Volume 55, Issue 4

2016

Publication date: 19.12.2016

Licence: None

Editorial team

Editor-in-Chief Krzysztof Wiąckowski

Issue content

Evidence Supporting the Concept of a Regionalized Distribution of Testate Amoebae in the Arctic

Louis Beyens, Anatoly Bobrov

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 197 - 209

https://doi.org/10.4467/16890027AP.16.019.6006

Forty different sites, represented by 1483 samples, ranging from Alaska eastwards to Siberia, have been studied to assess the circumpolar testate amoebae species diversity. A total of 378 species have been recorded. The most common taxa are cosmopolitan and are widely distributed across various arctic habitats. Statistical analysis of testate amoebae species at sites across the Arctic have yielded geographic clusters of sampling sites that have been matched with climatic regions in the Arctic. We put forward the hypothesis that the differences in testate amoebae diversity across the Arctic hint to the existence of protozoological arctic regions. The problems concerning the question of the origin of the testate amoebae in the Arctic are also discussed, with emphasis on two arctic flagship species.

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Description of a New Testate Amoebae Genus Meisterfeldia with Notes on the Systematics of the Suborder Phryganellina (Amebozoa; Tubulinea; Arcellinida)

Anatoly Bobrov

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 211 - 219

https://doi.org/10.4467/16890027AP.16.020.6007

The review on the systematics of the suborder Phryganellina is presented. The diagnosis of newly erected genus Meisterfeldia is provided. Three new species, namely Meisterfeldia chibisovi, Meisterfeldia wegeneri and Meisterfeldia polygonia, of testate amoeba family Cryptodifflugiidae are described. Two species, namely Meisterfeldia vanhoornei and Meisterfelsia turfacea are transferred from the genus Cryptodifflugia. The specimens of new genus are characterised by ovoid shell, which is bilaterally symmetrical and laterally compressed, composed of proteinaceous material without mineral particles; circular subterminal aperture placed on ventrally and obliquely cut apertural end, or it is situated on a well developed or poorly expressed neck inclined ventrally.

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Morphological and Morphometric Description of a Novel Shelled Amoeba Arcella gandalfi sp. nov. (Amoebozoa: Arcellinida) from Brazilian Continental Waters

Jordana C. Féres, Alfredo L. Porfírio-Sousa, Giulia M. Ribeiro, Gustavo M. Rocha, José Mauro Sterza, Maria Beatriz G. Souza, Carlos Eduardo A. Soares, Daniel J. G. Lahr

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 221 - 229

https://doi.org/10.4467/16890027AP.16.021.6008

Arcellinida are free-living lobose amoebae that produce an outer shell (test). Here, we describe a conspicuous new species, Arcella gandalfi sp. nov, from Brazilian continental waters, along with a morphological and biometrical characterization. Test diameter and test height are on average 81 and 71 respectively. This new species has an apical conical extension, which differentiates it from other Arcella species. A. gandalfi seems to be closely-related to A. brasiliensis, due to the distinct marginal ring (test brim) present only in these two species. Since A. gandalfi is easily identified by morphological features and due to its apparent geographic restriction to South America, we discuss its possible use as a new flagship species.

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New Freshwater Species of Centrohelids Acanthocystis lyra sp. nov. and Acanthocystis siemensmae sp. nov. (Haptista, Heliozoa, Centrohelea) from the South Urals, Russia

Elena A. Gerasimova, Andrey O. Plotnikov

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 231 - 237

https://doi.org/10.4467/16890027AP.16.024.6011

Two new species of centrohelids Acanthocystis lyra sp. nov. and A. siemensmae sp. nov. from the Pismenka River in the South Urals, Russia, have been studied with scanning electron microscopy. Cells of these species have both long and short spine scales with hollow shafts and circular basal plates. A. lyra has the long spine scales divided into two curved S-shaped branches possessing small teeth on their inner surface. The short spine scales have primary and secondary bifurcations. Every secondary branch ends with two teeth. A. siemensmae has both long and short scales with funnel-like apices, which possess small teeth. Based on the scale morphology A. lyra has been attributed to the A. turfacea species group, whereas A. siemensmae has been attributed to the A. pectinata species group, both according to classification proposed by Mikrjukov, 1997. Similarities and differences of the new species with other members of the genus Acanthocystis have been discussed.

