Cucumispora dikerogammari n. gen. (Fungi: Microsporidia) infecting the invasive amphipod Dikerogammarus villosus: a potential emerging disease in European rivers

SUMMARYDikerogammarus villosus is an invasive amphipod that recently colonized the main rivers of Central and Western Europe. Two frequent microsporidian parasites were previously detected in this species, but their taxonomic status was unclear. Here we present ultrastructural and molecular data indicating that these two parasites are in fact a single microsporidian species. This parasite shares numerous characteristics of Nosema spp. It forms elongate spores (cucumiform), developing in direct contact with host cell cytoplasm; all developmental stages are diplokaryotic and the life cycle is monomorphic with disporoblastic sporogony. Initially this parasite was described as Nosema dikerogammariOvcharenko and Kurandina 1987. However, phylogenetic analysis based on the complete sequence of SSU rDNA places the parasite outside the genus Nosema and it is therefore ascribed to a new genus Cucumispora. The key features characteristic to this genus are: presence of a very well-developed, umbrella-shape anchoring disk covering the anterior part of polaroplast; arrangement of isofilar polar filament into 6–8 coils convoluted with different angles, voluminous diplokaryon, thin spore wall and relatively small posterior vacuole containing posterosome. The parasite infects most host tissues but mainly muscles. It showed high rates of horizontal trophic transmission and lower rates of vertical transmission.

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Pilferer, murderer of innocents or prey? The potential impact of killer shrimp (Dikerogammarus villosus) on crayfish

Aquatic Sciences ◽

10.1007/s00027-020-00762-8 ◽

2020 ◽

Vol 83 (1) ◽

Author(s):

Sara Roje ◽

Kateřina Švagrová ◽

Lukáš Veselý ◽

Arnaud Sentis ◽

Antonín Kouba ◽

...

Keyword(s):

Native Species ◽

Developmental Stages ◽

Aquatic Organisms ◽

Freshwater Ecosystems ◽

Signal Crayfish ◽

Dikerogammarus Villosus ◽

Native Communities ◽

Marbled Crayfish ◽

Invasive Amphipod ◽

The Impact

Abstract Freshwater ecosystems worldwide are facing the establishment of non-native species, which, in certain cases, exhibit invasive characteristics. The impacts of invaders on native communities are often detrimental, yet, the number and spread of non-native invasive species is increasing. This is resulting in novel and often unexpected combinations of non-native and native species in natural communities. While the impact of invaders on native species is increasingly well-documented, the interactions of non-native invaders with other non-native invaders are less studied. We assessed the potential of an invasive amphipod, the killer shrimp Dikerogammarus villosus (Sowinsky, 1894), to cope with other established invaders in European waters: North American crayfish of the Astacidae family—represented by signal crayfish Pacifastacus leniusculus (Dana, 1852), and the Cambaridae family—represented by marbled crayfish Procambarus virginalis Lyko, 2017. The main goal of this study was to investigate if killer shrimp, besides their role as prey of crayfish, can significantly influence their stocks by predating upon their eggs, hatchlings and free-moving early juveniles. Our results confirmed that killer shrimp can predate on crayfish eggs and hatchlings even directly from females abdomens where they are incubated and protected. As marbled crayfish have smaller and thinner egg shells as well as smaller juveniles than signal crayfish, they were more predated upon by killer shrimp than were signal crayfish. These results confirmed that the invasive killer shrimp can feed on different developmental stages of larger freshwater crustaceans and possibly other aquatic organisms.

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Ultrastructure and molecular phylogeny of Pleistophora hyphessobryconis (Microsporidia) infecting hybrid jundiara (Leiarius marmoratus × Pseudoplatystoma reticulatum) in a Brazilian aquaculture facility

Parasitology ◽

10.1017/s0031182015001420 ◽

2015 ◽

Vol 143 (1) ◽

pp. 41-49 ◽

Cited By ~ 5

Author(s):

ANDREW D. WINTERS ◽

INGEBORG M. LANGOHR ◽

MARCOS DE A. SOUZA ◽

EDSON M. COLODEL ◽

MAURO P. SOARES ◽

...

