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1.
Neotrop Entomol ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38918340

ABSTRACT

Mosquitoes (Diptera: Culicidae) pose a significant threat to public health worldwide, especially in tropical and subtropical regions, where they act as primary vectors in transmission of infectious agents. In Peru, 182 culicid species have been identified and several species of the genus Culex are known to transmit arboviruses. However, knowledge of mosquito diversity and distribution remains limited, with many studies focusing on specific regions only. Here, we describe a new morphological variation of Cx. (Culex) coronator Dyar and Knab, 1906, and report the presence of Culex (Carrollia) bonnei Dyar, 1921 in the central region of Peru, Huanuco. Specimens were obtained through larvae collections and identified through morphologic characterization, including dissection of male genitalia, and molecular analyses. In total, 17 mosquitoes were analyzed, and the genitalia of the male specimens allowed the identification of Cx. coronator and Cx. bonnei. Partial sequences of the CoxI gene corresponding to these two species were obtained (N = 10). Phylogenetic analysis revealed that the sequences of Cx. coronator grouped in a monophyletic clade with sequences ascribed to other species corresponding to the subgenus Carrollia, while Cx. bonnei specimens formed a monophyletic clade with homologous sequences from GenBank. This study underscores the importance of continued efforts to study the diversity and distribution of mosquitoes in Peru, including their potential role as vectors of human pathogens, to underpin effective disease control and prevention strategies, highlighting the importance of a complemented morphological and molecular analysis.

2.
J Phycol ; 60(1): 116-132, 2024 02.
Article in English | MEDLINE | ID: mdl-38289653

ABSTRACT

Over the last 2 decades, routine collections in the Hawaiian Archipelago have expanded to mesophotic reefs, leading to the discovery of a new red algal genus and species, here described as Anunuuluaehu liula gen. et sp. nov. This study provides a detailed genus and species description and characterizes chloroplast and mitochondrial organellar genomes. The new genus, Anunuuluaehu, shares many characteristics with the family Phyllophoraceae and shows close similarities to Archestennogramma and Stenogramma, including habit morphology, nemathecia forming proliferations at the outer cortex with terminal chains of tetrasporangia, and carposporophytes with multi-layered pericarps. The single species in this genus exhibits distinctive features within the Phyllophoraceae: the presence of single-layer construction of large medullary cells and the development of long, tubular gonimoblastic filaments. Multi-gene phylogenetic analyses confirmed it as a unique, monophyletic lineage within the family. Cis-splicing genes, interrupted by intron-encoded proteins within group II introns, are present in both the chloroplast and mitochondrial genomes of A. liula. Notably, a specific region of the coxI group II intron exhibits similarity to fungal introns. Anunuuluaehu liula is presumed to be endemic to the Hawaiian Archipelago and thus far is known to live solely at mesophotic depths from Holaniku to Kaho'olawe ranging from 54 to 201 m, which is the deepest collection record of any representative in the family. Overall, this study enhances our understanding of the genomic and taxonomic complexities of red algae in mesophotic habitats, emphasizing the significance of continued research in this area to uncover further insights into evolutionary processes and biogeographic patterns.


Subject(s)
Rhodophyta , Phylogeny , Hawaii , Rhodophyta/genetics , Biological Evolution , Genomics
3.
Parasit Vectors ; 16(1): 319, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37684698

