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1.
Parasitol Res ; 122(12): 2819-2833, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37749315

RESUMO

The elucidation of life-cycles of digeneans, with their successive larval stages, is facilitated by the use of molecular markers. Samples of sporocysts containing cercariae and metacercariae belonging to Monorchis Monticelli, 1893 were collected from naturally infected bivalves, Cerastoderma glaucum (Bruguière, 1789), and adult forms of Monorchis spp. were collected from sparid fishes of the genus Diplodus. All specimens were collected in the Gulf of Gabès, southern Tunisia. The identities of the examined molluscs and fishes were determined via molecular barcoding of their COI gene. Sequences of COI and ITS1 genes were also obtained for both larval and adult stages of collected parasite specimens. Genetic sequence data generated for the collected larval specimens only differed minimally from the sequence data of adults identified as Monorchis parvus; we attribute the difference to intraspecific variation. The morpho-anatomical study showed that the different stages of M. parvus collected from the Tunisian coasts had the same morphology as those reported in European waters with a lag in maturity and lower measurements. The species is recorded and molecularly characterised for the first time off the Tunisian coasts.


Assuntos
Bivalves , Perciformes , Trematódeos , Animais , Tunísia , Estágios do Ciclo de Vida , Peixes/parasitologia , Perciformes/parasitologia , Larva , Filogenia
2.
Parasitol Res ; 120(7): 2363-2377, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33974138

RESUMO

Many Pauciconfibula spp. have a long and complicated taxonomic history. The remaining unsolved taxonomic confusion in this genus is impelled by the host range and status of Pauciconfibula spp. from trachinid fishes: Pauciconfibula trachini and Pauciconfibula draconis, from Trachinus radiatus and Trachinus draco (Trachinidae), respectively. Pauciconfibula trachini was reported on Trachinus draco, type host of Pauciconfibula draconis suggesting thus a stenoxenic specificity for the former monogenean and the occurrence of two congeneric polyopisthocotyleans on a single host. Moreover, the validity of Pauciconfibula draconis was repeatedly questioned by several authors, unjustified synonymy between the two species was proposed, and the delimitations between the two species remained unsolved. Original descriptions were also incomplete and poorly illustrated. In this study, we provide a detailed illustrated redescription of both species based on newly collected specimens of Pauciconfibula trachini and Pauciconfibula draconis collected from their type hosts from off three Mediterranean localities: Algeria, Tunisia, and Italy. Integrative taxonomy using COI sequences was applied to resolve the delimitation between Pauciconfibula trachini and P. draconis. This study provides the first DNA barcoding for members of this genus.


Assuntos
Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Trematódeos/classificação , Infecções por Trematódeos/veterinária , Argélia , Animais , Código de Barras de DNA Taxonômico , Feminino , Brânquias/parasitologia , Itália , Masculino , Mar Mediterrâneo , Perciformes/classificação , Perciformes/genética , Filogenia , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/genética , Infecções por Trematódeos/parasitologia , Tunísia
3.
Development ; 144(7): 1187-1200, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28174250

RESUMO

To understand how the identity of an organ can be switched, we studied the transformation of lateral root primordia (LRP) into shoot meristems in Arabidopsis root segments. In this system, the cytokinin-induced conversion does not involve the formation of callus-like structures. Detailed analysis showed that the conversion sequence starts with a mitotic pause and is concomitant with the differential expression of regulators of root and shoot development. The conversion requires the presence of apical stem cells, and only LRP at stages VI or VII can be switched. It is engaged as soon as cell divisions resume because their position and orientation differ in the converting organ compared with the undisturbed emerging LRP. By alternating auxin and cytokinin treatments, we showed that the root and shoot organogenetic programs are remarkably plastic, as the status of the same plant stem cell niche can be reversed repeatedly within a set developmental window. Thus, the networks at play in the meristem of a root can morph in the span of a couple of cell division cycles into those of a shoot, and back, through transdifferentiation.


Assuntos
Arabidopsis/citologia , Arabidopsis/crescimento & desenvolvimento , Meristema/citologia , Nicho de Células-Tronco , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Divisão Celular/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Citocininas/farmacologia , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Meristema/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Plantas/metabolismo , Nicho de Células-Tronco/efeitos dos fármacos , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
4.
Mol Phylogenet Evol ; 142: 106660, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639524

