Partial 16S rDNA Sequencing Research Articles

Uncharted digenean diversity in Lake Tanganyika: cryptogonimids (Digenea: Cryptogonimidae) infecting endemic lates perches (Actinopterygii: Latidae)

BackgroundLake Tanganyika is considered a biodiversity hotspot with exceptional species richness and level of endemism. Given the global importance of the lake in the field of evolutionary biology, the understudied status of its parasite fauna is surprising with a single digenean species reported to date. Although the most famous group within the lake’s fish fauna are cichlids, the pelagic zone is occupied mainly by endemic species of clupeids (Actinopterygii: Clupeidae) and lates perches (Actinopterygii: Latidae, Lates Cuvier), which are an important commercial source for local fisheries. In this study, we focused on the lake’s four lates perches and targeted their thus far unexplored endoparasitic digenean fauna.MethodsA total of 85 lates perches from four localities in Lake Tanganyika were examined. Cryptogonimid digeneans were studied by means of morphological and molecular characterisation. Partial sequences of the nuclear 28S rRNA gene and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were sequenced for a representative subset of the specimens recovered. Phylogenetic analyses were conducted at the family level under Bayesian inference.ResultsOur integrative approach revealed the presence of six species within the family Cryptogonimidae Ward, 1917. Three out of the four species of Lates were found to be infected with at least one cryptogonimid species. Two out of the three reported genera are new to science. Low interspecific but high intraspecific phenotypic and genetic diversity was found among Neocladocystis spp. Phylogenetic inference based on partial 28S rDNA sequences revealed a sister group relationship for two of the newly erected genera and their close relatedness to the widely distributed genus Acanthostomum Looss, 1899.ConclusionsThe present study provides the first comprehensive characterisation of the digenean diversity in a fish family from Lake Tanganyika which will serve as a baseline for future explorations of the lake’s digenean fauna. Our study highlights the importance of employing an integrative approach for revealing the diversity in this unique host-parasite system.

Diversity and geographical distribution of resting stages of eukaryotic algae in the surface sediments from the southern Chinese coastline based on metabarcoding partial 18S rDNA sequences

AbstractSurface sediment samples were collected from sixteen sites of the southern Chinese coastline in this study. Diversity of eukaryotic microalgae was examined using high‐throughput sequencing of 18S rDNA to understand the community structure and geological distribution of microalgal resting stages. A total of 218 operational taxonomic units (OTUs) were detected for eukaryotic algae, and only 75 OTUs (34.40%) were detected into species level. The algal communities were composed of sixty‐four genera belonged to twelve classes of four phyla. Dinoflagellates were the most abundant and diversified group, which accounted for the average of 56.26% and 53.70% DNA reads and OTUs, respectively. Dinoflagellates were dominated by Protoperidinium, Euduboscquella, Amylax, and Paragymnodinium. Chaetoceros, Thalassiosira, and Skeletonema were abundant in diatoms, while Pedospumella and Paraphysomonas in Chrysophyceae were the most abundant genera due to their massive occurrence in some particular sites. The high abundance of Protoperidinium sequences suggested the high nutrient levels in the southern Chinese coastline. Nineteen of the detected OTUs were assigned to harmful and/or bloom‐forming microalgae. The wide occurrence of the toxic dinoflagellate Azadinium poporum and high abundance of Alexandrium pacificum in some particular sites suggested the potential risk of human poisoning.

Morphological and molecular characterization of Maritrema kostadinovae n. sp. (Digenea: Microphallidae) from the yellow-crowned night heron Nyctanassa violacea (Aves: Ardeidae) in Mexico.