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Molecular Phylogeny of the Marine Planktonic Dinoflagellate Oxytoxum and Corythodinium (Peridiniales, Dinophyceae)

Fernando Gómez, Kevin C. Wakeman, Aika Yamaguchi, Hisayoshi Nozaki

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 239 - 248

https://doi.org/10.4467/16890027AP.16.026.6095

The dinoflagellate generaOxytoxum and Corythodinium that account for more than fifty species are widespread in warm oceans. These genera have been considered synonyms and thecal plate designations varied among authors. Several planktonic and sand-dwelling genera have been placed within the Oxytoxaceae. We obtained the first molecular data based on small subunit (SSU) rRNA gene sequences ofOxytoxum and Corythodinium, including the type species (O. scolopax and C. tessellatum) and C. frenguellii and C. cristatum. The three species of Corythodinium branched together a strong support [bootstrap (BP) of 98%]. This formed a sister clade with moderate support (BP 75%) with O. scolopax that supported the generic split. Oxytoxaceae should exclusively remain for Oxytoxum and Corythodinium, as an independent group, unrelated to any other known dinoflagellate. Oxytoxum was characterized by spindle-shaped cells with an anterior narrow epitheca, an apical spine and little cingular displacement. Corythodinium exhibits relatively broad cell shapes, with wider epitheca and greater cingular displacement, and an obovate or pentangular anterior sulcal plate that noticeably indented the epitheca. This suggested the need of new combinations for species that were described as Oxytoxum and possessed the characteristics of Corythodinium.

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Trichodinids (Ciliophora) of Corydoras paleatus (Siluriformes) and Jenynsia multidentata (Cyprinodontiformes) from Argentina, with Description of Trichodina corydori n. sp. and Trichodina jenynsii n. sp.

Paula S. Marcotegui , Linda Basson, Sergio R. Martorelli

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 249 - 257

https://doi.org/10.4467/16890027AP.16.027.6096

During surveys of parasites of the pepper cory Corydoras paleatus Jenyns, 1842 and sided-livebearer Jenynsia multidentata Jenyns, 1842 from Samborombón River, Argentina, Trichodina corydori n. sp., Trichodina cribbi Dove and O’Donoghue, 2005 and T. jenynsii n. sp.were morphologically studied. Taxonomic and morphometric data for these trichodinids based on dry silver nitrate-impregnated specimens are presented. Trichodina corydori is characterized by a prominent blade apophysis, the section connecting the blade and central part is short, and the adoral ciliary spiral makes a turn of 370–380°. Trichodina jenynsii is characterized by curved blades and prominently-shaped denticle rays that are characteristically extremely long, tapering to thin sharp points in adult specimens. This study is the first formal report of these trichodinids from South America, and the description of two new species.

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Ultrastructure and Phylogeny of Pleistophora beebei sp. nov. (Microsporidia) Infecting the Amazonian Teleostean Brachyhypopomus beebei (fam. Hypopomidae)

Graça Casal, Edilson Rodrigues Matos, Sónia Rocha, José Sindeaux Neto, Saleh Al-Quraishy, Carlos Azevedo

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 259 - 268

https://doi.org/10.4467/16890027AP.16.022.6009

A new microsporidian, Pleistophora beebei sp. nov., parasitizing the freshwater benthopelagic teleostean fish Brachyhypopomus beebei Schultz, 1944 (fam. Hypopomidae) collected from the Amazon River is described based on molecular and morphological studies. The parasite develops in the skeletal muscle of the abdominal cavity, forming a whitish cyst-like containing several groups of two types of spores (macrospores and microspores), which were observed in close contact with the myofibrils. Small groups of macrospores (ovoid elongate, tapering more anteriorly than posteriorly and measuring about 7.8 ± 0.4 × 4.7 ± 0.2 µm) were observed among the numerous microspores (lightly pyriform to ellipsoidal with rounded ends, measured about 4.7 ± 0.3 × 2.8 ± 0.4 µm). Both types of spores possessed a single large posterior vacuole containing flocculent material. The ultrastructural aspects observed, together with the formation of a cyst-like, suggest that the parasite belongs to the genus Pleistophora. This taxonomic positioning was confirmed by the molecular analysis of the SSU rRNA gene and Maximum-likelihood (ML) inference. Comparison to similar species previously described, recognized this as a new species, herein named Pleistophora beebei sp. nov.