ABSTRACT

BACKGROUND: Aedes aegypti and Ae. albopictus are important human arbovirus vectors that can spread arboviral diseases such as yellow fever, dengue, chikungunya and Zika. These two mosquito species coexist on Hainan Island and the Leizhou Peninsula in China. Over the past 40 years, the distribution of Ae. albopictus in these areas has gradually expanded, while Ae. aegypti has declined sharply. Monitoring their genetic diversity and diffusion could help to explain the genetic influence behind this phenomenon and became key to controlling the epidemic of arboviruses. METHODS: To better understand the genetic diversity and differentiation of these two mosquitoes, the possible cohabiting areas on Hainan Island and the Leizhou Peninsula were searched between July and October 2021, and five populations were collected. Respectively nine and 11 microsatellite loci were used for population genetic analysis of Ae. aegypti and Ae. albopictus. In addition, the mitochondrial coxI gene was also selected for analysis of both mosquito species. RESULTS: The results showed that the mean diversity index (PIC and SI values) of Ae. albopictus (mean PIC = 0.754 and SI = 1.698) was higher than that of Ae. aegypti (mean PIC = 0.624 and SI = 1.264). The same results were also observed for the coxI gene: the genetic diversity of all populations of Ae. albopictus was higher than that of Ae. aegypti (total H = 45 and Hd = 0.89958 vs. total H = 23 and Hd = 0.76495, respectively). UPGMA dendrogram, DAPC and STRUCTURE analyses showed that Ae. aegypti populations were divided into three clusters and Ae. albopictus populations into two. The Mantel test indicated a significant positive correlation between genetic distance and geographic distance for the Ae. aegypti populations (R2 = 0.0611, P = 0.001), but the correlation was not significant for Ae. albopictus populations (R2 = 0.0011, P = 0.250). CONCLUSIONS: The population genetic diversity of Ae. albopictus in Hainan Island and the Leizhou Peninsula was higher than that of Ae. aegypti. In terms of future vector control, the most important and effective measure was to control the spread of Ae. albopictus and monitor the population genetic dynamics of Ae. aegypti on Hainan Island and the Leizhou Peninsula, which could theoretically support the further elimination of Ae. aegypti in China.


Subject(s)
Aedes , Chikungunya Fever , Zika Virus Infection , Zika Virus , Humans , Animals , Aedes/genetics , Mosquito Vectors/genetics , China , Genetic Variation
4.
Iran J Public Health ; 52(4): 818-828, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37551192

ABSTRACT

Background: The liver flukes of the Fasciola species and Dicrocoelium spp. are recognised as parasites of domestic and wild herbivores. Both species of F. hepatica and F. gigantica as well as D. dendriticum are distributed in Iran. The present study aimed to identify Fasciola spp. and Dicrocoelium spp. using mitochondrial Cox1 (cytochrome c oxidase I) gene by HRM method. Methods: Totally, thirty infected liver specimens were collected from the sheep (n:23) and cattle (n:7) at the abattoirs of Qazvin Province, northwest Iran in 2022. DNA extraction and PCR amplification of Cox1 gene were conducted by HRM technique. DnaSP v.5.0 was used for compression of diversity indices of ribosomal 28S rDNA and mitochondrial Cox1 markers of Dicrocoelium spp. The taxonomic status of Dicrocoelium spp. was performed by sequencing and phylogenetic analysis. Results: Overall, 26 and 4 isolates were identified as F. hepatica and F. gigantica, respectively. D. dendriticum was the sole infecting species of Dicrocoelium revealed by HRM analysis. Genomic analysis showed a moderate (28S rDNA genes: 0.600±0.215) to high (Cox1: 0.733±0.155) haplotype diversity for D. dendriticum. Conclusion: The parasite-dependent mitochondrial gene (Cox1) could identify a higher genetic diversity of D. dendriticum compared to nuclear 28S rDNA gene. HRM technique in the present study found to be a reliable technique for identification and genetic diversity of liver flukes but more comprehensive and in-depth studies in different parts of the country are needed.

5.
Parasitology ; 150(9): 842-851, 2023 08.
Article in English | MEDLINE | ID: mdl-37415562

ABSTRACT

In recent years, parasite conservation has become a globally significant issue. Because of this, there is a need for standardized methods for inferring population status and possible cryptic diversity. However, given the lack of molecular data for some groups, it is challenging to establish procedures for genetic diversity estimation. Therefore, universal tools, such as double-digest restriction-site-associated DNA sequencing (ddRADseq), could be useful when conducting conservation genetic studies on rarely studied parasites. Here, we generated a ddRADseq dataset that includes all 3 described Taiwanese horsehair worms (Phylum: Nematomorpha), possibly one of the most understudied animal groups. Additionally, we produced data for a fragment of the cytochrome c oxidase subunit I (COXI) for the said species. We used the COXI dataset in combination with previously published sequences of the same locus for inferring the effective population size (Ne) trends and possible population genetic structure.We found that a larger and geographically broader sample size combined with more sequenced loci resulted in a better estimation of changes in Ne. We were able to detect demographic changes associated with Pleistocene events in all the species. Furthermore, the ddRADseq dataset for Chordodes formosanus did not reveal a genetic structure based on geography, implying a great dispersal ability, possibly due to its hosts. We showed that different molecular tools can be used to reveal genetic structure and demographic history at different historical times and geographical scales, which can help with conservation genetic studies in rarely studied parasites.