A new species of microphallid trematode was collected from the intestine of the yellow-crowned night heron Nyctanassa violacea (L.) (Pelecaniformes: Ardeidae) from Veracruz, Mexico. Maritrema kostadinovae n. sp. differs distinctly from other members of Maritrema Nicoll, 1907 from the Americas by its smaller body size (262-435 × 242-363μm), the extension of caeca (reaching to anterior level of ventral sucker), the size and shape of the cirrus (short, tubular and unarmed) and metraterm (simple and thin-walled), the position of the genital pore (sinistrolateral to ventral sucker) and the arrangement of the vitellaria (horseshoe-shaped with posteriorly directed opening). Maximum likelihood and Bayesian inference analyses, based on partial 28S rDNA sequences, depicted M. kostadinovae n. sp. within the genus Maritrema with strong support. The new species is in a sister position to other available members of Maritrema, except for M. subdolum Jägerskiöld, 1909 that branches as the early divergent species in the Maritrema clade. The new species is the third species of Maritrema described from birds in Mexico. Comparative morphometric data for Maritrema taxa from birds and mammals from the Americas is provided.

Process optimization and characterization of polyhydroxyalkanoate copolymers produced by marine Pichia kudriavzevii VIT-NN02 using banana peels and chicken feather hydrolysate

Abstract The present study was focused on the production of polyhydroxyalkanoates (PHA) by halophilic yeast using biowaste materials. The yeast strain was isolated from marine seaweeds and identified as Pichia kudriavzevii VIT-NN02 based on partial 18SrDNA sequencing and phylogenetic analysis. PHA granules were observed by Sudan Black B and Nile Red staining methods. Banana peels and chicken feathers hydrolysate were screened as potential carbon and nitrogen sources for PHA content in biomass (%) by P. kudriavzevii. Process parameters were optimized using 3-level, six variables, Box-Behnken design showing significant improvement in PHA content in biomass from 40.00 ± 0.1 to 79.68 ± 0.2% under optimized growth conditions viz. banana peel extract (40%), salt (16.6gL-1), incubation time (96 h), pH (10), temperature (37 °C) and chicken feather hydrolysate (0.80%). The statistical significance of the model equation was calculated by F-test and R2 values of the respective responses were found to be 0.9904 and 0.9926, indicating a realistic fit of the model to the experimental data. The actual values of the PHA content in biomass (79.68 ± 0.2%) was in close agreement to the predicted value (79.68 ± 1.5%), confirmed the validity of the model. The biopolymer was identified as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] copolymer based on Gas Chromatography-Mass Spectrometry (GC-MS), Fourier Transform Infrared (FTIR) spectroscopy and Nuclear Magnetic Resonance spectroscopy (NMR) analysis. The [P(3HB-co-3HV)] copolymer was found to be highly crystalline and thermally stable through X-Ray Diffraction (XRD), Thermogravimetric analysis (TGA) and Differential scanning calorimetric (DSC) analysis. The Scanning Electron Microscopic (SEM) images of [P(3HB-co-3HV)] copolymer showed porous, smooth and spherical surface morphology.

Antibacterial activity of acroporid bacterial symbionts against White Patch Disease in Karimunjawa Archipelago, Indonesia

White Patch Disease (WPD), also known as White Pox, is a coral disease common in the Caribbean. Recently, it was observed for the first time in the Karimunjawa Archipelago, Indonesia. The lethal disease is characterized by patchy necrosis found all over the coral colony. We screened and characterized 87 isolates derived from 9 species of healthy coral-associated bacteria for their anti-pathogenic activity against WPD. Forty-nine out of 87 strains inhibited the growth of Halomonas meridiana and Virgibacillus salarius, the WPD associated bacteria isolated from infected Acropora muricata coral. The antipathogenic activity was re-screened using the disc diffusion method. BMT4 and BAF4 isolates displayed the strongest antibacterial activity and thus studied further. Partial sequencing of 16S rDNA showed that BMT4 and BAF4 isolates have a strong relationship with Bacillus flexus strain NBRC15715 and Lysobacter arseniciresistens strain ZS79. In addition, different types of WPD-associated bacteria were investigated. Various bacterial phylotypes of Acropora demonstrated antipathogenic ability thus indicating their potential role as bio-control agents against WPD from the Karimunjawa Archipelago.