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Microsporidia in a Woodland Pool I. Lanatospora costata sp. n. (Opisthosporidia, Microsporidia), Parasite of Megacyclops viridis (Crustacea, Copepoda): Fine Structure and Molecular Phylogeny.

Jiří Vávra, Miroslav Hyliš, Ivan Fiala, Dominik Refardt, J. I. Ronny Larsson

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 269 - 280

https://doi.org/10.4467/16890027AP.16.023.6010

Lanatospora costatasp. n., a new microsporidian parasite of the adipose and connective tissue cells of Megacyclops viridis (Jurine, 1820) (Copepoda: Cyclopidae) is described. It was isolated from a woodland pool with a rich and diverse fauna of microsporidia-infected small crustaceans and insect larvae. The parasite is structurally similar to the genus Lanatospora Voronin, 1989, characterized by a complex decorated exospore. In the described species the exospore is armoured by a conspicuous layer of interwoven ribs forming labyrinth on the spore surface. SSU rRNA phylogeny places the organism in the “aquatic outgroup” of microsporidia (Vossbrinck et al. 2004), which includes a number of microsporidia from aquatic microcrustacea of the classes Copepoda and Cladocera. The increasing number of available SSU rRNA gene sequences of these microsporidia allows a more detailed interpretation of their developmental histories.

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New microsporidia, Glugea sardinellensis n sp (Microsporea, Glugeida) found in Sardinella aurita Valenciennes, 1847, collected off Tunisian coasts

Lamjed Mansour, Aouatef Thabet, Abdel Halim Harrath, Suliman Y. Al Omar, Ahmed Mukhtar, Shaban R. Sayed, Abdel-Azeem S. Abdel-Baki

Acta Protozoologica, Volume 55, Issue 4, 2016, pp. 281 - 290

https://doi.org/10.4467/16890027AP.16.028.6097

A new microsporidia Glugea sardinellensis n. sp. found in the teleost fish Sardinella aurita Valenciennes collected from the Tunisian coasts. The parasite develops in a large xenomas measuring 1–16 mm in diameter and is generally visible with naked eye in the connective tissue around the pyloric caeca of the host. Xenoma were often rounded, but would be occasionally ovoid or irregular shape, generally creamy but rarely opaque, and filled with mature spores. The spores were unikaryotic pyriform measuring 5–5.5 (5.25±0.24) µm in length and 2.5–3 (2.75±0.24) µm in width. The posterior vacuole was large and occupied more than half of the spore. Ultrastructural study indicated that the mature spore has 13–14 coils of polar filament arranged in one layer, and a rough exospore. Intermediate stages were rare and randomly distributed in the xenoma. Merogonial and sporogonial stages were uni or binucleate. The plasma membrane surrounding the meront was irregular and indented. The mean prevalence was 18.3% and it varied according to season and locality. The distribution of prevalence according to fish size indicated that small fish were primarily affected. Phylogenetic analysis using the partial sequence of the SSU rDNA showed consistent association with species of the genusGlugea. The most closely related species was Glugea atherinae Berrebi, 1979 with 98.5% similarity.

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Słowa kluczowe: Testate amoebae, biogeography, Arctic, climate, flagship species, biodiversity, Testate amoebae, Cryptodifflugiidae, taxonomy, new genus Meisterfeldia, three new species, tundra, subarctica, Russia, Testate amoeba, new species, morphology, morphometry, flagship species, Heliozoa, Centrohelids, Acanthocystis, protists, SEM, taxonomy, 18S ribosomal RNA, armored Dinophyta, Atlantic Ocean, Mediterranean Sea, phytoplankton, SSU rDNA phylogeny, taxonomy, thecate Dinoflagellata, Ciliophora, Trichodina, fish parasites, gill parasites, trichodinids, Argentina, Dimorphism, SSU rRNA gene, parasite, Brazil, Lower fungi, phylogeny, utrastructure, spore, exospore, Glugea, fish parasites, Mediterranean Sea, phylogeny, Gulf of Gabès, round sardinella, marine

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2016