Microsporidia Alfvenia sibirica sp. n. and Agglomerata cladocera (Pfeiffer) 1895, from Siberian microcrustaceans and phylogenetic relationships within the "Aquatic outgroup" lineage of fresh water microsporidia.

Here we report on two microsporidia from freshwater crustaceans collected during the ongoing survey for microsporidia in the river Karasuk and adjacent waterbodies (Novosibirsk region, Western Siberia). The first species parasitized hypoderm and fat body of a cyclopid Cyclops sp. (Maxillopoda, Copedoda) and produced oval spores, measured 2.0×3.6µm (fixed) enclosed individually or in small groups in fragile sporophorous vesicles (SVs). We describe it here as Alfvenia sibirica sp. n. The second species infected the same tissues of a cladoceran Daphnia magna (Branchiopoda, Phyllopoda). Its spores were pyriform, 2.3×4.0µm (fixed), and resided in relatively persistent SVs in groups of 8-16. This species was identified as a Siberian isolate (Si) of Agglomerata cladocera (Pfeifer) because ultrastructurally it was hardly distinguishable from A. cladocera recorded from England from the same host (Larsson et al., 1996). A. cladocera (Si) shared 99% SSU rDNA sequence similarity to Binucleata daphniae from D. magna collected in Belgium (Refardt et al., 2008). The major outcome of our work is that we present molecular (SSUrDNA) characterization coupled with EM description, for representatives of two genera, Alfvenia (encompasses 3 described so far species) and Agglomerata (7 species), which allowed us to place these two genera on the phylogenetic tree. We also summarized the literature data on Alfvenia and Agglomerata spp., and provided their comparative morphological analysis. These two genera belong to so called "Aquatic outgroup" (Vossbrinck et al., 2004), a poorly resolved lineage, a sister to Amblyosporidae. This lineage probably includes majority of fresh water forms of microsporidia, most of which remain undescribed. SSUrDNA-based phylogenetic analysis and analysis of hosts suggest that diversification within the "Aquatic outgroup" could have been connected with the host switch from dipterans or copepods to cladocerans that had occurred in some ancestral Amblyospora-related lineage(s).

[THE MICROSPORIDIUM GLUGEA GASTEROSTEI VORONIN 1974 (MICROSPORIDIA: MARINOSPORIDIA) FROM THE THREE-SPINED STICKLEBACK GASTEROSTEUS ACULEATUS (ACTINOPTERYGII: GASTEROSTEIFORMES) AS AN INDEPENDENT SPECIES].

The microsporidium Glugea gasterostei from the three-spined stickleback Gasterosteus aculeatus was described as an independent species basing upon morphological and ecological traits of the parasite (Voronin, 1974), further supported by ultrastructural characters of its spores (Voronin, 1983). During the revision of microsporidia of the genus Glugea (Canning, Lom, 1986; Lom, 2002), the validity of this species was doubted and it was synonymized with G. anomala. Nevertheless, the molecular phylogenetic analysis performed in the present study showed the unique molecular haplotype of small subunit rRNA gene of G. gasterostei (Genbank accession number KM977990) and its close relatedness to G. anomala, G. atherinae and G. hertwigi (sequence similarity of 99.7 %). One of typical characters of G. gasterostei, as opposed to G. anomala, is the formation of xenomas on inner tissues and not on the surface of infected fishes. This feature is retained even after the infection of different host species. Taken together, these data confirm the validity of G. gasterostei as a separate species among closely related taxa that had diverged comparatively recently.

From Russia with lobe: genetic differentiation in trilobed uncus Ostrinia spp. follows food plant, not hairy legs.

Trilobed uncus taxa of the genus Ostrinia (Lepidoptera, Crambidae) illustrate the complex relationship, at early stages of speciation, between reproductive isolation and differentiation in morphology, resource use and genetic variation. On the basis of behaviour and ecology, we recently hypothesized that individuals with small mid-tibiae belong to two distinct species depending on host plant--O. nubilalis and O. scapulalis sensu Frolov et al. (2007) feeding on maize and on a number of dicotyledons, respectively. Individuals with small, medium or massive mid-tibiae would all belong to O. scapulalis as long as they feed on these dicotyledons. This contrasts with previous taxonomy, which distinguished three species by male mid-tibia morphology, regardless of host plant. Here, we test our hypothesis by examining the genetic structure of Ostrinia populations from regions with mid-tibia polymorphism--Western Russia and Kazakhstan--and comparing it with that of French populations where only small mid-tibiae occur. Results support two predictions: (1) maize- and dicotyledon-collected populations are genetically differentiated from each other like in France, and (2) dicotyledon-collected populations show no genetic evidence of consisting of more than one species. Between-species differentiation was unrelated to geographic distance, despite significant isolation by distance within species. The distinction between two and only two species differing by host plant thus holds at continental scale. Interestingly, one microsatellite locus contributed ∼10 times more than the others to differentiation between both taxa. This deserves further investigation, as it might reveal a linkage between this outlier and loci involved in host-plant adaptation and/or reproductive isolation.

Polymorphism of Beauveria bassiana (Deuteromycota: Hyphomycetes) strains isolated from Ixodes ricinus (Acari: Ixodidae) in Moldova.

Polymorphism of 10 Beauveria bassiana strains, isolated from Ixodes ricinus in Moldova, was evaluated using traditional (morphological and cultural properties) and molecular (RAPD patterns and ITS sequences) methods. The isolates differed greatly in morphological and cultural features, such as color, consistence, and growth rate. Four RAPD-PCR markers were used to evaluate genetic diversity of the strains. Phylogenetic neighbor-joining analysis of RAPD patterns divided strains into 3 major clades. The ITS sequences of 8 strains were identical to those of known B. bassiana strains. Two subsets (1 and 2) different by one nucleotide change were found in the ITS1 region. One strain of subset 1 was different from known B. bassiana strains by possessing 2 point mutations in the ITS region. RAPD-based clustering correlated to ITS sequence and colony morphology-based grouping of the strains.

Did the introduction of maize into Europe provide enemy-free space to Ostrinia nubilalis? Parasitism differences between two sibling species of the genus Ostrinia.

We examined whether maize offers enemy-free space (EFS) to its pest Ostrinia nubilalis, and may thereby have contributed to its divergence from the sibling species, Ostrinia scapulalis, feeding mainly on mugwort, when introduced into Europe five centuries ago. We collected Ostrinia larvae on maize (70 populations, 8425 individuals) and mugwort (10 populations, 1184 individuals) and recorded parasitism using both traditional (counting emerging parasitoids) and molecular methods (detection by specific polymerase chain reaction). The main parasitoid was Macrocentrus cingulum (Braconidae). On mugwort, parasitism was twice that on maize, and parasitoid-related mortality was 8 times higher. This suggests that maize affords substantial EFS to Ostrinia feeding on it. The lower Mortality:Infestation ratio in maize suggests that O. nubilalis' immune response might be stronger than that of O. scapulalis. If so, adapting to maize and diverging from O. scapulalis would decrease the impact of parasitism on O. nubilalis at both ecological and evolutionary levels.