Subject(s)
Helminths , Parasites , Animals , Helminths/genetics , Base Sequence , Sequence Analysis, DNA , Genetics, Population , Genetic Variation
6.
Heliyon ; 9(2): e13255, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36846682

ABSTRACT

Filariasis is classified as a vector-borne zoonotic disease caused by several filarial nematodes. The disease is widely distributed in tropical and subtropical regions. Understanding the relationship between mosquito vectors, filarial parasites, and vertebrate hosts is therefore essential for determining the probability of disease transmission and, correspondingly, developing effective strategies for prevention and control of diseases. In this study, we aimed to investigate the infection of zoonotic filarial nematodes in field-caught mosquitoes, observe the potential vectors of filaria parasites in Thailand using a molecular-based survey, conduct a study of host-parasite relationship, and propose possible coevolution of the parasites and their hosts. Mosquitoes were collected around cattle farms in Bangkok, Nakhon Si Thammarat, Ratchaburi, and Lampang provinces from May to December 2021 using a CDC Backpack aspirator for 20-30 minutes in each area (intra-, peri-, and wild environment). All mosquitoes were identified and morphologically dissected to demonstrate the live larvae of the filarial nematode. Furthermore, all samples were tested for filarial infections using PCR and sequencing. A total of 1,273 adult female mosquitoes consisted of five species: 37.78% Culex quinquefasciatus, 22.47% Armigeres subalbatus, 4.71% Cx. tritaeniorhynchus, 19.72% Anopheles peditaeniatus, and 15.32% An. dirus. Larvae of Brugia pahangi and Setaria labiatopapillosa were found in Ar. subalbatus and An. dirus mosquitoes, respectively. All mosquito samples were processed by PCR of ITS1 and COXI genes for filaria nematode species identification. Both genes showed that B. pahangi was found in four mosquitoes of Ar. subalbatus from Nakhon Si Thammarat, S. digitata was detected in three samples of An. peditaeniatus from Lampang, and S. labiatopapillosa was detected in one of An. dirus from Ratchaburi. However, filarial nematodes were not found in all Culex species. This study infers that this is the first data regarding the circulation of Setaria parasites in Anopheles spp. from Thailand. The phylogenetic trees of the hosts and parasites are congruent. Moreover, the data could be used to develop more effective prevention and control strategies for zoonotic filarial nematodes before they spread in Thailand.

7.
Parasitol Res ; 122(3): 881-887, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36640182

ABSTRACT

Nematodes of the genus Dictyocaulus are the causative agents of parasitic bronchitis and pneumonia in several domestic and wild ungulates. Various species have been described in wild cervids, as the case of Dictyocaulus cervi in red deer, recently described as a separate species from Dictyocaulus eckerti. In Italy, information on dictyocaulosis in wildlife is limited and often outdated. In this work, 250 red deer were examined for the presence of Dictyocaulus spp. in two areas of the Italian Alps (n = 104 from Valle d'Aosta, n = 146 from Stelvio National Park), and the retrieved lungworms were molecularly characterized. Lungworms were identified in 23 and 32 animals from Valle d'Aosta and Stelvio National Park, respectively. The nematodes, morphologically identified as D. cervi, were characterized molecularly (18S rDNA, ITS2, and coxI). Consistently, almost all specimens were found to be phylogenetically related to D. cervi. Three individuals, detected from both study sites and assigned to an undescribed Dictyocaulus sp., clustered with Dictyocaulus specimens isolated from red deer and fallow deer in previous studies. Within each of D. cervi and the undescribed Dictyocaulus sp., the newly isolated nematodes phylogenetically clustered based on their geographical origin. This study revealed the presence of D. cervi in Italian red deer, and an undetermined Dictyocaulus sp. that should be more deeply investigated. The results suggest that further analyses should be focused on population genetics of cervids and their lungworms to assess how they evolved, or co-evolved, throughout time and space and to assess the potential of transmission towards farmed animals.