RESUMO

For over a decade now, High Throughput sequencing (HTS) approaches have revolutionized phylogenetics, both in terms of data production and methodology. While transcriptomes and (reduced) genomes are increasingly used, generating and analyzing HTS datasets remain expensive, time consuming and complex for most non-model taxa. Indeed, a literature survey revealed that 74% of the molecular phylogenetics trees published in 2018 are based on data obtained through Sanger sequencing. In this context, our goal was to identify the strategy that would represent the best compromise among costs, time and robustness of the resulting tree. We sequenced and assembled 32 transcriptomes of the marine mollusk family Turridae, considered as a typical non-model animal taxon. From these data, we extracted the loci most commonly used in gastropod phylogenies (cox1, 12S, 16S, 28S, h3 and 18S), full mitogenomes, and a reduced nuclear transcriptome representation. With each dataset, we reconstructed phylogenies and compared their robustness and accuracy. We discuss the impact of missing data and the use of statistical tests, tree metrics, and supertree and supermatrix methods to further improve phylogenetic data acquisition pipelines. We evaluated the overall costs (time and money) in order to identify the best compromise for phylogenetic data sampling in non-model animal taxa. Although sequencing full mitogenomes seems to constitute the best compromise both in terms of costs and node support, they are known to induce biases in phylogenetic reconstructions. Rather, we recommend to systematically include loci commonly used for phylogenetics and taxonomy (i.e. DNA barcodes, rRNA genes, full mitogenomes, etc.) among the other loci when designing baits for capture.


Assuntos
Filogenia , Animais , Custos e Análise de Custo , Perfilação da Expressão Gênica , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Moluscos/classificação , Moluscos/genética , Análise de Sequência de DNA
5.
Parasitol Res ; 118(5): 1417-1428, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30915549

RESUMO

The monogenean Microcotyle erythrini is atypical because it has been recorded from several fish host species in the Mediterranean Sea and Atlantic Ocean, in contrast to many species which are considered strictly specific. This could indicate a true lack of specificity or that several cryptic species are involved. This paper is a partial attempt to solve this problem. Specimens of a monogenean resembling M. erythrini were collected from bogues, Boops boops, caught off Algeria. A comparison with published descriptions and with museum specimens of M. erythrini did not yield any clear morphological difference. However, sequences of cytochrome c oxidase subunit I (COI) differed by 16.3% from that of M. erythrini (from GenBank, material collected from the type-host Pagellus erythrinus), indicating that the species was different. The species from B. boops is therefore described here as Microcotyle isyebi n. sp. and differential diagnoses with Microcotyle species from the Mediterranean and from sparids are provided. These results suggest that a molecular re-evaluation of other M. erythrini-like specimens from various fish hosts could reveal the existence of additional parasite biodiversity.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Trematódeos/classificação , Argélia , Animais , Oceano Atlântico , Peixes/parasitologia , Mar Mediterrâneo , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação
6.
Syst Parasitol ; 96(8): 681-694, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31576478

RESUMO

Allogastrocotyle bivaginalis Nasir & Fuentes Zambrano, 1983, the sole species of Allogastrocotyle Nasir & Fuentes Zambrano, 1983, was described from Trachurus lathami Nichols off Venezuela and never recorded since. We found monogeneans on Trachurus picturatus (Bowdich) (Carangidae) off the Algerian coast, Mediterranean Sea, which had the characteristics of the genus, including, especially, paired vaginae. We compared them to the single available specimen of A. bivaginalis, the holotype. Unfortunately, this holotype does not show clamp structure and soft internal anatomy. Our specimens were similar to A. bivaginalis in most characteristics such as body shape, vaginal openings, and number of testes, clamps and hooks in genital atrium. We detected minor differences in clamp structure but could not ascertain if these were the result of incomplete observations in the original description of real morphological differences. The host fish of our specimens were barcoded (cox1) confirming their specific identity. A phylogenetic analysis of cox1 sequences showed that our sequences of A. bivaginalis were distinct from those of Pseudaxine trachuri Parona & Perugia, 1889 (distance > 15%) and of several other gastrocotylids. Finally, we could not distinguish our Mediterranean specimens from A. bivaginalis, neither on the base of morphology (because the original description is incomplete) nor on molecules (because molecular information is lacking on A. bivaginalis from Venezuela) and ascribe them to A. bivaginalis. However, hosts are different, and localities are widely separated, so it is likely that future study will show that the species from the Mediterranean is a distinct, new, species.


Assuntos
Perciformes/parasitologia , Filogenia , Trematódeos/classificação , Trematódeos/genética , Argélia , Animais , Feminino , Masculino , Mar Mediterrâneo , Especificidade da Espécie , Trematódeos/anatomia & histologia
7.
Syst Parasitol ; 96(2): 131-147, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30701382

RESUMO

Parasite biodiversity of fish of the southern part of the Mediterranean sea is still incompletely explored. We describe here Microcotyle visa n. sp. from the gill filaments of the bluespotted seabream Pagrus caeruleostictus (Valenciennes) (Sparidae) collected off the Algerian coast. The identity of fish hosts was confirmed by barcoding. Microcotyle visa n. sp. is herein described and illustrated. Analysis of the cox1 gene of the monogeneans revealed minor intraspecific variation (1.4%), an order of magnitude lower than the distance between this species and other Microcotyle species (10-15 %). Microcotyle visa n. sp. is distinguished from Microcotyle erythrini van Beneden & Hesse, 1863, a congener infesting sparids, on the basis of morphological (size of clamps, number of testes) and molecular (cox1) differences. This is the fourth member of the genus known to parasitise a sparid host. A species of Paramicrocotyle sp. included in the molecular analysis was nested within a robust Microcotyle + Paramicrocotyle clade; in the absence of demonstrated molecular and morphological differences, we consider that Paramicrocotyle Caballero & Bravo-Hollis, 1972 is a junior synonym of Microcotyle van Beneden & Hesse, 1863 and transfer two species of Paramicrocotyle as Microcotyle danielcarrioni (Martinez & Barrantes, 1977) n. comb. and Microcotyle moyanoi (Villalba & Fernandes, 1986) n. comb.