Three new species of Allobacciger Hafeezullah & Siddiqi, 1970 (Digenea: Monorchiidae) from Australia and French Polynesia

Three new monorchiid trematodes are reported from fishes of the families Nemipteridae and Pomacanthidae; two species are described from the southern Great Barrier Reef and the third from off Moorea, French Polynesia. Allobacciger polynesiensis sp. nov. is described from Centropyge flavissima (Cuvier), Allobacciger brevicirrus sp. nov. from Scolopsis bilineata (Bloch) and Scolopsis margaritifera (Cuvier), and Allobacciger annulatus sp. nov. from Centropyge tibicen (Cuvier), Centropyge vroliki (Bleeker) and Centropyge bicolor (Bloch). The three species most closely resemble the type-species, Allobacciger macrorchis Hafeezullah & Siddiqi, 1970, as well as Allobacciger centropygis Machida & Uchida, 2001, differing primarily in the morphology of the terminal genitalia and excretory vesicle. With the introduction of these new species, the most recent generic concept does not accurately reflect all species in the genus, and we provide a revised generic diagnosis to accommodate the new taxa. Complete ITS2 rDNA, partial 28S rDNA, partial 18S rDNA and partial cox1 mtDNA sequence data were generated for the three new species; all markers distinguish the three species reported here unambiguously. Phylogenetic analyses of the new sequence data show that the three new species of Allobacciger Hafeezullah & Siddiqi, 1970 form a well-supported clade.

Four New Species of Paraorygmatobothrium (Eucestoda: Phyllobothriidea) from Sharks of the Gulf of Mexico and the Atlantic Ocean, with Comments on Their Host Specificity

Four new species of Paraorygmatobothrium are described from carcharhinid shark species from the Gulf of Mexico and the U.S. coast of the northwestern Atlantic Ocean. Paraorygmatobothrium bullardi n. sp. is described from Carcharhinus brevipinna as its type host, and from Carcharhinus acronotus and Carcharhinus limbatus. Paraorygmatobothrium campbelli n. sp. is described from Rhizoprionodon terraenovae. Paraorygmatobothrium deburonae n. sp. is described from Carcharhinus isodon as its type host, as well as from C. brevipinna, C. limbatus, and R. terraenovae. Paraorygmatobothrium mattisi n. sp. is described from R. terraenovae as its type host, and from C. brevipinna and C. limbatus. These 4 species differ from other species of Paraorygmatobothrium and from each other in bothridial microthrix shape, and in various combinations of features such as the total length of the worm, apical sucker size, bothridial musculature, proglottid number, testes number, and genital pore position. Difficulty in differentiating these 4 species from one another, and from other species of Paraorygmatobothrium, points to limitations in the use of morphology alone to recognize species diversity in this genus. A phylogenetic analysis of Paraorygmatobothrium and related genera, based on partial (D1-D3) 28S rDNA sequence data, confirms that the genus is not monophyletic. Genetic distances of COI revealed that sequence divergence between species of Paraorygmatobothrium is generally at least an order of magnitude larger than COI divergence within a species. Patterns of host use for 3 of the new species are consistent with previous findings that point to a lack of host specificity in Paraorygmatobothrium.

Extent of pathogenic and spoilage microorganisms in whole muscle meat, meat products and seafood sold in Libyan market.

Background:Whole muscle meat, meat products, and seafood contain different nutrients in adequate quantity providing a better environment for presence and replication of different microorganisms. There are underreported and inaccurate estimations of foodborne diseases due to the lack of effective surveillance systems in Libya.Aim:To determine the extent of microbiological contamination of whole muscle meat, meat products, and seafood.Methods:A total number of 731 samples of retail meat were collected from different stores in four cities in Libya. Samples were analyzed for aerobic plate count and subjected to microbiological enumeration and isolation techniques, followed by molecular identification by PCR and partial sequencing of 16S rDNA.Results:The results showed contamination of samples with enteric and spoilage bacteria. Fifteen genera of spoilage bacteria yielded 149 isolates which were detected and identified by PCR and partial sequencing of 16S rDNA as: Proteus spp., Provedencia spp., Raouttella ornithinolytical, Citrobacter spp., Enterobacter spp., Morganella morgi, Shewanella algea, Rhodobacter capsulatus, Listonella pelagia, Kluyvera spp., Pectobacterium spp., Brenneria spp., Klebsiella spp., Acintobacter radioresistens, and Pantoea spp. While for pathogenic bacteria, 143 isolates distributed among nine genera were identified by PCR and partial sequencing of 16S rDNA as: Bacillus spp., Escherichia spp., Shigella spp., Enterococci spp., Cronobacter spp., Staphylococci spp., Salmonella spp., Aeromonas spp., and Vibrio spp.. Many isolated bacteria are zoonotic bacteria with high importance for public health.Conclusion:Excessive handling and processing of meat and meat products seems to be one of the poorest microbiological qualities. These findings ought to be helpful in risk assessments and quality assurance of meat in order to improve food safety.