Subject(s)
Deer , Dictyocaulus Infections , Nematoda , Animals , Dictyocaulus/genetics , Animals, Wild/parasitology , Deer/parasitology , Dictyocaulus Infections/epidemiology , Dictyocaulus Infections/parasitology
8.
Acta Parasitol ; 67(4): 1626-1633, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36074238

ABSTRACT

PURPOSE: Tape worm infection is common among sheep at SRRC, Mannavanur, Palani hills, Tamil Nadu, India. The aim of the present study is to find out the cestode species infecting the sheep being maintained at SRRC, Mannavanur, by means of molecular method. METHODS: During the second week of June 2021, the hogget flock of sheep (comprising both Bharat Merino and Avikalin sheep breeds) was drenched on empty stomach with commercial preparation of anthelmintic drug containing Niclosamide plus Albendazole, as per the standard dose specified by the manufacturer (Niclozole™: each 5 ml contains 500 mg of Niclosamide and 150 mg of Albendazole: dose for sheep-10 ml/15 kg body weight). The tapeworms expelled in dung by the drug-treated sheep were collected, washed in PBS (pH 7.2), and fixed in between two glass slides using 10% formalin. Furthermore, cytochrome c oxidase subunit I (Cox-I) gene-based PCR was carried out. Only partial sequence (1593 bp) of Cox-I gene of Moniezia expansa from Sheep at SRRC, Mannavanur, Tamil Nadu, India was obtained by PCR. The PCR amplified fragment was cloned into pGEM-T vector and the recombinant plasmid was sequenced. The obtained nucleotide sequences of Cox-I gene of the M. expansa from Indian sheep were analysed with that of 27 more cestode species from different mammalian species (available in GenBank) using bioinformatics tools. RESULTS: The species of the tapeworm was identified as Moniezia species by the Department of Veterinary Parasitology, VC& RI, Orathanadu, TANUVAS by the standard Acidic alum carmine staining method. Due to the ambiguity in the conventional method, Cox-I gene-based PCR and subsequent gene sequencing protocols were used for the identification of the species of cestode infecting sheep at SRRC, Mannavanur, and it was confirmed as M. expansa upon BLAST analysis. Moniezia expansa from SRRC, Mannavanur is having 100% sequence identity at nucleotide level with that of M. expansa from Sengal/Ethiopia. M. benedeni shared 87-88% nucleotide identity with Indian M. expansa. With taenids, the share of percent nucleotide identity of Indian M. expansa ranged from 79 to 81%. M. expansa from Indian sheep was clustering with other anaplocephalids from various mammalian species in the analysis of phylogenetic tree based on Cox-I nucleotide sequences. CONCLUSION: From the present study, it is concluded that M. expansa is the anoplocephalid cestode infecting the sheep at Mannavanur, Tamil Nadu, India. To our knowledge, this is the first report on partial nucleotide sequences of Cox-I gene of M. expansa from Sheep of Indian peninsula. An investigation on the involvement of oribatid mites as the vector in the transmission of M. expansa among sheep at SRRC, Mannavanur needs to be carried out.


Subject(s)
Albendazole , Cestoda , Sheep , Animals , Phylogeny , Niclosamide , India/epidemiology , Cestoda/genetics , Nucleotides , Mammals
9.
Parasit Vectors ; 15(1): 270, 2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35906628

ABSTRACT

We read with great interest the article by Hendershot et al. (Parasit Vectors 14:473, 2021). The authors compared a PCR method for detecting Plasmodium vivax's mitochondrial (mt) cytochrome oxidase I (COX-I) gene with the current "gold standard" circumsporozoite (CSP) ELISA for detecting circumsporozoite protein for identification of different life stages of Plasmodium vivax during development within Anopheles arabiensis. We found that Cohen's kappa value for measuring the agreement between mt COX-I PCR and CSP ELISA was questionable. In addition, we recommend a more appropriate statistical method in this article.In short, any scientific conclusion requires support by the reasonable application of methodological and statistical methods.