Assuntos
Brânquias/parasitologia , Perciformes/parasitologia , Trematódeos/classificação , Trematódeos/fisiologia , Animais , Ciclo-Oxigenase 1/genética , Mar Mediterrâneo , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/genética
8.
Syst Parasitol ; 93(2): 115-28, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26790677

RESUMO

Based on light and electron microscopical studies of males and mature females, two new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) are described from the ovary of groupers, Epinephelus spp. (Perciformes; Serranidae), in the Mediterranean Sea off Tunisia (near Sfax): Philometra aenei n. sp. from the white grouper E. aeneus (Geoffroy Saint-Hilaire) and P. tunisiensis n. sp. from the goldblotch grouper E. costae (Steindachner). Identification of both fish hosts was confirmed by barcoding of the infected fish specimens. Philometra aenei is mainly characterised by the length of conspicuously distended spicules (108-123 µm), the presence of a distinct dorsal barb at the middle region of the gubernaculum and a distinct protuberance consisting of two dorsolateral lamellar parts separated from each other by a smooth median field at its distal tip, a V-shaped mound on the male caudal extremity and by the body length of the males (2.34-3.05 mm). The male of this species was found to possess minute deirids in the cervical region, which is quite exceptional within the Philometridae. Philometra tunisiensis is distinguished from other gonad-infecting congeneric species parasitising serranids by the length of the needle-like spicules and gubernaculum (201-219 and 78-87 µm, respectively), spicule length representing 9-11% of body length, the gubernaculum/spicules length ratio of 1:2.52-2.77, the length of oesophagus in the male comprising 15-16% of the body length, the absence of a dorsal protuberance on the distal lamellar part of the gubernaculum and a pair of large papillae posterior to the cloaca, a dorsally interrupted mound on the male caudal extremity and the body length of the male (2.01-2.42 mm). The presence of three morphologically very different species of Philometra in congeneric hosts in the Mediterranean Sea confirms a high degree of host specificity of these gonad-infecting nematodes parasitising groupers.


Assuntos
Dracunculoidea/classificação , Especificidade de Hospedeiro , Perciformes/parasitologia , Animais , Dracunculoidea/anatomia & histologia , Dracunculoidea/ultraestrutura , Feminino , Gônadas/parasitologia , Masculino , Mar Mediterrâneo , Microscopia Eletrônica de Varredura , Especificidade da Espécie , Tunísia
9.
Genetica ; 143(2): 207-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25351554

RESUMO

Using two distinct identification methods, one based on morphological characters only and the other combining morphological and molecular characters (integrative identification method), we investigated the differences in the biodiversity patterns of red seaweed communities associated with kelp forests at various spatial scales: the regional diversity of Brittany, France (γ-diversity), the local diversity at different Breton sites (α-diversity) and the differentiation in species diversity and abundances among those sites (ß-diversity). To characterise α and ß diversities, we conducted an initial survey in winter 2011 at 20 sites belonging to four different sub-regions, with specimens collected from six quadrats of 0.10 m(2) at each site, three in the tidal zone dominated by Laminaria digitata and three in the zone dominated by Laminaria hyperborea. To further characterise the regional diversity, we carried out another survey combining several sampling methods (quadrats and visual census) in different seasons (winter, spring and summer) and different years (2011 and 2012). In all, we collected 1990 specimens that were assigned to 76 taxa with the identification method based on morphological characters and 139 taxa using the integrative method. For γ and α diversity, the use of molecular characters revealed several cases of cryptic diversity and both increased the number of identified taxa and improved their taxonomic resolution. However, the addition of molecular characters for specimen identification only slightly affected estimates of ß-diversity.


Assuntos
Biodiversidade , Laminaria/classificação , Análise de Sequência de DNA/métodos , DNA de Plantas/genética , França , Geografia , Kelp/classificação
10.
PLoS Genet ; 7(3): e1002014, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21423668