Keyword(s):

Skeletal Muscle ◽

Plasma Membrane ◽

Developmental Stages ◽

Polar Filament ◽

Inflammatory Cells ◽

Spore Wall ◽

Ornamental Fish ◽

Rdna Sequences ◽

16S Rdna Sequences ◽

Dense Mass

SUMMARYA microsporidian infecting the skeletal muscle of hybrid jundiara (Leiarius marmoratus × Pseudoplatystoma reticulatum) in a commercial aquaculture facility in Brazil is described. Affected fish exhibited massive infections in the skeletal muscle that were characterized by large opaque foci throughout the affected fillets. Histologically, skeletal muscle was replaced by inflammatory cells and masses of microsporidial developmental stages. Generally pyriform spores had a wrinkled bi-layer spore wall and measured 4·0 × 6·0 µm. Multinucleate meronts surrounded by a simple plasma membrane were observed. The polar filament had an external membrane and a central electron dense mass. The development of sporoblasts within a sporophorous vesicle appeared synchronized. Ultrastructural observations and molecular analysis of 16S rDNA sequences revealed that the microsporidian was Pleistophora hyphessobryconis. This study is the first report of a P. hyphessobryconis infection in a non-ornamental fish.

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Notes on the molecular taxonomy of the Proclossiana eunomia complex (Lepidoptera, Nymphalidae: Argynnini): analysis of DNA barcodes

Ukrainian Journal of Ecology ◽

10.15421/2018_206 ◽

2018 ◽

Vol 8 (1) ◽

pp. 222-232 ◽

Cited By ~ 1

Author(s):

R. V. Yakovlev ◽

N. A. Shapoval ◽

G. N. Kuftina ◽

A. V. Kulak ◽

S. V. Kovalev

Keyword(s):

Body Size ◽

Molecular Taxonomy ◽

Taxonomic Status ◽

Molecular Data ◽

Coi Gene ◽

Wing Pattern ◽

Molecular Approach ◽

Dna Barcodes ◽

Morphological Differences ◽

Proclossiana Eunomia

The Proclossiana eunomia (Esper, 1799) complex is currently composed of the several subspecies distributed throughout Palaearсtic region and North America. Despite the fact that some of the taxa have differences in wing pattern and body size, previous assumptions on taxonomy not supported by molecular data. Therefore, the identity of certain populations of this complex has remained unclear and the taxonomic status of several recently described taxa is debated. Here, we provide insights into systematics of some Palaearctic members of this group using molecular approach, based on the analysis of the barcoding fragment of the COI gene taking into account known morphological differences.

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Combination of nuclear and mitochondrial markers as a useful tool to identify Ctenophthalmus species and subspecies (Siphonaptera: Ctenophthalmidae)

Organisms Diversity & Evolution ◽

10.1007/s13127-021-00500-4 ◽

2021 ◽

Author(s):

Antonio Zurita ◽

Cristina Cutillas

Keyword(s):

Taxonomic Status ◽

Molecular Study ◽

Molecular Data ◽

Point Of View ◽

Morphological Data ◽

Molecular Approach ◽

Nuclear Marker ◽

Mitochondrial Markers ◽

Morphological Criteria ◽

Mtdna Markers

AbstractCtenophthalmus is considered the largest genus within the Order Siphonaptera. From a morphological point of view, only males of this genus can be identified at species and subspecies levels using morphological keys, whereas there are no morphological criteria in order to classify females at these taxonomical levels. Furthermore, the amount of available molecular and phylogenetic data for this genus is quite scarce so far. The main objective of this work was to assess the utility of the combination of nuclear and mitochondrial markers with respect to their ability to differentiate among different subspecies within the Ctenophthalmus genus. With this purpose, we carried out a comparative morphological and molecular study of three different subspecies (Ctenophthalmus baeticus arvernus, Ctenophthalmus nobilis dobyi, and Ctenophthalmus andorrensis catalaniensis) in order to clarify and discuss its taxonomic status. In addition, our study complemented the molecular data previously provided for Ctenophthalmus baeticus boisseauorum and Ctenophthalmus apertus allani subspecies. We sequenced five different molecular markers: EF1-α, ITS1, ITS2, cox1, and cytb. Our results confirmed that morphological data by themselves are not able to discriminate among Ctenophthalmus female taxa; however, the combination of the nuclear marker EF1-α together with mtDNA markers cytb and cox1 constituted a useful taxonomical and phylogenetic tool to solve this issue. Based on these results, we consider that the use of this molecular approach should be gradually used within Ctenophthalmus genus in order to complement its classical taxonomy and clarifying the complex taxonomy of other congeneric species of fleas.