Subject(s)
Anopheles , Plasmodium , Animals , Enzyme-Linked Immunosorbent Assay/methods , Plasmodium/genetics , Plasmodium falciparum/genetics , Plasmodium vivax/genetics , Protozoan Proteins/genetics
10.
J Vector Borne Dis ; 59(1): 22-28, 2022.
Article in English | MEDLINE | ID: mdl-35708400

ABSTRACT

BACKGROUND & OBJECTIVES: Accurate mosquito species identification is the basis of entomological surveys and effective vector control. Mosquito identification is either done morphologically using diagnostic features mentioned in taxonomic keys or by molecular methods using cytochrome oxidase subunit 1 (coxI) and Internal transcribed spacer 2 (ITS2). METHODS: We performed a larval survey for Aedes mosquitoes from eight different geographical regions in Tamil Nadu, India. The mosquitoes collected during the survey were characterized using both morphological and molecular markers. RESULTS: During an entomological survey from eight different geographical regions in Southern India, a morphological variety named Aedes aegypti var. luciensis was observed. The variant mosquitoes were characterized using both morphological and molecular markers. The variant mosquitoes differed only in the dark scaling of 5th segment of hind-tarsi. Around one third to two third of the 5th segment in variant mosquitoes was dark which has been described as white in identification keys. No other significant difference was observed in adults or immature stages. The variation was heritable and coexisting in the field with the type form mosquitoes. Comparison of the genetic profile of coxI and ITS2 were similar in variant and the type form indicating both of them to be conspecific. INTERPRETATION & CONCLUSION: The morphological variant mosquitoes were found genetically similar to the Ae. aegypti type form. However, considering its high prevalence and coexistence with Ae. aegypti type form in different geographical regions, detailed studies on bionomics, ecology, genetics, behavior as well as its plausible role in disease transmission are warranted.


Subject(s)
Aedes , Aedes/genetics , Animals , Entomology , India , Larva/genetics , Mosquito Vectors/genetics
11.
Paediatr Child Health ; 27(1): 63-64, 2022 Mar.
Article in English, English | MEDLINE | ID: mdl-35273674

ABSTRACT

Management of the patent ductus arteriosus (PDA) is one of the most contentious topics in the care of preterm infants. PDA management can be broadly divided into prophylactic and symptomatic therapy. Prophylaxis with intravenous indomethacin in extremely low birth weight infants may reduce severe intraventricular hemorrhage. Echocardiography should be routinely used to confirm the presence of a PDA before considering symptomatic therapy. A symptomatic PDA can be managed conservatively, using pharmacotherapy or with procedural closure. Ibuprofen should be considered as the pharmacotherapy of choice for a symptomatic PDA. High-dose ibuprofen may be preferable, especially for preterm infants beyond the first 3 to 5 days of age. If pharmacotherapy fails (after two courses) or is contraindicated, procedural closure may be considered for infants with a persistent PDA with significant clinical symptoms in addition to echocardiographic signs of a large PDA shunt volume and pulmonary over-circulation.

12.
Parasit Vectors ; 14(1): 473, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34526109

ABSTRACT

BACKGROUND: In characterizing malaria epidemiology, measuring mosquito infectiousness informs the entomological inoculation rate, an important metric of malaria transmission. PCR-based methods have been touted as more sensitive than the current "gold-standard" circumsporozoite (CSP) ELISA. Wider application of PCR-based methods has been limited by lack of specificity for the infectious sporozoite stage. We compared a PCR method for detecting the parasite's mitochondrial (mt) cytochrome oxidase I (COX-I) gene with ELISA for detecting circumsporozoite protein for identification of different life stages of the parasite during development within a mosquito. METHODS: A PCR-based method targeting the Plasmodium mt COX-I gene was compared with the CSP ELISA method to assess infectivity in Anopheles arabiensis colony mosquitoes fed on blood from patients infected with Plasmodium vivax. Mosquitoes were tested at six post-infection time points (days 0.5, 1, 6, 9, 12, 15). The head and thorax and the abdomen for each specimen were tested separately with each method. Agreement between methods at each infection stage was measured using Cohen's kappa measure of test association. RESULTS: Infection status of mosquitoes was assessed in approximately 90 head/thorax and 90 abdomen segments at each time point; in total, 538 head/thorax and 534 abdomen segments were tested. In mosquitoes bisected after 0.5, 1, and 6 days post-infection (dpi), the mt COX-I PCR detected Plasmodium DNA in both the abdomen (88, 78, and 67%, respectively) and head/thorax segments (69, 60, and 44%, respectively), whilst CSP ELISA detected sporozoites in only one abdomen on day 6 post-infection. PCR was also more sensitive than ELISA for detection of Plasmodium in mosquitoes bisected after 9, 12, and 15 dpi in both the head and thorax and abdomen. There was fair agreement between methods for time points 9-15 dpi (κ = 0.312, 95% CI: 0.230-0.394). CONCLUSIONS: The mt COX-I PCR is a highly sensitive, robust method for detecting Plasmodium DNA in mosquitoes, but its limited Plasmodium life-stage specificity cannot be overcome by bisection of the head and thorax from the abdomen prior to PCR. Thus, the mt COX-I PCR is a poor candidate for identifying infectious mosquitoes.