Neohexostoma gymnosardae n. sp. (Monogenea, Hexostomatidae), a gill parasite of Gymnosarda unicolor (Valenciennes) (Teleostei, Scombridae) in the South China Sea.

Parasite biodiversity of fish in coral reefs of the South China Sea is still incompletely explored. We describe here a new species of Neohexostoma (Monogenea: Hexostomatidae) from the gill filaments of the dogtooth tuna Gymnosarda unicolor (Scombridae), collected off Yongshu Reef, South China Sea. Neohexostoma gymnosardae n. sp. is distinguished from its congeners by the following features: (i) haptor clearly marked from body proper by a strongly constricted peduncle, divided in its posterior margin into two symmetrical lobes, (ii) vagina armed with scattered small blunt spines, (iii) eggs tied by their long polar filaments, (vi) esophagus with several lateral diverticula, (v) intestinal ceca unfused and extending into the haptor. We present an analysis of the relationships of this monogenean based on partial 28S rDNA sequences. An identification key for species of Neohexostoma is provided. This is the first member of the genus Neohexostoma known to parasitize a species of Gymnosarda.

Exploring species diversity of lissorchiid trematodes (Digenea: Lissorchiidae) associated with the gravel snail, Lithoglyphus naticoides, in European freshwaters.

Comparative analysis using complete ITS2 and partial 28S rDNA sequence data revealed that cercariaeum developing in rediae in Lithoglyphus naticoides represent two different lissorchiid species. One morphotype of cercariaeum is conspecific with adult Palaeorchis incognitus from European roach, Rutilus rutilus. The other cercariaeum is attributable to the genus Asymphylodora, but the species identity is not yet determined. We also generate the first rDNA sequences for Asymphylodora progenetica based on new collections from Bithynia tentaculata from Lithuania. Phylogenetic analyses of the newly generated sequences, together with information for other lissorchiids available on GenBank, showed that all representatives of Lissorchiidae form a strongly supported clade. Three monophyletic lineages, Asymphylodora, Palaeorchis and Lissorchis, were recognized at the generic level. Karyological analysis of the chromosome set of larval P. incognitus revealed a diploid number of 2n = 20. Its karyotype with subtelocentric chromosomes prevailing can be regarded as comparatively 'primitive', which is consistent with the basal position of P. incognitus in the 28S tree relative to the representatives of the genus Asymphylodora. The present study adds significant new information for establishing species-specific markers for the confident characterization of different developmental stages of lissorchiid species and clarification of their life cycles.

Biochar and PGPR amendments influence soil enzyme activities and nutrient concentrations in a eucalyptus seedling plantation

PGPR is widely used to improve the capacity of soil nutrient retention, which is closely related to soil microbial activity and enzyme activity. Biochar amendment can alter soil physicochemical properties, such as soil pH and the capacity of water holding. We conducted a study in Guangxi, China, in January 2018 to determine the responses of soil nutrient concentrations and enzyme activities to PGPR and biochar applications in a eucalyptus plantation. Bacillus megatherian strain Du07 was isolated from eucalyptus rhizosphere soil and was confirmed to be a PGPR by partial 16S rDNA sequencing. Biochar applied in our study was made from wheat straw and was used at three application levels (0 t.hm−2, 20.0 t hm−2, 40 t.hm−2). The following treatments were evaluated: (1) no PGPR and no biochar applied (M0B0), (2) 5 × 1010 cfu/mL PGPR (MB0), (3) 20.0 t.hm−2 biochar (B20), (4) 5 × 1010 cfu/mL PGPR plus 20.0 t.hm−2 biochar (MB20), (5) 5 × 1010 cfu/mL PGPR plus 40.0 t.hm−2 biochar (MB40). In general, separate application of PGPR and biochar may increase soil urease activity, total nitrogen (TN), and total potassium (TK) concentrations, and co-application of PGPR and biochar may increase soil sucrase activity, electrical conductivity (EC), and TK concentration, indicating that the manner of biochar and PGPR application had a significant influence on soil physicochemical properties and enzyme activities except for TK concentration. Redundancy analysis (RDA) showed that soil NO3−-N, NH4+-N, TK, TP, and SWC were more closely related to soil enzyme activities than other soil physicochemical properties under our experimental conditions.