RESUMO

Polycomb repressive complex 2 (PRC2) is a key regulator of epigenetic states catalyzing histone H3 lysine 27 trimethylation (H3K27me3), a repressive chromatin mark. PRC2 composition is conserved from humans to plants, but the function of PRC2 during the early stage of plant life is unclear beyond the fact that it is required for the development of endosperm, a nutritive tissue that supports embryo growth. Circumventing the requirement of PRC2 in endosperm allowed us to generate viable homozygous null mutants for FERTILIZATION INDEPENDENT ENDOSPERM (FIE), which is the single Arabidopsis homolog of Extra Sex Combs, an indispensable component of Drosophila and mammalian PRC2. Here we show that H3K27me3 deposition is abolished genome-wide in fie mutants demonstrating the essential function of PRC2 in placing this mark in plants as in animals. In contrast to animals, we find that PRC2 function is not required for initial body plan formation in Arabidopsis. Rather, our results show that fie mutant seeds exhibit enhanced dormancy and germination defects, indicating a deficiency in terminating the embryonic phase. After germination, fie mutant seedlings switch to generative development that is not sustained, giving rise to neoplastic, callus-like structures. Further genome-wide studies showed that only a fraction of PRC2 targets are transcriptionally activated in fie seedlings and that this activation is accompanied in only a few cases with deposition of H3K4me3, a mark associated with gene activity and considered to act antagonistically to H3K27me3. Up-regulated PRC2 target genes were found to act at different hierarchical levels from transcriptional master regulators to a wide range of downstream targets. Collectively, our findings demonstrate that PRC2-mediated regulation represents a robust system controlling developmental phase transitions, not only from vegetative phase to flowering but also especially from embryonic phase to the seedling stage.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas Repressoras/metabolismo , Plântula/fisiologia , Sementes/fisiologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Segregação de Cromossomos , Cromossomos de Plantas/fisiologia , Quinases Ciclina-Dependentes/genética , Flores/genética , Flores/fisiologia , Perfilação da Expressão Gênica , Histonas/metabolismo , Homozigoto , Fenótipo , Proteínas do Grupo Polycomb , Ligação Proteica , Proteínas Repressoras/genética , Plântula/genética , Sementes/genética
11.
PeerJ ; 12: e17904, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39346042

RESUMO

Specimens of a flat and dark brown land planarian were found in a plant nursery in North Carolina, USA in 2020. On the basis of examination of photographs of the live specimens only, the specimens were considered as belonging to Obama nungara, a species originally from South America, which has now invaded a large part of Europe. Unexpectedly, a molecular analysis revealed that the specimens did not belong to this species, neither to the genus Obama. We then undertook its histological study, which finally confirmed that the species is a member of the genus Amaga: the species is herein described as a new species, Amaga pseudobama n. sp. The species has been found in three locations in North Carolina and some infested plants were from Georgia. We reinvestigated specimens collected in Florida in 2015 and found that they also belong to this species. Citizen science observations suggest its presence in other states. Therefore, it is likely that A. pseudobama has already invaded a part of south-east USA and that the invasion took place more than ten years ago. The complete 14,909 bp long mitochondrial genome was obtained. The mitogenome is colinear with those of other Geoplanidae and it was possible to find and annotate a tRNA-Thr, which has been reported missing in several geoplanids. Amaga pseudobama shares with other Geoplaninae the presence of alternative start codons in three protein-coding genes of its mitogenome. The availability of this new genome helped us to improve our annotations of the ND3 gene, for which an ATT start codon is now suggested. Also, the sequence of the ATP6 gene raised questions concerning the use of genetic code 9 to translate the protein-coding genes of Geoplanidae, as the whole translated protein would not contain a single methionine residue when using this code. Two maximum likelihood phylogenies were obtained from genomic data. The first one was based on concatenated alignments of the partial 28S, Elongation Factor 1-alpha (EF1) and cox1 genes. The second was obtained from a concatenated alignment of the mitochondrial proteins. Both strictly discriminate A. pseudobama from O. nungara and instead associate it with Amaga expatria. We note that the nine species currently accepted within Amaga can be separated into two groups, one with extrabulbar prostatic apparatus, including the type species A. amagensis, and one with intrabulbar prostatic apparatus, including the new species A. pseudobama. This suggests that species of the latter group should be separated from Amaga and constitute a new genus. This finding again illustrates the possible emergence of new invasive species in regions naturally devoid of large land planarians, such as North America. Amaga pseudobama thus deserves to be monitored in the USA, although its superficial resemblance to O. nungara and Geoplana arkalabamensis will complicate the use of photographs obtained from citizen science. Our molecular information provides tools for this monitoring.


Assuntos
Espécies Introduzidas , Animais , Genoma Mitocondrial/genética , Filogenia , Platelmintos/genética , Platelmintos/classificação , North Carolina
12.
Parasite ; 31: 5, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38334685

RESUMO

Avian haemosporidian parasites (order Haemosporida, phylum Apicomplexa) are blood and tissue parasites transmitted by blood-sucking dipteran insects. Three genera (Plasmodium, Haemoproteus and Leucocytozoon) have been most often found in birds, with over 270 species described and named in avian hosts based mainly on the morphological characters of blood stages. A broad diversity of Haemoproteus parasites remains to be identified and characterized morphologically and molecularly, especially those infecting birds of prey, an underrepresented bird group in haemosporidian parasite studies. The aim of this study was to investigate and identify Haemoproteus parasites from a large sample comprising accipitriform raptors of 16 species combining morphological and new molecular protocols targeting the cytb genes of this parasite group. This study provides morphological descriptions and molecular characterizations of two Haemoproteus species, H. multivacuolatus n. sp. and H. nisi Peirce and Marquiss, 1983. Haemoproteus parasites of this group were so far found in accipitriform raptors only and might be classified into a separate subgenus or even genus. Cytb sequences of these parasites diverge by more than 15% from those of all others known avian haemosporidian genera and form a unique phylogenetic clade. This study underlines the importance of developing new diagnostic tools to detect molecularly highly divergent parasites that might be undetectable by commonly used conventional tools.


