

Phylogenetic analyses of partial sequences of 18S and 28S rDNA of some monogenoids, including monocotylids and a specimen of Loimosina sp. collected from a hammerhead shark off Brazil, indicated that the Loimoidae (as represented by the specimen of Loimosina sp.) represents an in-group taxon of the Monocotylidae. In all analyses, the Loimoidae fell within a major monocotylid clade including species of the Heterocotylinae, Decacotylinae, and Monocotylinae. The Loimoidae formed a terminal clade with two heterocotyline species, Troglocephalus rhinobatidis and Neoheterocotyle rhinobatis, for which it represented the sister taxon. The following morphological characters supported the clade comprising the Loimoidae, Heterocotylinae, Decacotylinae and Monocotylinae: single vagina present, presence of a narrow deep anchor root, and presence of a marginal haptoral membrane. The presence of cephalic pits was identified as a putative synapomorphy for the clade (Loimoidae (T. rhinobatidis, N. rhinobatis)). Although rDNA sequence data support the rejection of the Loimoidae and incorporating its species into the Monocotylidae, this action was not recommended pending a full phylogenetic analysis of morphological data.

Morphological and Molecular Features ofPunctodera stoneiBrzeski, 1998 (Nematoda: Heteroderidae) — Species Associated with Roots of Grasses

This article provides morphological and molecular characteristics of Punctodera stonei Brzeski, 1998. Comparison of partial sequences of 18S and 28S rDNA genes from P. stonei sampled in Poland and Punctodera sp. from Canada showed their 100% similarity. This is the first report on the occurrence of P. stonei outside of Europe. We provide data on morphology of males and 2nd stage juveniles of this species and an identification key to males of the genus Punctodera Mulvey et Stone, 1976. Moreover, the paper presents evolutionary relationships of P. stonei within the family Heteroderidae.

Morphological and molecular characterization of Gordionus alpestris (Nematomorpha) from the North-West Caucasus, Russia

Abstract During the survey of Pachyiulus krivolutskyi Golovatch, 1977 (Diplopoda) near Nickel’ in Adygei Republic (Russia) in the summer 2009 the infestation of these millipeds with nematomorphs of the species Gordionus alpestris was revealed. The morphology of naturally emerging nematomorphs was studied in SEM. The partial sequences of 18S (883 bp) and 28S (393 bp) rDNA PCR-products were obtained and analyzed. An unexpectedly high level of differences between Gordionus alpestris found in diplopods of North-West Caucasus and other molecularly studied representatives of the family Chordodidae was observed.

Molecular characterization of kudoid parasites (Myxozoa: Multivalvulida) from somatic muscles of Pacific bluefin (Thunnus orientalis) and yellowfin (T. albacores) tuna

The public health importance of Kudoa infection in fish remains unclear. Recently in Japan a Kudoa species, K. septempunctata, was newly implicated as a causative agent of unidentified food poisoning related to the consumption of raw olive flounder. Other marine fishery products are also suspected as causative raw foods of unidentified food poisoning. For this study, we detected kudoid parasites from sliced raw muscle tissues of a young Pacific bluefin and an adult yellowfin tuna. No cyst or pseudocyst was evident in muscles macroscopically, but pseudocysts were detected in both samples histologically. One substitution (within 1100 bp overlap) and ten substitutions (within 753 bp overlap) were found respectively between the partial sequences of 18S and 28S rDNAs from both isolates. Nucleotide sequence similarity searching of 18S and 28S rDNAs from both isolates showed the highest identity with those of K. neothunni from tuna. Based on the spore morphology, the mode of parasitism, and the nucleotide sequence similarity, these isolates from a Pacific bluefin and a yellowfin tuna were identified as K. neothunni. Phylogenetic analysis of the 28S rDNA sequence revealed that K. neothunni is classifiable into two genotypes: one from Pacific bluefin and the other from yellowfin tuna. Recently, an unidentified kudoid parasite morphologically and genetically similar K. neothunni were detected from stocked tuna samples in unidentified food poisoning cases in Japan. The possibility exists that K. neothunni, especially from the Pacific bluefin tuna, causes food poisoning, as does K. septempunctata.