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.

Scaphanocephalus-associated dermatitis as the basis for black spot disease in Acanthuridae of St. Kitts, West Indies.

Acanthurus spp. of St. Kitts and other Caribbean islands, including ocean surgeonfish A. bahianus, doctorfish A. chirurgus, and blue tang A. coeruleus, frequently show multifocal cutaneous pigmentation. Initial reports from the Leeward Antilles raised suspicion of a parasitic etiology. The aim of this study was to quantify the prevalence of the disease in St. Kitts' Acanthuridae and describe its pathology and etiology. Visual surveys demonstrated consistently high adjusted mean prevalence at 3 shallow reefs in St. Kitts in 2017 (38.9%, 95% CI: 33.8-43.9) and 2018 (51.5%; 95% CI: 46.2-56.9). There were no differences in prevalence across species or reefs, but juvenile fish were less commonly affected than adults. A total of 29 dermatopathy-affected acanthurids were sampled by spearfishing for comprehensive postmortem examination. Digenean metacercariae were dissected from <1 mm cysts within pigmented lesions. Using partial 28S rDNA sequence data they were classified as Family Heterophyidae, members of which are commonly implicated in black spot disease of other fishes. Morphological features of the parasite were most typical of Scaphanocephalus spp. (Creplin, 1842), and 2 genetic profiles were obtained suggesting more than 1 digenean species. Histologically, pigmented lesions had mild chronic perivascular dermatitis and increased melanophores and melanin density, often centered on encysted digenean metacercariae. In 1 affected A. chirurgus, similar metacercariae were histologically identified in skeletal and cardiac muscle. Further research is needed to clarify impact on host fitness, establish the number of heterophyid digenean species that cause black spots on Caribbean fishes and to determine the intermediate and definitive host species.

Identification, Classification and Screening for γ-Amino-butyric Acid Production in Lactic Acid Bacteria from Cambodian Fermented Foods.

Screening for various types of lactic acid bacteria (LAB) that form the biological agent γ-amino-butyric acid (GABA) is important to produce different kinds of GABA-containing fermented foods. So far, no GABA-producing LAB have been reported from Cambodian fermented foods. Most small-scale fermentations and even some industrial processes in this country still rely on indigenous LAB. The application of GABA-producing autochthonous starters would allow the production of Cambodian fermented foods with an additional nutritional value that meet the population’s dietary habits and that are also more attractive for the international food market. Matrix-assisted laser desorption/ionizing time-of-flight mass spectrometry (MALDI-TOF MS) and partial 16S rDNA sequencing were used to identify 68 LAB isolates from Cambodian fermented foods. These isolates were classified and grouped with (GTG)5 rep-PCR, resulting in 50 strains. Subsequently, all strains were investigated for their ability to produce GABA by thin layer chromatography. GABA-positive strains were further analyzed by the GABase assay. Of the six GABA-positive LAB strains—one Lactobacillus futsaii, two Lactobacillus namurensis, and three Lactobacillus plantarum strains—two Lactobacillus plantarum strains produced high amounts of GABA (20.34 mM, 16.47 mM). These strains should be further investigated for their potential application as GABA-producing starter cultures in the food applications.

Zinc biosorption, biochemical and molecular characterization of plant growth-promoting zinc-tolerant bacteria.