Title: Nouveau clade phylogénétique de parasites de rapaces Accipitridae du genre Haemoproteus (Haemosporida, Haemoproteidae), avec description d'une nouvelle espèce d'Haemoproteus. Abstract: Les parasites hémosporidies aviaires (ordre Haemosporida, phylum Apicomplexa) sont des parasites sanguins et tissulaires transmis par des insectes diptères hématophages. Trois genres (Plasmodium, Haemoproteus et Leucocytozoon) ont été le plus souvent trouvés chez les oiseaux, avec plus de 270 espèces décrites et nommées chez les hôtes aviaires en fonction principalement des caractères morphologiques des stades sanguins. Une grande diversité des Haemoproteus reste à identifier et à caractériser morphologiquement et génétiquement, en particulier ceux qui infectent les oiseaux de proie, un groupe d'oiseaux sous-représenté dans les études sur les hémosporidies. Le but de cette étude était d'étudier et d'identifier les Haemoproteus à partir d'un large échantillon comprenant des rapaces accipitriformes de 16 espèces, en combinant des protocoles morphologiques et de nouveaux protocoles moléculaires ciblant les gènes cytb de ce groupe de parasites. Cette étude fournit des descriptions morphologiques et des caractérisations moléculaires de deux espèces d'Haemoproteus, H. multivacuolatus n. sp. et H. nisi Peirce and Marquiss, 1983. Les Haemoproteus de ce groupe n'ont jusqu'à présent été trouvés que chez les rapaces accipitriformes et pourraient être classés dans un sous-genre ou même un genre distinct. Les séquences cytb de ces parasites divergent de plus de 15 % de celles de tous les autres genres d'hémosporidies aviaires connus et forment un clade phylogénétique unique. Cette étude souligne l'importance de développer de nouveaux outils de diagnostic pour détecter des parasites moléculairement très divergents qui pourraient être indétectables par les outils conventionnels couramment utilisés.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Infecções Protozoárias em Animais , Aves Predatórias , Animais , Haemosporida/genética , Filogenia , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Aves , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia
13.
PLoS Negl Trop Dis ; 17(2): e0011063, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36821543

RESUMO

Caterpillars of the Neotropical genus Lonomia (Lepidoptera: Saturniidae) are responsible for some fatal envenomation of humans in South America inducing hemostatic disturbances in patients upon skin contact with the caterpillars' spines. Currently, only two species have been reported to cause hemorrhagic syndromes in humans: Lonomia achelous and Lonomia obliqua. However, species identifications have remained largely unchallenged despite improved knowledge of venom diversity and growing evidence that the taxonomy used over past decades misrepresents and underestimates species diversity. Here, we revisit the taxonomic diversity and distribution of Lonomia species using the most extensive dataset assembled to date, combining DNA barcodes, morphological comparisons, and geographical information. Considering new evidence for seven undescribed species as well as three newly proposed nomenclatural changes, our integrative approach leads to the recognition of 60 species, of which seven are known or strongly suspected to cause severe envenomation in humans. From a newly compiled synthesis of epidemiological data, we also examine the consequences of our results for understanding Lonomia envenomation risks and call for further investigations of other species' venom activities. This is required and necessary to improve alertness in areas at risk, and to define adequate treatment strategies for envenomed patients, including performing species identification and assessing the efficacy of anti-Lonomia serums against a broader diversity of species.


Assuntos
Venenos de Artrópodes , Mariposas , Animais , Humanos , Larva , Venenos de Artrópodes/toxicidade , Hemorragia , América do Sul
14.
PeerJ ; 10: e12873, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35178303

