Spatial Distribution of Trophic Groups of Amoebae Around the Root Zone of Zea Mays Mycorrhizal With Rhizophagus Intraradices Grown in Microcosms

Fitness and productivity of most terrestrial plants depend on early associations with arbuscular mycorrhizal fungi and mutualistic bacteria. Plants select most of the microbial communities cohabiting their roots and mycorrhizosphere, attracting also all types of microbial predators. Naked amoebae are among the most voracious predators inflicting significant changes in soils bacterial and fungal populations. We evaluated how roots of Zea mays with or without Rhizophagus intraradices mycorrhizosphere (AMF) influence trophic groups of amoebae, along vertical (3, 6, and 9-cm) and horizontal soil distribution (roots and free-root compartments) grown in microcosms after, 20 days. Amoebae community in Non-AMF showed a high species richness in the root zone at 3 to 6-cm depth, and at the two free-root compartment away from plants. Conversely, AMF and mycelium zones modified the amoeba community at 6 to 9-cm depth, recording higher diversity of trophic groups than unplanted soil compartments. The highest bacterivorous diversity was found at the closer compartment to AMF roots, but fungivorous amoebae was not recorded. Amoebae feeding preferences were similar in both AMF and Non-AMF microcosms in where bacterivorous amoebae were dominant, while protozoa-eating amoebae were more frequent at the mycelium compartments. Rare amoebae species were found in AMF microcosms in comparison to those recorded from Non-AMF and unplanted microcosms.

Ovalopodium rosalinum sp. nov., Planopodium haveli gen. nov, sp. nov., Planopodium desertum comb. nov. and new insights into phylogeny of the deeply branching members of the order Himatismenida (Amoebozoa)

The order Himatismenida (Amoebozoa, Discosea) comprises naked amoebae with an organic coat that is located on the dorsal surface of the cell. The phylogenetic relationships among deeply branching genera of the Himatismenida are unclear, as data on the species diversity of the himatismenid genera is largely restricted to the derived genus Cochliopodium. Here, we describe two new amoeba species that branch at the base of the order Himatismenida, evidenced by SSU rRNA gene and multigene analyses. Among them, a freshwater species Planopodium haveli gen. nov., sp. nov. has a dorsal cell coat consisting of flat, oval scales. This species forms a clade at the base of the Himatismenida, and the previously described Ovalopodium desertum, its closest relative, is transferred into the new genus as Planopodium desertum comb. nov. Although the two species are barely distinguishable by their sequence data, they are clearly distinct in morphology. Using this data, we can report the first evidence of a dorsal cell coat consisting of scales outside of the genus Cochliopodium. The other species has a marine origin and branches deeply, close to the root of the phylogenetic tree of Himatismenida. Based on the morphology of this amoeba, it should be described as Ovalopodium rosalinum sp. nov., a new species of the genus Ovalopodium. Analyses of the phylogenetic relationships and the ultrastructure of the deeply branching himatismenids, together with several of the newly obtained gene sequences of Parvamoeba and Cochliopodium, suggest that some elements of the dorsal cell coat of Ovalopodium may be ancestral for Himatismenida and have been partly retained in various more derived species of this clade, in particular, Cochliopodium gallicum. Although actin and Cox1 gene data do not resolve the higher-level relationships in Himatismenida, they correspond to the grouping of species within most genera.

Composition of morphotypes of naked amebae in soils of the forest-steppe zone of Ukraine

