Molecular genetic studies on morphologically indistinguishable Myxobolus spp. infecting cyprinid fishes, with the description of three new species, M. alvarezae sp. nov., M. sitjae sp. nov. and M. eirasianus sp. nov.

AbstractWhile studying Myxobolus gill infections of cyprinid fishes, the authors found large, segmented plasmodia in three species: ide (Leuciscus idus), asp (Aspius aspius) and white bream (Blicca bjoerkna). As regards their size and morphology, the spores from these plasmodia corresponded to those of M. dujardini described from chub (Leuciscus cephalus). However, the 18S rDNA sequences of spores from the three cyprinids differed from those of M. dujardini. Based on molecular differences, this paper describes two new species: M. alvarezae sp. nov. from ide and asp, and M. sitjae sp. nov. from white bream. The two new species and M. dujardini had a similar tissue tropism, and infected the multilayered epithelium of the gill filaments. Histological examination of the infected filaments demonstrated that the large plasmodia with multiple buddings were formed from amalgamating small plasmodia. Besides carrying infection in the filamental epithelium, the three above fish species were infected by small intralamellar plasmodia as well. These plasmodia were filled by spores that resembled the roach parasite M. intimus both in morphology and seasonal development. The 18S rDNA sequences of ‘intimus-like’ spores from ide and asp differed only in some base pairs from spores found in the type host roach, and were identified as belonging to M. intimus. The spores found in white bream, however, showed 3.6-5.0% difference in DNA sequence from those of M. intimus; therefore, they have been described as M. eirasianus sp. nov. The aim of this paper was to demonstrate the importance of using molecular methods for separating and identifying morphologically corresponding or closely similar Myxobolus spp.

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Unexplored diversity of microscopic myxomycetes: evidence from environmental DNA

Plant Ecology and Evolution ◽

10.5091/plecevo.2019.1621 ◽

2019 ◽

Vol 152 (3) ◽

pp. 499-506 ◽

Cited By ~ 2

Author(s):

Oleg N. Shchepin ◽

Martin Schnittler ◽

Nikki H.A. Dagamac ◽

Dmitry V. Leontyev ◽

Yuri K. Novozhilov

Keyword(s):

New Species ◽

18S Rdna ◽

Sequence Similarity ◽

Phylogenetic Analyses ◽

Environmental Dna ◽

Full Length ◽

Detection Techniques ◽

Rdna Sequences ◽

18S Rdna Sequences ◽

Environmental Sequences

Background and aims – Recent studies showed the position of two slime mould species with microscopic sporocarps, Echinosteliopsis oligospora and Echinostelium bisporum, within the class Myxomycetes. These minute species are seldom seen in studies based on detection of sporocarps and can easily be confused with protosteloid amoebozoans.Methods – We searched all published ePCR data sets that targeted myxomycete 18S rDNA for the presence of environmental sequences similar to E. oligospora and Echinosteliales in traditional circumscription, and performed phylogenetic analyses that included short environmental sequences and full-length 18S rDNA sequences representing all the major groups of myxomycetes.Key results – We report 19 unique sequences which are closely related to E. bisporum or E. oligospora based on sequence similarity (73.1–95.2% similarity) and which form well-supported monophyletic clades with these species in phylogenetic analyses. They may represent new species that are not yet described. Our phylogeny based on full-length 18S rDNA sequences further confirms the position of E. bisporum and E. oligospora within myxomycetes and the paraphyly of the order Echinosteliales in its traditional circumscription.Conclusions – Our results show that ePCR-based studies can reveal myxomycete taxa that often escape detection by traditional approaches, including potentially new species, and thus provide valuable new data on diversity and ecology of myxomycetes. As such, strategies for studying myxomycetes biodiversity should be revised, focusing also on molecular detection techniques in addition to the sporocarp-based ones.

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Myxobolus species infecting the cartilaginous rays of the gill filaments in cyprinid fishes

Acta Parasitologica ◽

10.2478/s11686-008-0054-3 ◽

2008 ◽

Vol 53 (4) ◽

Cited By ~ 9

Author(s):

Kálmán Molnár ◽

Gábor Cech ◽

Csaba Székely

Keyword(s):

18S Rdna ◽

Rutilus Rutilus ◽

Molecular Methods ◽

Roach Rutilus Rutilus ◽

Myxobolus Species ◽

Rdna Sequences ◽

Gill Filaments ◽

18S Rdna Sequences ◽

Cyprinid Fishes ◽

Bleak Alburnus Alburnus

AbstractDuring a survey on myxosporean parasites of cyprinid fishes in Hungary, Myxobolus infections were found in the cartilaginous rays of the gill filaments in roach (Rutilus rutilus) and bleak (Alburnus alburnus). Myxobolus spp. causing the infections were studied by morphological, histological and molecular methods. Small plasmodia surrounded by chondrocytes contained relatively few spores which differed from each other and from the known Myxobolus spp. both in their morphology and 18S rDNA sequences. Both species, described as M. feisti sp. nov. and M. susanlimae sp. nov., are characterised by a specific cartilaginous histotropism.