RESUMO

BACKGROUND: The family Plectanocotylidae includes parasites of the gills of marine fish; although nine genera and about 20 species have been described, almost no molecular information is available. Putting aside Plectanocotyle elliptica Diesing, 1850, supposedly a parasite of the white perch Morone americana, never found again since its original description, two species were valid within Plectanocotyle Diesing, 1850 before this work: Plectanocotyle gurnardi (Van Beneden & Hesse, 1863) Llewellyn, 1941 and Plectanocotyle major Boudaya, Neifar & Euzet, 2006. METHODS: In this paper, we describe the third species of the genus Plectanocotyle and perform a comparative morphological and molecular analysis of the three species and of Triglicola obscura (Euzet & Suriano, 1974) Mamaev, 1976. Host fishes were also barcoded (COI) for confirmation of host identifications. RESULTS: Plectanocotyle lastovizae n. sp. is described from the gills of the streaked gurnard Chelidonichthys lastoviza collected off Algeria. The species is compared with specimens of Plectanocotyle cf. gurnardi (from C. lastoviza) from the same locality and P. major and T. obscura (both from the longfin gurnard C. obscurus). Molecules from Plectanocotyle cf. gurnardi could not be compared with P. gurnardi from the type-host and type-locality and we kept the status of the Mediterranean specimens as pending. Algeria is a new geographic record for P. major and T. obscura. Plectanocotyle lastovizae n. sp. is distinguished from the other species found in the Mediterranean by the measurements of clamps, number of testes, and COI sequences, with notable divergence (7.8-11.8%) from the other two species of the genus. DISCUSSION: We briefly present a list of currently known members of the family Plectanocotylidae, their biology and their hosts.


Assuntos
Bass , Perciformes , Trematódeos , Animais , Argélia , Trematódeos/genética , Perciformes/parasitologia , Brânquias/parasitologia
15.
PeerJ ; 10: e12725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35178290

RESUMO

BACKGROUND: New records of alien land planarians are regularly reported worldwide, and some correspond to undescribed species of unknown geographic origin. The description of new species of land planarians (Geoplanidae) should classically be based on both external morphology and histology of anatomical structures, especially the copulatory organs, ideally with the addition of molecular data. METHODS: Here, we describe the morphology and reproductive anatomy of a species previously reported as Diversibipalium "black", and the morphology of a species previously reported as Diversibipalium "blue". Based on next generation sequencing, we obtained the complete mitogenome of five species of Bipaliinae, including these two species. RESULTS: The new species Humbertium covidum n. sp. (syn: Diversibipalium "black" of Justine et al., 2018) is formally described on the basis of morphology, histology and mitogenome, and is assigned to Humbertium on the basis of its reproductive anatomy. The type-locality is Casier, Italy, and other localities are in the Department of Pyrénées-Atlantiques, France; some published or unpublished records suggest that this species might also be present in Russia, China, and Japan. The mitogenomic polymorphism of two geographically distinct specimens (Italy vs France) is described; the cox1 gene displayed 2.25% difference. The new species Diversibipalium mayottensis n. sp. (syn: Diversibipalium "blue" of Justine et al., 2018) is formally described on the basis of external morphology and complete mitogenome and is assigned to Diversibipalium on the basis of an absence of information on its reproductive anatomy. The type- and only known locality is the island of Mayotte in the Mozambique Channel off Africa. Phylogenies of bipaliine geoplanids were constructed on the basis of SSU, LSU, mitochondrial proteins and concatenated sequences of cox1, SSU and LSU. In all four phylogenies, D. mayottensis was the sister-group to all the other bipaliines. With the exception of D. multilineatum which could not be circularised, the complete mitogenomes of B. kewense, B. vagum, B. adventitium, H. covidum and D. mayottensis were colinear. The 16S gene in all bipaliine species was problematic because usual tools were unable to locate its exact position. CONCLUSION: Next generation sequencing, which can provide complete mitochondrial genomes as well as traditionally used genes such as SSU, LSU and cox1, is a powerful tool for delineating and describing species of Bipaliinae when the reproductive structure cannot be studied, which is sometimes the case of asexually reproducing invasive species. The unexpected position of the new species D. mayottensis as sister-group to all other Bipaliinae in all phylogenetic analyses suggests that the species could belong to a new genus, yet to be described.


Assuntos
Genoma Mitocondrial , Planárias , Animais , Genoma Mitocondrial/genética , Filogenia , Comores , Itália , França
16.
Parasite ; 28: 49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34096866

RESUMO

Cyclocotyla bellones Otto, 1823 (Diclidophoridae) is a monogenean characterised by an exceptional way of life. It is a hyperparasite that attaches itself to the dorsal face of isopods, themselves parasites in the buccal cavity of fishes. In this study, Cy. bellones was found on Ceratothoa parallela (Otto, 1828), a cymothoid isopod parasite of the sparid fish Boops boops off Algeria in the Mediterranean Sea. We provide, for the first time, molecular barcoding information of a hyperparasitic monogenean, the parasitic crustacean host, and the fish host, with COI sequences.


TITLE: Triple code-barre pour un hyperparasite, son hôte parasite et l'hôte lui-même : une étude de Cyclocotyla bellones (Monogenea) sur Ceratothoa parallela (Isopoda) sur Boops boops (Teleostei). ABSTRACT: Cyclocotyla bellones Otto, 1823 (Diclidophoridae) est un monogène caractérisé par un mode de vie exceptionnel. C'est un hyperparasite qui se fixe sur la face dorsale d'isopodes, eux-mêmes parasites dans la cavité buccale de poissons. Dans cette étude, Cy. bellones a été trouvé sur Ceratothoa parallela (Otto, 1828), un isopode cymothoïdé parasite du poisson sparidé Boops boops au large de l'Algérie, en mer Méditerranée. Nous fournissons, pour la première fois, des informations de codes-barres moléculaires d'un monogène hyperparasite, de l'hôte crustacé parasite et de l'hôte poisson, avec des séquences de COI.