In the soils of the forest-steppe zone of Ukraine we found 12 morphotypes of naked amoebae: eruptive (Vahlkampfa sp. (1), Vahlkampfa sp. (2), Willaertia sp.), politactic (Polychaos dubium Schaeffer, 1917, Deuteramoeba mycophaga Page, 1988), monotactic (Saccamoeba stagnicola Page, 1974, Hartmannella vermiformis Page, 1967, Cashia limacoides Page, 1974), lens-like (Cochliopodium sp. (1)), striate (Thecamoeba striata Penard, 1890, Thecamoeba similis Lepsi, 1960), rugose (Thecamoeba terricola (Greef, 1866) Lepsi, 1960), fan-shaped (Vannella sp., Ripella platypodia Smirnov, Nassonova, Chao et Cavalier-Smith, 2007), mayorellian (Mayorella viridis Leidy, 1874, Mayorella cantabrigiensis Page, 1983, Mayorella sp.), dactylopodial (Korotnevella sp. (1), Vexillifera sp.), acanthopodial (Acanthamoeba sp. (1)), branched (Rhizamoeba sp. (1)), lingualate (Stenamoeba stenopodia Page, 1969). In terms of frequency of occurrence, the most common were amoebae of eruptive (91 %), fan-shaped (82), striate (69), lens-like (62), acanthopodial (62), mayorellian (55.5 ), monotactic (53 %) morphotypes, the least common are amoeba of the politactic (24 %) morphotype. In the soils of meadows, there are no amoeba of polytactic and rugose morphotypes, in soils under shrubs – rugose and branched morphotypes. The composition of morphotypes of naked amoebas in the soils of the forest-steppe zone of Ukraine is divided into two complexes: the first complex includes amoebae from the soils of forests and shrubs, the second – from the soils of meadows. The formation of the first complex of morphotypes of amoebae is influenced by the increased humidity and higher temperature of the soils in comparison with the other complex of morphotypes of amoebas.

Distribution of naked amoebae in the soils of the steppe zone of Ukraine

As a result of the study, in the steppe zone of Ukraine (Odessa, Mykolaiv, Kirovohrad region), 12 species of naked amoebas were identified, which according to the modern Eukaryot system belong to three molecular clusters Tubulinea Smirnov et al., 2005, Discosea Cavalier-Smith, 2004., Discoba Simpson and Hampl et al., 2009. This species Vahlkampfia sp. (1), Vahlkampfia sp. (2), Deuteramoeba mycophaga Page, 1988, Saccamoeba stagnicola Page, 1974, Vexillifera sp., Vannella sp. Ripellaplatypodia Smirnov, Nassonova, Chao et Cavalier-Smith, 2007, Cochliopodium sp. (1), Mayorella sp., Thecamoeba striata Penard, 1890, Stenamoeba stenopodia (Page, 1969) Smirnov et al., 2007, Acanthamoeba sp. (1). In the studied steppe soils, the most common were Vahlkampfia sp. (2), S. stenopodia, Vahlkampfia sp. (1), Vexillifera sp., Cochliopodium sp. (1); the least common – R. platypodia, D. mycophaga, T. striata, Mayorella sp. As a result of the cluster analysis, it was found that the largest share of common species is observed between Mykolaiv and Kirovograd regions (0.71) and Odessa and Kirovograd regions (0.53); the smallest is between the Odessa and Mykolaiv regions (0.43). According to the results of cluster analysis, the faunistic complexes of soil species of amoebae of the steppe region of Ukraine are united into two clusters: one of them being complexes characteristic of the Odessa region, and the other complexes of the Mykolaiv and Kirovograd regions. According to the results of nonparametric multidimensional scaling, it is established that the species complex of soil amoebae in the Kirovograd and Mykolaiv regions is determined by the increased soil temperature and acidity, compared to the Odessa region. As for moisture, this factor has little effect on the species complexes amoebae steppe region of Ukraine.

Diversity of Naked Amoebae in Soils of Forest Areas of Zhytomyr Region (Ukraine)

Here we consider the morphotypes and changing species composition of naked amoebae in soils of forest areas in Zhytomyr region (Ukraine). The species composition and morphotypes of amoebae are influenced by the microclimate of soil and litter. Complexes of naked amoebae in the study area constitute two clusters: one of broadleaf (oak) and mixed forests, another of coniferous forests. The most similar species compositions were found in soils of oak and mixed forests (64 % similarity). The least similar were amoebae complexes of coniferous forests and oak forests, and coniferous forests and mixed forests. Non-parametric multidimensional scaling (MDS) showed that species complex of amoebae of mixed forests and oak forests had moister and more acidic soils compared to coniferous forests.