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Two new species and two new records of myxomycetes from subtropical forests in China

Phytotaxa ◽

10.11646/phytotaxa.350.1.6 ◽

2018 ◽

Vol 350 (1) ◽

pp. 51 ◽

Cited By ~ 1

Author(s):

YANG GAO ◽

SHU-ZHEN YAN ◽

GAO-WEI WANG ◽

SHUANG-LIN CHEN

Keyword(s):

New Species ◽

New Records ◽

Phylogenetic Analyses ◽

Diagnostic Feature ◽

Subtropical Forests ◽

Rdna Sequences ◽

Two New Species ◽

18S Rdna Sequences ◽

First Time ◽

Partial 18S

Two new myxomycetes from subtropical forests of China, Arcyria aeruginosa sp. nov. and Diderma subochraceum sp. nov., are described and illustrated. Arcyria aeruginosa occurred on rotten stem of bamboo and differs from all known species of the genus in having dense spines on inner surface of cups. The diagnostic feature of D. subochraceum is single-layered peridium which dehisces by longitudinal or stellate slit. Preliminary phylogenetic analyses based on partial 18S rDNA sequences support the establishment of the two new species. Additionally, Didymium saturnus H.W. Keller and Fuligo luteonitens L.G. Krieglst. & Nowotny are reported from China for the first time.

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Morphology and Molecular Phylogeny of the Soil Ciliate Cyrtohymena seorakensis sp. n. (Ciliophora, Hypotricha, Oxytrichidae)

Zootaxa ◽

10.11646/zootaxa.4758.3.8 ◽

2020 ◽

Vol 4758 (3) ◽

pp. 561-572

Author(s):

ATEF OMAR ◽

JAE-HO JUNG

Keyword(s):

Phylogenetic Analysis ◽

New Species ◽

Molecular Phylogeny ◽

18S Rdna ◽

Indian Population ◽

Cortical Granules ◽

Moss Sample ◽

Rdna Sequences ◽

18S Rdna Sequences ◽

Soil Ciliate

The morphology and infraciliature of a new ciliate, Cyrtohymena seorakensis sp. n., discovered in a moss sample from South Korea, were investigated. The new species is distinguished from congeners by having rather fewer, randomly scattered, yellowish cortical granules, 23–30 adoral membranelles, invariably four transverse cirri in morphostatic specimens, and a total of 62 dorsal bristles on average. Phylogenetic analysis based on 18S rDNA sequences showed that the new species clusters with an Indian population of C. citrina.

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Aborjinia corallicola sp. n., a new nematode species (Nematoda: Marimermithidae) associated with the bamboo coral Acanella arbuscula (Johnson)

Systematic Parasitology ◽

10.1007/s11230-021-09996-y ◽

2021 ◽

Author(s):

Rickard Westerman ◽

Bárbara de Moura Neves ◽

Mohammed Ahmed ◽

Oleksandr Holovachov

Keyword(s):

New Species ◽

Excretory Pore ◽

Host Species ◽

18S Rdna ◽

Cold Water ◽

Nematode Species ◽

Rdna Sequences ◽

The Family ◽

18S Rdna Sequences ◽

A New Species

AbstractA new species of Aborjinia Özdikmen, 2010 is described from the tissues of the cold-water bamboo coral Acanella arbuscula (Johnson) from the northwest Atlantic. Aborjinia corallicolasp. n. is characterized by 18.4–33.2 mm long body in adults; outer labial and cephalic sensilla papilliform and located 14–21 µm from anterior end, amphideal aperture located 22–41 µm from anterior end, excretory pore indistinct, rectum and anal opening functional, convex-conoid tail with broadly rounded terminus, spinneret subventral. It is placed in the genus Aborjinia based on the combination of the following characters: outer labial and cephalic sensilla papilliform in shape and located in one circle, contrary to Marimermis Rutsov & Platonova, 1974 (outer labial and cephalic sensilla setiform) and Ananus Rubtsov, 1977 and Thalassonema Ward, 1933 (outer labial and cephalic sensilla in separate circles, if known). From Aborjinia eulagiscae Tchesunov & Spiridonov, 1985 the new species differs in much shorter body, much shorter tail, presence of caudal glands and spinneret in adults, different host species. Our finding represents the first report of a nematode in a parasitic relationship with a cold-water octocoral. Phylogenetic relationships between Aborjinia and other nematodes are analyzed based on 18S rDNA sequences. Summary of all presently known species and genera of the family Marimermithidae is also given.