Assuntos
Doenças dos Peixes , Isópodes , Parasitos , Perciformes , Trematódeos , Argélia , Animais , Peixes , Mar Mediterrâneo , Parasitos/genética , Trematódeos/genética
17.
Zootaxa ; 4951(2): zootaxa.4951.2.11, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33903410

RESUMO

The land flatworm Platydemus manokwari (Platyhelminthes, Geoplanidae) is recorded from the islands of Guadeloupe, Martinique, and Saint Martin in the Caribbean arc. Photographs and records were obtained mainly from citizen science and ranged from the end of 2018 to February 2021; several specimens were deposited in the collections of the Muséum National d'Histoire Naturelle in Paris, France. Thirty records were from Guadeloupe, but only one from Martinique and from Saint Martin, respectively. The COI sequences of 3 specimens from Guadeloupe show that they belong to the World haplotype also found in many countries. We also report P. manokwari from Fort Myers, Florida, USA, with molecular characterization, which was also the World haplotype. This is the first published record of P. manokwari for Guadeloupe, Martinique and Saint Martin and the second for islands in the Caribbean, after Puerto Rico.


Assuntos
Platelmintos , Animais , Guadalupe , Martinica , Platelmintos/classificação , Índias Ocidentais
18.
Parasite ; 27: 50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32808922

RESUMO

The presence/absence and number of vaginae is a major characteristic for the systematics of the Monogenea. Three gastrocotylid genera share similar morphology and anatomy but are distinguished by this character: Pseudaxine Parona & Perugia, 1890 has no vagina, Allogastrocotyle Nasir & Fuentes Zambrano, 1983 has two vaginae, and Pseudaxinoides Lebedev, 1968 has multiple vaginae. In the course of a study of Pseudaxine trachuri Parona & Perugia 1890, we found specimens with structures resembling "multiple vaginae"; we compared them with specimens without vaginae in terms of both morphology and molecular characterisitics (COI barcode), and found that they belonged to the same species. We also investigated the male copulatory organ (MCO) of this species, the accuracy of the original description of which is known to be a matter of debate. We found that the genital atrium is armed with 12 hooks arranged as a single circle and a central hollow stylet which is probably involved in traumatic insemination. We redescribed Pseudaxine trachuri based on newly collected specimens from off the coast of Algeria and Museum specimens from off France. Specimens from the type-host, Trachurus trachurus, were found to be similar, for both molecular sequences and morphology, to those found on Boops boops. We can therefore confirm, for the first time with molecular evidence, that B. boops is a host of this parasite. We consider that Pseudaxinoides was erected on the basis of an erroneous interpretation of structures which are not vaginae and, consequently, propose the transfer of most of its species to Pseudaxine, as P. australis (Lebedev, 1968) n. comb., P. bychowskyi (Lebedev, 1977) n. comb., P. caballeroi (Lebedev, 1977) n. comb., P. cariacoensis (Nasir & Fuentes-Zambrano, 1983) n. comb., and P. vietnamensis (Lebedev, Parukhin & Roitman, 1970) n. comb. We also propose Allogastrocotyle dillonhargisorum nom. nov. for Pseudaxine bivaginalis Dillon & Hargis, 1965 to avoid a secondary homonymy.


TITLE: Pas de vagin, un vagin ou plusieurs vagins ? Une étude intégrative de Pseudaxine trachuri (Monogenea, Gastrocotylidae) mène à une meilleure compréhension de la systématique de Pseudaxine et des genres apparentés. ABSTRACT: La présence/absence et le nombre de vagins est une caractéristique majeure de la systématique des Monogènes. Trois genres de Gastrocotylidae partagent une morphologie et une anatomie similaires mais se distinguent par ce caractère : Pseudaxine Parona & Perugia, 1890 n'a pas de vagin, Allogastrocotyle Nasir & Fuentes Zambrano, 1983 a deux vagins et Pseudaxinoides Lebedev, 1968 a plusieurs vagins. Au cours d'une étude de Pseudaxine trachuri Parona & Perugia 1890, nous avons trouvé des spécimens avec des structures ressemblant à des « vagins multiples ¼. Nous les avons comparés, pour la morphologie et les molécules (code à barres COI), à des spécimens sans vagin et avons constaté qu'ils appartenaient à la même espèce. Nous avons également examiné l'organe copulateur mâle (OCM) de cette espèce, dont l'exactitude de la description originale est connue pour être un sujet de débat. Nous avons constaté que l'atrium génital est armé de 12 crochets disposés en un seul cercle et d'un stylet central creux qui est probablement impliqué dans l'insémination traumatique. Nous avons redécrit Pseudaxine trachuri à partir de spécimens nouvellement collectés des côtes algériennes et de spécimens de Musée des côtes de France. Les spécimens de l'hôte type, Trachurus trachurus, se sont avérés similaires, pour les molécules et la morphologie, à ceux trouvés sur Boops boops. Nous pouvons donc confirmer, pour la première fois avec des preuves moléculaires, que B. boops est un hôte de ce parasite. Nous considérons que Pseudaxinoides a été érigé sur la base d'une interprétation erronée de structures qui ne sont pas des vagins et, par conséquent, proposons le transfert de la plupart de ses espèces à Pseudaxine, comme P. australis (Lebedev, 1968) n. comb., P. bychowskyi (Lebedev, 1977) n. comb., P. caballeroi (Lebedev, 1977) n. comb., P. cariacoensis (Nasir et Fuentes-Zambrano, 1983) n. comb. et P. vietnamensis (Lebedev, Parukhin & Roitman, 1970) n. comb. Nous proposons également Allogastrocotyle dillonhargisorum nom. nov. pour Pseudaxine bivaginalis Dillon & Hargis, 1965, pour éviter une homonymie secondaire.