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The role of NbTMP1, a surface protein of sporoplasm, in Nosema bombycis infection

Parasites & Vectors ◽

10.1186/s13071-021-04595-8 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Shiyi Zheng ◽

Yukang Huang ◽

Hongyun Huang ◽

Bin Yu ◽

Ni Zhou ◽

...

Keyword(s):

Indirect Immunofluorescence ◽

Selective Breeding ◽

Developmental Stages ◽

Transmembrane Protein ◽

Surface Protein ◽

Spore Wall ◽

Significant Inhibition ◽

Pcr Analysis ◽

Immunofluorescence Analysis ◽

Nosema Bombycis

Abstract Background Nosema bombycis is a unicellular eukaryotic pathogen of the silkworm, Bombyx mori, and is an economic and occupational hazard in the silkworm industry. Because of its long incubation period and horizontal and vertical transmission, it is subject to quarantine measures in sericulture production. The microsporidian life-cycle includes a dormant extracellular phase and intracellular proliferation phase, with the proliferation period being the most active period. This latter period lacks spore wall protection and may be the most susceptible stage for control. Methods In order to find suitable target for the selective breeding of N. bombycis-resistant silkworm strains, we screen highly expressed membrane proteins from the transcriptome data of N. bombycis. The subcellular localization of the candidate protein was verified by Indirect immunofluorescence analysis (IFA) and immunoelectron microscopy (IEM), and its role in N. bombycis proliferation was verified by RNAi. Results The N. bombycis protein (NBO_76g0014) was identified as a transmembrane protein and named NbTMP1. It is homologous with hypothetical proteins NGRA_1734 from Nosema granulosis. NbTMP1 has a transmembrane region of 23 amino acids at the N-terminus. Indirect immunofluorescence analysis (IFA) results suggest that NbTMP1 is secreted on the plasma membrane as the spores develop. Western blot and qRT-PCR analysis showed that NbTMP1 was expressed in all developmental stages of N. bombycis in infected cells and in the silkworm midgut. Downregulation of NbTMP1 expression resulted in significant inhibition of N. bombycis proliferation. Conclusions We confirmed that NbTMP1 is a membrane protein of N. bombycis. Reduction of the transcription level of NbTMP1 significantly inhibited N. bombycis proliferation, and this protein may be a target for the selective breeding of N. bombycis-resistant silkworm strains.

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Effects of Sublethal Cadmium Exposure on Antipredator Behavioural and Antitoxic Responses in the Invasive Amphipod Dikerogammarus villosus

PLoS ONE ◽

10.1371/journal.pone.0042435 ◽

2012 ◽

Vol 7 (8) ◽

pp. e42435 ◽

Cited By ~ 22

Author(s):

Pascal Sornom ◽

Eric Gismondi ◽

Céline Vellinger ◽

Simon Devin ◽

Jean-François Férard ◽

...

Keyword(s):

Cadmium Exposure ◽

Dikerogammarus Villosus ◽

Invasive Amphipod

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A new slipper lobster of the genus Petrarctus Holthuis, 2002 (Crustacea, Decapoda, Scyllaridae) from Southwest coast of India

Zootaxa ◽

10.11646/zootaxa.4329.5.5 ◽

2017 ◽

Vol 4329 (5) ◽

pp. 477 ◽

Cited By ~ 3

Author(s):

CHIEN-HUI YANG ◽

APPUKUTTANNAIR BIJU KUMAR ◽

TIN-YAM CHAN

Keyword(s):

New Species ◽

Deep Sea ◽

Genetic Information ◽

Anterior Part ◽

Molecular Genetic ◽

Taxonomic Status ◽

Molecular Genetic Analysis ◽

Andaman Sea ◽

Abdominal Somite ◽

A New Species

A new species of slipper lobster of the genus Petrarctus Holthuis, 2002 was discovered from southwestern India during a survey of deep sea crustaceans. The new species closely resembles P. veliger Holthuis, 2002 from the Andaman Sea and western Pacific but differs mainly in the color marking on abdominal somite I, having a relatively lower cardiac tooth but with better developed tubercles on the abdomen, as well as a differently shaped anterior part of the thoracic sternum. Molecular genetic analysis also confirms the distinct taxonomic status of the new species. To fix the identity of the type species of the genus, a neotype of P. rugosus (H. Milne Edwards, 1837) was selected from a recently collected Indian specimen with color and genetic information.