Zinc plays a key role in plant nutrition at low levels; however, at higher concentrations Zn ions can be highly phytotoxic and plant growth-promoting rhizobacteria can be used to reduce such metal toxicity. In the present investigation we had reported the zinc biosorption and molecular characterization of plant growth-promoting zinc-tolerant bacteria. Initially, thirty bacteria having zinc solubilizing ability were screened for MIC against zinc ion and displayed high value of MIC ranging from 2.5 to 62.5mM. Biochemically, all the 30 isolates showed significant difference in the 6 biochemical tests performed. The molecular diversity studies based on the repetitive DNA PCR viz, REP, ERIC and BOX elements showed significant genetic diversity among these 30 zinc-tolerant bacteria. These ZTB strains also showed multiple PGP activities and all ZTB strains were found positive for production of IAA, GA3 and ammonia, whereas 24 were found positive for ACC deaminase activity, 8 showed siderophore production and 9 ZTB isolates were positive for HCN production. Out of 30 isolates, 24 showed phosphorus solubilization activity, 30 showed potash solubilization, 15 showed silica solubilization and 27 showed phytase production activities. All the 30 ZTB stains showed zinc solubilization up to 0.25% insoluble ZnO in the medium, whereas at 2% ZnO in MSM only 12 isolates showed solubilization which were further selected for zinc biosorption and pot studies. The heavy metal removal studies revealed that ZTB stains were able to remove zinc ions effectively from the medium efficiently and the highest zinc biosorption (< 90%) was recorded with the bacterial strain Z-15. Further, the inoculation of ZTB strains under zinc stress conditions (pot containing 1000mg/kg Zn) resulted in significant increase of shoot length, root length and total chlorophyll content in maize seedlings compared with the uninoculated control. The partial 16S rDNA sequence of the potential ZTB isolates viz. Z-15, Z-24, Z-28 and Z-29 revealed their identity as Serratia sp. The ability of these zinc-tolerant bacteria to tolerate the toxic level of zinc may serve as suitable candidates for developing microbial formulations for the growth of crop plants in Zn-contaminated areas.

Systematic revision of the Tubifera casparyi–T. dictyoderma complex: Resurrection of the genus Siphoptychium and introduction of the new genus Thecotubifera

ABSTRACTThe genus Siphoptychium is resurrected on the basis of comparative morphology and phylogeny of partial nuc 18S rDNA (18S) and translation elongation factor 1-alpha (EF1A) nucleotide sequences. The genus is characterized by the firm upper surface of the pseudoaethalium, accreted but easily separable sporothecae, a tubular or fibrous columella, and spores with a reticulate ornamentation consisting of 7–9 meshes across the diameter. In addition to the currently known single species S. casparyi (= Tubifera casparyi), two new members of Siphoptychium are described: S. violaceum from coniferous forests of Europe, east Asia, and southeast Asia, and S. reticulatum from temperate and subarctic regions of North America and alpine regions of Europe. A second genus, Thecotubifera, is described to accommodate Tubifera dictyoderma. The fruiting body of this species is transitional between a pseudoaethalium and a true aethalium. It is covered by a contiguous membranous cortex formed by the fused tips of the sporothecae, a feature typical for aethalia. However, the inner portions of sporothecae remain discernible, a feature more typical for pseudoaethalia. Columellae of Th. dictyoderma are formed by perforated plates, and the spores have a reticulate ornamentation consisting of 2–5 meshes across the diameter. For Th. dictyoderma, we could confirm records only for tropical regions and Japan, whereas all studied European specimens, including those mentioned in current monographs, represent species of Siphoptychium.

The intermediate hosts of Wardium cirrosa (Krabbe, 1869) Spassky, 1961 (Cestoda, Cyclophyllidea, Aploparaksidae) in Ukraine.