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Phylogeny of the Thoracican Barnacles Based on 18S rDNA Sequences

Journal of Crustacean Biology ◽

10.1163/20021975-99990049 ◽

2000 ◽

Vol 20 (2) ◽

pp. 393-398 ◽

Cited By ~ 13

Author(s):

D. James Harris ◽

Laura S. Maxson ◽

Lee F. Braithwaite ◽

Keith A. Crandall

Keyword(s):

18S Rdna ◽

Rdna Sequences ◽

18S Rdna Sequences

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Assessing the Biodiversity of Monoraphidium Using 18S rDNA Sequences

Journal of Phycology ◽

10.1046/j.1529-8817.38.s1.25.x ◽

2002 ◽

Vol 38 (s1) ◽

pp. 9-9

Author(s):

M. W. Fawley ◽

K. P. Fawley ◽

M. L. Dean

Keyword(s):

18S Rdna ◽

Rdna Sequences ◽

18S Rdna Sequences

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Sarcocystis Attenuati N. Sp. (Apicomplexa: Sarcocystidae) Infecting the Asian Gray Shrew, Crocidura Attenuata (Insectivora: Soricidae), in China

10.21203/rs.3.rs-907878/v1 ◽

2021 ◽

Author(s):

junjie hu ◽

Jun Sun ◽

Yanmei Guo ◽

Hongxia Zeng ◽

Yunzhi Zhang ◽

...

Keyword(s):

Host Specificity ◽

Definitive Host ◽

18S Rdna ◽

Common Species ◽

Molecular Characteristics ◽

Intermediate Hosts ◽

Parasite Life Cycle ◽

Rdna Sequences ◽

Transmission Electron ◽

18S Rdna Sequences

Abstract Background: There are limited data on Sarcocystis in insectivores. The Asian gray shrew, Crocidura attenuata, is one of the most common species of insectivores in the family Soricidae distributed in South Asia and Southeast Asia. To date, Sarcocystis has never been recorded in this host.Methods: Tissues from 42 Asian gray shrews were collected in China in 2017 and 2018. Sarcocysts were observed using light (LM) and transmission electron microscopy (TEM). To complete the parasite life cycle, muscle tissues of the host infected with sarcocysts were force-fed to two beauty rat snakes, Elaphe taeniura. Individual sarcocysts from different Asian gray shrews and oocysts/sporocysts isolated from the small intestines and feces of the experimental snakes were selected for DNA extraction, and seven genetic markers, including two nuclear loci (18S rDNA and ITS1), three mitochondrial genes (cox1, cox3 and cytb), and two apicoplastic genes (rpoB and clpC), were amplified, sequenced and analyzed.Results: Sarcocysts were found in 17 of 42 (40.5%) Asian gray shrews. Under LM, the microscopic sarcocysts were exhibited saw-tooth-like protrusions measuring 3.3–4.5 μm. Ultrastructurally, the sarcocyst wall contained numerous lancet- or leaf-like villous protrusions, similar to type 9h. The experimental beauty rat snakes shed oocysts/sporcysts measuring 11.9–16.7 × 9.2–10.6 μm with a prepatent period of 10 to 11 days. Comparing these sequences with those previously deposited in GenBank revealed that the 18S rDNA sequences and cox1 sequences shared the highest similarity with those of S. scandentiborneensis recorded in tree shrews, Tuaia minor and T. tana (i.e., 97.6–98.3% and 100% identity, respectively). Phylogenetic analysis based on 18S rDNA, ITS1 or cox1 sequences revealed that this parasite formed an independent clade with Sarcocystis spp. that utilize small animals as intermediate hosts and snakes as the known or presumed definitive host. On the basis of morphological and molecular characteristics and host specificity, the parasite was proposed as a new species, named S. attenuati.Conclusions: Sarcocysts were recorded in Asian gray shrews for the first time. The sarcocysts were characterized morphologically and molecularly. The 18S rDNA and cox1 sequences of S. attenuati, named in the present study, shared the highest identities with those of S. scandentiborneensis. However, the sarcocysts of the two species of Sarcocystis were quite different under LM and TEM. Based on experimental infection, beauty rat snakes have been proven to be a definitive host of S. attenuati. As more species of Sarcocystis from insectivores and other small mammals are properly morphologically and molecularly characterized, we may gain a better understanding of the biodiversity, host specificity and evolution of Sarcocystis in the future.

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