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Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales, Rhodophyta), previously recognized as G. mammillaris, from the southern coast of Vietnam

10.26686/wgtn.12509957.v1 ◽

2020 ◽

Author(s):

HN Le ◽

N Muangmai ◽

S Kheauthong ◽

Z Sun ◽

Giuseppe Zuccarello

Keyword(s):

New Species ◽

South China Sea ◽

South China ◽

Taxonomic Status ◽

Molecular Data ◽

The South China Sea ◽

The South ◽

Western Atlantic ◽

China Sea ◽

Coast Of Vietnam

© 2019 Japanese Society of Phycology Flattened Gracilaria species are widely distributed along the coasts of the South China Sea with more than 20 species recorded. Within the South China Sea, Gracilaria mammillaris has only been reported from Vietnam, but this species is likely restricted to the western Atlantic. This study aimed to reevaluate the taxonomic status of Vietnamese specimens of ‘G. mammillaris’ using combined morphological and molecular data. Our data clearly indicated that Vietnamese specimens were morphologically and genetically distinct from authentic G. mammillaris from the western Atlantic, and also other described flat Gracilaria species. We, therefore, propose that specimens from Vietnam originally identified as G. mammillaris be designated as a new species, Gracilaria phuquocensis sp. nov. Morphologically, G. phuquocensis can be distinguished from other flat Gracilaria species by its small thallus size, narrower blades, many medullary layers, abundant basal nutritive filaments within mature cystocarps, and tetrasporangial nemathecium. Our rbcL sequence analyses showed that the new species was sister to Gracilaria rhodymenioides from Thailand, and these two species formed a clade with cylindrical Gracilaria species. Our study contributes to clarification of the taxonomic status of misidentified specimens attributed to the flattened Gracilaria species in the South China Sea.

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Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales, Rhodophyta), previously recognized as G. mammillaris, from the southern coast of Vietnam

10.26686/wgtn.12509957 ◽

2020 ◽

Author(s):

HN Le ◽

N Muangmai ◽

S Kheauthong ◽

Z Sun ◽

Giuseppe Zuccarello

Keyword(s):

New Species ◽

South China Sea ◽

South China ◽

Taxonomic Status ◽

Molecular Data ◽

The South China Sea ◽

The South ◽

Western Atlantic ◽

China Sea ◽

Coast Of Vietnam

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A NEW SPECIES OF THE Pareas hamptoni COMPLEX (SQUAMATA, SERPENTES, PAREIDAE) FROM THE GOLDEN TRIANGLE

TAPROBANICA The Journal of Asian Biodiversity ◽

10.47605/tapro.v9i2.230 ◽

2020 ◽

pp. 174-193

Author(s):

Li Ding ◽

Zening Chen ◽

Chatmongkon Suwannapoom ◽

Tan Van Nguyen ◽

Nikolay A. Poyarkov ◽

...

Keyword(s):

New Species ◽

Yunnan Province ◽

Southern China ◽

Taxonomic Status ◽

Distinct Species ◽

Molecular Data ◽

Lower Number ◽

Actual Distribution ◽

Golden Triangle ◽

Morphological And Molecular Data

An investigation of the taxonomic status of Pareas hamptoni (Hampton's Slug snake) based on morphological and molecular data revealed a new distinct species from the Golden Triangle region (comprising parts of southern China, and adjacent Laos and Thailand). The new species is shown to be a sister species to P. hamptoni but can be separated from the latter by having 3–5 dorsal scale rows at midbody slightly keeled (vs 5–9 scales strongly keeled); a lower number of ventrals, 170–188 (vs 185–195); and a lower number of subcaudals, 67–91 (vs 91–99). The new species is currently known from northwestern Thailand, northern Laos, and the southern part of Yunnan Province in China at elevations of 1,160–2,280 m a.s.l. We suggest that the new species to be considered of Least Concern (LC) in the IUCN‘s Red List categories. Problems of taxonomy and actual distribution of the P. hamptoni complex are briefly discussed; our results show P. hamptoni is now reliably known only from Myanmar and Vietnam, but its occurrence in Yunnan Province of China is likely.

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