The species composition of naked amoeba in epiphytic mosses of Zhytomyr region

From epiphytic habitats of Zhytomyr region we identified 16 species of naked amoebae. This species: Vahlkampfia sp. (1), Saccamoeba stagnicola (Page, 1974), Saccamoeba sp. (1), Cashia limacoides (Page, 1974), Korotnevella sp. (1), Vexillifera sp., Ripella platypodia (Smirnov, Nassonova, Chao et Cavalier-Smith, 2007), Ripella sp., Cochliopodium sp. (1), Mayorella cantabrigiensis (Page, 1983), Mayorella sp., Thecamoeba striata Penard, 1890, Thecamoeba sp., Stenamoeba stenopodia (Page, 1969; Smirnov et al., 2007), Acanthamoeba sp. (1), Stygamoeba polymorpha (Sawyer, 1975). The most common were the amoebae Cochliopodium sp., Acanthamoeba sp. (1), S. stenopodia, Vexillifera sp., the least common – T. striata, R. platypodia, Mayorella sp., S. stagnicola, Saccamoeba sp. (1), S. polymorpha. On the species composition of the naked amoebae in epiphytic habitats Zhytomyr region is affected by the humidity of the substrate: a decrease in humidity reduced the species richness of amoebae. The connection of the species composition of amoebae with height above the ground with increasing height above the ground decreases the species composition of amoebae. At the levels of 0–1,5 m, the most common amoeba occur (S. stenopodia, Cochliopodium sp. (1), M. cantabrigiensis, Acanthamoeba sp. (1)), at a height of 1–1,5 m, most amoeba disappear and the least appears common view of Thecamoeba sp. In wet mosses dominating species Vahlkampfia sp. (1), Vahlkampfia sp. (2), R. platypodia, S. stenopodia, Cochliopodium sp. (1), M. cantabrigiensis, Acanthamoeba sp. (1), dry epiphytes of the study area met C. limacoides, Korotnevella sp. (1), S. polymorpha. The most heterogeneous complexes of the wet habitats, while dry – fairly uniform. We identified all species can be considered everybody, meet as in mosses and aquatic and soil habitats.

Amoebozoa Luhe, 1913 in the water bodies of the Vinnytsia region

In the reservoirs of the Vinnytsia region, we have identified 12 species of naked amoebas. This species: Saccamoeba stagnicola Page, 1974, Saccamoeba sp., Thecamoeba striata (Penard, 1890) Schaeffer, 1926, Stenamoeba stenopodia (Page, 1969) Smirnov et al., 2007, Mayorella cantabrigiensis Page, 1983, Mayorella sp., Korotnevella diskophora Smirnov, 1999, Vexillifera sp., Acanthamoeba sp. (1), Cochliopodium sp., Vahlkampfia sp. (1), Vahlkampfia sp. (2). Two species of naked amoebae (Vahlkampfia sp. (1), Vahlkampfia sp. (2)) belong to heterolobosea amoeba from the group Discoba Simpson in Hampl et al., 2009. In terms of frequency of occurrence, the most common were the amoeba Vahlkampfia sp. (2), Vahlkampfia sp. (1), the least common are Acanthamoeba sp. (1), M. cantabrigiensis, S. stagnicola, Saccamoeba sp., Vexillifera sp., Mayorella sp., K. diskophora, the middle position on the frequency of occurrence is species of Cochliopodium sp., T. striata, S. stenopodia. The species lists of naked amoebas in the reservoirs of the Vinnytsia region are combined into two complexes. The first complex (swamps) contained the amoeba Vahlkampfia sp. (1), in the second (rivers and floodplain water bodies) – S. stagnicola, Saccamoeba sp., T. striata, S. stenopodia, M. cantabrigiensis, Mayorella sp., K. diskophora, Vexillifera sp., Acanthamoeba sp. (1), Cochliopodium sp., Vahlkampfia sp. (1), Vahlkampfia sp. (2). The formation of species complexes of naked amoebae in the water of Vinnytsia region affected by water temperature, water acidity, concentration of dissolved oxygen in the water and organic substances (permanganate oxidizability). The species found by us belong to 7 morphotypes: eruptive, monopodial, striate, lingulate, mayorellian, dactylopodial, acanthopodial, lens-like.

Diversity and Distribution of Naked Amoebae in Water Bodies of Sumy Region (Ukraine)

Taxonomy of naked amoebae and specifics of their distribution in water bodies of Sumy Region are presented. Our research identified 12 species of naked amoebae of 11 morphotypes. We established their ecological groups relative to abiotic aquatic factors: euryoxidic, stenooxidic, stenobiotic and those that survive in a wide range of organic matter content. According to the species composition, swamp and riparian species complexes of naked amoebae were identified. It was found that species complexes of amoeba are influenced by such factors as temperature, concentration of dissolved oxygen and organic compounds.