Subject(s)
Anopheles/parasitology , Enzyme-Linked Immunosorbent Assay/standards , Life Cycle Stages/genetics , Plasmodium vivax/genetics , Polymerase Chain Reaction/standards , Sporozoites/genetics , Animals , Enzyme-Linked Immunosorbent Assay/methods , Female , Plasmodium vivax/immunology , Polymerase Chain Reaction/methods , Sporozoites/immunology
13.
Plants (Basel) ; 10(4)2021 Mar 31.
Article in English | MEDLINE | ID: mdl-33807482

ABSTRACT

Pratylenchus penetrans is an economically important root-lesion nematode species that affects agronomic and ornamental plants. Understanding its diversity is of paramount importance to develop effective control and management strategies. This study aimed to characterize the morphological and genetic diversity among seven European isolates. An isolate from the USA was included in the molecular analyses for comparative purposes. Morphometrics of the European P. penetrans isolates generally were within the range of the original descriptions for this species. However, multiple morphometric characteristics, including body length, maximum body width, tail length and length of the post-vulval uterine sac showed discrepancies when compared to other populations. Nucleotide sequence-based analyses revealed a high level of intraspecific diversity among the isolates. We observed no correlation between D2-D3 rDNA- and COXI-based phylogenetic similarities and geographic origin. Our phylogenetic analyses including selected GenBank sequences also suggest that the controversy surrounding the distinction between P. penetrans and P. fallax remains.

14.
Phytopathology ; 111(4): 720-730, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32865467

ABSTRACT

Reniform nematodes of the genus Rotylenchulus are semi-endoparasites of numerous herbaceous and woody plant species roots and occur largely in regions with temperate, subtropical, and tropical climates. In this study, we provide new records of the nematode Rotylenchulus macrosoma in eight European countries (Czech Republic, France, Germany, Hungary, Italy, Romania, Serbia, and Portugal), in addition to the six Mediterranean countries (Greece, Israel, Jordan, Spain, Syria, and Turkey) where the nematode was previously reported. Four new host species (corn, pea, wheat, and an almond-peach hybrid rootstock) are added to the recorded host species (bean, chickpea, hazelnut, peanut, soybean, and wild and cultivated olive). Molecular analyses based on the cytochrome c oxidase subunit coxI and D2-D3 segments of 28S RNA markers showed high diversity and pronounced genetic structure among populations of Rotylenchulus macrosoma. However, the complexity of phylogeographic patterns in plant-parasitic nematodes may be related to the intrinsic heterogeneity in the distribution of soil organisms, a rare occurrence of a species, or the potential human impact associated with agricultural practices.


Subject(s)
Nematoda , Plant Diseases , Animals , Europe , France , Germany , Greece , Israel , Italy , Nematoda/genetics , Phylogeny , Spain , Turkey
15.
Plants (Basel) ; 9(12)2020 Nov 26.
Article in English | MEDLINE | ID: mdl-33255931

