Ultrastructure, molecular phylogeny, and prevalence rates of Alternosema bostrichidis gen. nov. sp. nov. (Microsporidia, Terresporidia), a parasite of Prostephanus truncatus and Dinoderus spp. (Coleoptera, Bostrichidae).

A new species and a new genus of a microsporidium Alternosema bostrichidis isolated from an adult Prostephanus truncatus in Mexico and from three species of the genus Dinoderus in Nigeria are described. The microsporidium is monomorphic, monoxenic, and develops in direct contact with host cell cytoplasm. The infection first appears with thoracic muscles, followed by a generalized invasion of the host. All developmental stages are diplokaryotic. Sporogony is disporoblastic. Mature spores are ovoid. Unfixed spores measure 3.7-4.2 × 2.0-2.6 µm, fixed and stained spores 3.5-5.0 × 2.4-2.8 µm. The polaroplast consists of dense lamellae and rare lamellae. The polar tube is slightly anisofilar, consisting of 11-17 coils, with 9-14 proximal (130 nm in diameter) and 2-3 distal coils (120 nm in diameter) arranged in one layer. Molecular phylogenetic analysis based upon a short portion of small-subunit ribosomal RNA gene (Genbank accession # KP455651) placed the new microsporidium within Liebermannia-Orthosomella lineage, which contains multiple undescribed parasites. In particular, A. bostrichidis showed maximal sequence similarity of 95% to Microsporidium sp. BBRE2 (# FJ755987) from Baikalian Diplacanthus brevispinus (Amphipoda: Acanthogammaridae) and Microsporidium sp. Comp CD Van 2 (# KC111784) from compost and soil in Canada. Frequent, devastating epizootics of laboratory cultures of A. bostrichidis support its potential as a biological control agent of grain borers.

Spiroplasma leucomae sp. nov., isolated in Poland from white satin moth (Leucoma salicis L.) larvae.

Spiroplasma sp. strain SMA(T), isolated in Poland from white satin moth larvae, Leucoma salicis L. (Lepidoptera: Lymantriidae), was serologically distinct from other Spiroplasma species, groups or subgroups. Dark-field microscopy of the cells revealed the classical helical shape and subsequent transmission electron microscopy revealed cells surrounded by only a single cell membrane (lacking a cell wall). Growth of strain SMA(T) occurred in M1D medium at 30 degrees C. Strain SMA(T) catabolized both glucose and arginine, but did not hydrolyse urea. The G+C content of the DNA was 24+/-1 mol% as determined by melting temperature analysis. Serological analysis revealed a very weak cross-reactivity (positive reaction only up to a 1 : 80 dilution) with two Spiroplasma strains, 277F (Spiroplasma sp. group I-4) and LB-12 (Spiroplasma sp. group I-5). Strain SMA(T) (=ATCC BAA-521T=NBRC 100392T) is designated the type strain of a novel species, Spiroplasma leucomae sp. nov. (class Mollicutes: order Entomoplasmatales: family Spiroplasmataceae).

Molecular characterization of Agrotis segetum nucleopolyhedrovirus from Poland.

The turnip moth, Agrotis segetum (Lepidoptera, Noctuidae), is an important pest insect in Europe, Asia, and Africa. We have genetically characterized and classified a nucleopolyhedrovirus isolated from A. segetum larvae in Poland (AgseNPV-P). The restriction pattern of AgseNPV-P was distinct from an isolate from England/France (AgseNPV-UK and AgseNPV-F). Sequence analysis of three conserved baculovirus genes, polyhedrin, lef-8 and pif-2, revealed that AgseNPV-P differs substantially from the already described NPVs isolated from A. segetum and possibly represents a new NPV species. Phylogenetic analysis placed AgseNPV-P among group II NPVs and showed the closest relationship to Agrotis ipsilon (Agip) NPV and Spodoptera exigua (Se) MNPV.