Assuntos
Classificação , Trematódeos , Vagina , Argélia , Animais , Feminino , França , Masculino , Perciformes/parasitologia , Trematódeos/anatomia & histologia , Trematódeos/classificação , Vagina/anatomia & histologia
19.
PeerJ ; 8: e8385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32071801

RESUMO

BACKGROUND: Obama nungara is a species of land flatworm originating from South America; the species was recently described and distinguished from a similar species, Obama marmorata. Obama nungara has invaded several countries of Europe, but the extent of the invasion has not been thoroughly mapped. METHODS: In this article, based on a five and a half-year survey undertaken by citizen science, which yielded 530 records from 2013 to 2018, we analysed information about the invasion of Metropolitan France by O. nungara. We also investigated the variability of newly obtained cytochrome c oxidase 1 (COI) sequences of specimens from France, Italy and Switzerland. RESULTS: Obama nungara was recorded from 72 of the 96 Departments of Metropolitan France. The species is especially abundant along the Atlantic coast, from the Spanish border to Brittany, and along the Mediterranean coast, from the Spanish border to the Italian border. More than half of the records were from an altitude below 50 m, and no record was from above 500 m; mountainous regions such as the Alps, Pyrenees and Massif Central are not invaded. Local abundance can be impressive, with 100 of specimens found in a small garden. An analysis of our new COI sequences, combined with published sequences of specimens from several countries, confirmed that three clades comprise the species. The first clade, 'Brazil', is currently confined to this country in South America; the second clade, 'Argentina 2', was found in Argentina and in Europe, only in Spain; and the third, 'Argentina 1', was found in Argentina and in Europe, in Spain, Portugal, France, UK, Italy, Belgium, and Switzerland. This suggests that two clades of O. nungara from Argentina have invaded Europe, with one widely spread. DISCUSSION: The present findings strongly suggest that O. nungara is a highly invasive species and that the population which has invaded several countries in Europe comes from Argentina. The wide dispersion of the species and its reported local abundance, combined with the predatory character of the species, make O. nungara a potential threat to the biodiversity and ecology of the native soil fauna in Europe, and probably the most threatening species of all invasive land planarians present in Europe.

20.
PeerJ ; 8: e10098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240595

RESUMO

BACKGROUND: The land flatworm Amaga expatria Jones & Sterrer, 2005 (Geoplanidae) was described from two specimens collected in Bermuda in 1963 and 1988 and not recorded since. METHODS: On the basis of a citizen science project, we received observations in the field, photographs and specimens from non-professionals and local scientists in Martinique and Guadeloupe. We barcoded (COI) specimens from both islands and studied the histology of the reproductive organs of one specimen. Based on Next Generation Sequencing, we obtained the complete mitogenome of A. expatria and some information on its prey from contaminating DNA. RESULTS: We add records from 2006 to 2019 in two French islands of the Caribbean arc, Guadeloupe (six records) and Martinique (14 records), based on photographs obtained from citizen science and specimens examined. A specimen from Martinique was studied for histology of the copulatory organs and barcoded for the COI gene; its anatomy was similar to the holotype, therefore confirming species identification. The COI gene was identical for several specimens from Martinique and Guadeloupe and differed from the closest species by more than 10%; molecular characterisation of the species is thus possible by standard molecular barcoding techniques. The mitogenome is 14,962 bp in length and contains 12 protein coding genes, two rRNA genes and 22 tRNA genes; for two protein genes it was not possible to determine the start codon. The mitogenome was compared with the few available mitogenomes from geoplanids and the most similar was Obama nungara, a species from South America. An analysis of contaminating DNA in the digestive system suggests that A. expatria preys on terrestrial molluscs, and citizen science observations in the field suggest that prey include molluscs and earthworms; the species thus could be a threat to biodiversity of soil animals in the Caribbean.

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