ABSTRACT

Dagger nematodes of the genus Xiphinema include a remarkable group of invertebrates of the phylum Nematoda comprising ectoparasitic animals of many wild and cultivated plants. Damage is caused by direct feeding on root cells and by vectoring nepoviruses that cause diseases on several crops. Precise identification of Xiphinema species is critical for launching appropriate control measures. We deciphered the cryptic diversity of the Xiphinema hispanum-species complex applying integrative taxonomical approaches that allowed us to verify a paradigmatic example of the morphostatic speciation and the description of a new species, Xiphinema malaka sp. nov. Detailed morphological, morphometrical, multivariate and genetic studies were carried out, and mitochondrial and nuclear haploweb analyses were used for species delimitation of this group. The new species belongs to morphospecies Group 5 from the Xiphinema nonamericanum-group species. D2-D3, ITS1, partial 18S, and partial coxI regions were used for inferring the phylogenetic relationships of X. malaka sp. nov. with other species within the genus Xiphinema. Molecular analyses showed a clear species differentiation not paralleled in morphology and morphometry, reflecting a clear morphostatic speciation. These results support the hypothesis that the biodiversity of dagger nematodes in southern Europe is greater than previously assumed.

16.
Zookeys ; 894: 1-17, 2019.
Article in English | MEDLINE | ID: mdl-31844406

ABSTRACT

Plant-parasitic nematodes of the genus Xiphinema Cobb, 1913 comprise a complex group of nematode species, some of which are important vectors of plant viruses. During a field survey to determine the soil health of an abandoned honeybush (Cyclopia genistoides) monoculture, a high density of the dagger nematode, Xiphinema oxycaudatum Lamberti & Bleve-Zacheo, 1979 (Nematoda, Dorylaimidae), was observed in soil around the roots of honeybush plants in an abandoned farmland at Bereaville, an old mission station in the Western Cape province of South Africa. Soil samples were taken from the rhizosphere of plants and nematodes were extracted from the soil using a modified extraction tray method. Specimen of the dagger nematodes were processed for scanning electron microscopy, morphological and molecular analysis. Molecular profiling of the nematode species was done in order to give an accurate diagnosis and to effectively discriminate the nematode from other species within the Xiphinema americanum group. Phylogenetic analysis based on the D2D3 expansion segment of the 28S gene supported a close relationship of species within the americanum group, however, the protein-coding cytochrome oxidase (coxI) of the mitochondrial gene provided a useful tool for distinguishing the nematode from other species within the group. This study represents the first report of X. oxycaudatum from South Africa.

17.
J Helminthol ; 94: e87, 2019 Sep 13.
Article in English | MEDLINE | ID: mdl-31514757

ABSTRACT

The supralittoral amphipod Traskorchestia ditmari (Derzhavin, 1923) was identified as the intermediate host for Antechiniella septentrionalis Ivanova, Dokuchaev & Spiridonov, 2019, a parasite of the tundra vole Microtus oeconomus and Skrjabinocerca sp. (both Spirurida: Acuariidae) in Magadan Oblast in north-eastern Russia. Joint infection by both larval spirurids was not observed. The infective stage of A. septentrionalis was the encysted larvae, while larvae of Skrjabinocerca sp. were free in the amphipod's coelom. The identity of A. septentrionalis was confirmed using cox1 mtDNA gene analysis, performed on adult stages from a tundra vole and on larvae from amphipods. Possible transmission routes of A. septentrionalis are discussed.


Subject(s)
Amphipoda/parasitology , Arvicolinae/parasitology , Spirurida Infections/veterinary , Spirurida/physiology , Animals , Female , Larva , Male , Russia , Spirurida/growth & development , Tundra
18.
Iran J Public Health ; 48(3): 501-507, 2019 Mar.
Article in English | MEDLINE | ID: mdl-31223578

ABSTRACT

BACKGROUND: Fasciolosis is a shared disease between humans and livestock caused by hepatic trematodes; Fasciola hepatica and F. gigantica. Differentiate between the two species of this genus is essential. High-Resolution Melting (HRM) Analysis represents a new approach to this issue. This method can be performed right after termination of Real-Time PCR. This technique has not been used for identification of adult F. hepatica and F. gigantica genotypes. The aim of this study was to determine Fasciola species by using HRM in isolates taken from Iran, respectively. METHODS: Ninety-three Fasciola spp. samples were collected from infected slaughtered animals in different regions of Iran, including North West (Ardebil Province) and South East (Zahedan Province) during 2016. Genomic DNA from the samples was extracted using a DNA extraction kit and then after Real-Time PCR amplification, HRM was done. RESULTS: Overall, 59 and 34 isolates were identified as F. hepatica and F. gigantica, respectively. The percentages of each species from animals were as follows: sheep (F. hepatica, 80.39% and F. gigantica, 19.61%), cattle (F. hepatica, 42.85% and F. gigantica, 57.15%). CONCLUSION: HRM technique developed in the present study is a powerful, rapid and sensitive technique for epidemiological survey and molecular identification between F. hepatica and F. gigantica.