The metacestodes of aploparaksid cestode Wardium cirrosa Krabbe, 1869 parasitic in gulls were found in polychaetes of the family Nereidae collected off the Black Sea coast, Ukraine. Two species of polychaetes, Hediste diversicolor (prevalence 5.3%; intensity 1-3 specimens) and Neanthes succinea (prevalence 9.9%; intensity 1-39 specimens), were infected with cysticercoids that were observed either individually or in accumulations. The preliminary identification of the material based on morphological characteristics was later confirmed by experimental infection of the definitive host, Larus cachinnans (Charadriiformes: Laridae) with metacestodes, and by the identity of the partial 28S rDNA sequences of cysticercoids and experimentally obtained adults. Although previous studies suggested freshwater leeches as the intermediate host for W. cirrosa, our study provides the evidence for marine polychaetes to serve as intermediate hosts. This study is the first to present the morphological characteristics of metacestodes of W. cirrosa in addition to molecular data for this species, as well as reporting the possibility of several cysticercoids developing from a single oncosphere. Morphology of the adult specimens obtained in the experiment was compared with adults of W. cirrosa previously collected from L. cachinnans in Ukraine. The results of our study suggest that further research focused on the elucidation of the life cycles of cestodes within the genus Wardium should consider marine invertebrates as potential intermediate hosts.

First record of natural Baylisascaris transfuga (Ascaridoidea, Nematoda) infection in wild rodents.

The intestinal parasitic nematode, Baylisascaris transfuga, was recorded in wild rodents for the first time. Representatives of four murid species (15 Myodes rufocanus, 10 M. rutilus, 3 M. glareolus and 27 Microtus oeconomus) were collected in the White Sea coastal habitats in the south of the Kola Peninsula, Russia in July 2015 and examined for parasites. Encapsulated nematode larvae were detected in the mesentery and the large intestine wall of one grey-sided vole (M. rufocanus) and one tundra vole (M. oeconomus). Based on morphology, the larvae were identified as belonging to the genus Baylisascaris Sprent 1968. The partial 18S rDNA sequence of the larvae from the voles was obtained and fully corresponded to the sequence of Baylisascaris transfuga in the NCBI GenBank. The ITS rDNA and CoxI mtDNA sequences these larvae were also similar to the respective B. transfuga sequences in GenBank. The presence of B. transfuga in wild rodents suggests that rodents can participate in the B. transfuga life cycle.

Redescription of Acanthogyrus (Acanthosentis) maroccanus (Dollfus, 1951) (Acanthocephala: Quadrigyridae), a parasite of the Algerian barb Luciobarbus callensis (Valenciennes) (Cyprinidae) in Algeria, and first molecular data.

Acanthogyrus (Acanthosentis) maroccanus (Dollfus, 1951), an insufficiently described quadrigyrid acanthocephalan of cyprinid fishes from Northwest Africa, is redescribed based on recently collected specimens from the Algerian barb Luciobarbus callensis (Valenciennes) in Algeria. Newly observed morphological features for A. (A.) maroccanus include the arrangement of proboscis hooks (not in regular circles), the male reproductive structures extending into the copulatory bursa and the presence of a para-receptacle structure and vaginal sleeve. The mechanism of copulation of this acanthocephalan is described based on several copulating pairs. The phylogenetic position of A. (A.) maroccanus within Eoacanthocephala was assessed based on partial 28S rDNA sequences. Maximum likelihood and Bayesian inference analyses placed A. (A.) maroccanus in a clade with Palliolisentis (Demidueterospinus) ophiocephalus (Thapar, 1931), both species included in the Quadrigyridae, the only family within the Gyracanthocephala.

Isolation and Identification of Pesticides Degrading Bacteria from Farmland Soil

Pesticides are recognized to be the threat to the environment and associated with a wide range of serious diseases including respiratory diseases, cancer and even birth defects. In this study, six-different bacterial strains capable of degrading Carbofuran, Emamectin Benzoate and Thiamethoxam were isolated from eight different soil samples. The isolates were characterized by using different conventional and molecular methods. The strains were identified molecularly into different genotypes using amplified ribosomal DNA restriction analysis (ARDRA) and partial sequencing of 16S rDNA. The ARDRA pattern clustered them into 3 groups. Among the isolates three were identified as Achromobacter spp. and one as Diaphorobacter sp. by biochemical tests. It was further confirmed by the partial 16S rDNA sequencing. The two identified potential bacteria can be used for biodegradation of different pesticides which can have a significant environmental impact in soil farm.&#x0D; Bangladesh J Microbiol, Volume 35 Number 2 December 2018, pp 90-94