19.
PeerJ ; 6: e4845, 2018.
Article in English | MEDLINE | ID: mdl-29915686

ABSTRACT

Nowadays DNA meta-barcoding is a powerful instrument capable of quickly discovering the biodiversity of an environmental sample by integrating the DNA barcoding approach with High Throughput Sequencing technologies. It mainly consists of the parallel reading of informative genomic fragment/s able to discriminate living entities. Although this approach has been widely studied, it still needs optimization in some necessary steps requested in its advanced accomplishment. A fundamental element concerns the standardization of bioinformatic analyses pipelines. The aim of the present study was to underline a number of critical parameters of laboratory material preparation and taxonomic assignment pipelines in DNA meta-barcoding experiments using the cytochrome oxidase subunit-I (coxI) barcode region, known as a suitable molecular marker for animal species identification. We compared nine taxonomic assignment pipelines, including a custom in-house method, based on Hidden Markov Models. Moreover, we evaluated the potential influence of universal primers amplification bias in qPCR, as well as the correlation between GC content with taxonomic assignment results. The pipelines were tested on a community of known terrestrial invertebrates collected by pitfall traps from a chestnut forest in Italy. Although the present analysis was not exhaustive and needs additional investigation, our results suggest some potential improvements in laboratory material preparation and the introduction of additional parameters in taxonomic assignment pipelines. These include the correct setup of OTU clustering threshold, the calibration of GC content affecting sequencing quality and taxonomic classification, as well as the evaluation of PCR primers amplification bias on the final biodiversity pattern. Thus, careful attention and further validation/optimization of the above-mentioned variables would be required in a DNA meta-barcoding experimental routine.

20.
J Phycol ; 54(3): 391-409, 2018 06.
Article in English | MEDLINE | ID: mdl-29574890

ABSTRACT

A multi-gene (SSU, LSU, psbA, and COI) molecular phylogeny of the family Corallinaceae (excluding the subfamilies Lithophylloideae and Corallinoideae) showed a paraphyletic grouping of six monophyletic clades. Pneophyllum and Spongites were reassessed and recircumscribed using DNA sequence data integrated with morpho-anatomical comparisons of type material and recently collected specimens. We propose Chamberlainoideae subfam. nov., including the type genus Chamberlainium gen. nov., with C. tumidum comb. nov. as the generitype, and Pneophyllum. Chamberlainium is established to include several taxa previously ascribed to Spongites, the generitype of which currently resides in Neogoniolithoideae. Additionally we propose two new genera, Dawsoniolithon gen. nov. (Metagoniolithoideae), with D. conicum comb. nov. as the generitype and Parvicellularium gen. nov. (subfamily incertae sedis), with P. leonardi sp. nov. as the generitype. Chamberlainoideae has no diagnostic morpho-anatomical features that enable one to assign specimens to it without DNA sequence data, and it is the first subfamily to possess both Type 1 (Chamberlainium) and Type 2 (Pneophyllum) tetra/bisporangial conceptacle roof development. Two characters distinguish Chamberlainium from Spongites: tetra/biasporangial conceptacle chamber diameter (<300 µm in Chamberlainium vs. >300 µm in Spongites) and tetra/bisporangial conceptacle roof thickness (<8 cells in Chamberlainium vs. >8 cells in Spongites). Two characters also distinguish Pneophyllum from Dawsoniolithon: tetra/bisporangial conceptacle roof thickness (<8 cells in Pneophyllum vs. >8 cells in Dawsoniolithon) and thallus construction (dimerous in Pneophyllum vs. monomerous in Dawsoniolithon).


Subject(s)
Phylogeny , Rhodophyta/classification , DNA, Algal/analysis , Indian Ocean , Pacific Ocean , Rhodophyta/genetics , Sequence Analysis, DNA
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