An overview is presented of the progress made on the taxonomy, classification and phylogeny of weevils in the 250 years since the first taxonomic descriptions of weevils by Carolus Linnaeus. The number of described weevils species is calculated to be about 62 000 and the likely total number of existing species 220 000, indicating that we have described just over a quarter of the diversity of this important group of beetles and that, at current rates of discovery and description, it will take another 650 years or so to describe the rest. Within the framework of the current concept of weevil phylogeny, a brief account is given of the seven main weevil lineages (families), and of the subfamilies of the largest of them, the Curculionidae, summarising their diversity, distribution and biology and identifying the major classificatory problems remaining in each. In conjunction with the phylogenetic hypothesis of weevil relationships and their fossil record, which is briefly summarised, the evolutionary history of weevils is mapped as a sequence of key evolutionary innovations that together have led to the phenomenal diversification and success of weevils.

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Resource partitioning in the silphid fauna of southern Ontario is examined in detail, using baited pitfall traps placed in four different habitats. During 1979 and 1980, a total of 9549 specimens of Silphidae were collected, representing 12 species, of which 5 were in the subfamily Silphinae and 7 in the subfamily Nicrophorinae. The roles of different seasonal patterns, habitat specificity, and food type and size in resource partitioning are discussed for all species. At the subfamilial level, resource partitioning is accomplished through selection of different sizes of carcasses, while at the specific level, seasonal patterns and habitat specificity appear to be the primary means permitting coexistence.In the Silphidae, competition for food resources appears to be the primary factor inducing ecological character displacement. The possible origins of patterns of resource use in this assemblage are discussed in an ecological and geological time framework.

The pupae of Otiorhynchus (Arammichnus) dieckmanni Magnano, 1979, O. (s.str.) tenebricosus (Herbst, 1784) form lugdunensis Boheman, 1843, Peritelus sphaeroides Germar, 1824, Strophosoma (Neliocarus) c.f. sus Stephens, 1831 and Tanymecus (s. str.) palliatus (Fabricius, 1787) are described and illustrated for the first time. The pupae of Barypeithes (Exomias) pellucidus (Boheman, 1834), Brachyderes (s. str.) incanus (Linnaeus, 1758), Liophloeus (s. str.) tessulatus (Müller, 1776), Phyllobius intrusus Kôno, 1948 (= Parascythopus exsulans Heijerman & Magnano , 2000) and Phyllobius (s. str.) pyri (Linnaeus, 1758) are redescribed and illustrated. Characteristic features including chaetotaxy, habitus and measurements are given. Pupae of the genera Peritelus, Strophosoma, and Tanymecus are described for the first time. Keys to the pupae of 14 genera of broad-nosed weevils, and to several species of Phyllobius and Otiorhynchus are also presented.

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Phylogenetic relationships among the genera of the subfamily Oxycoryninae and other belids (Curculionoidea) were reconstructed by cladistic analysis using 21 terminals and 98 characters: 62 from imaginal morphology, 33 from larval morphology and three biological characters relating to host plants and larval feeding habits. Terminal taxa represent all extant genera of Oxycoryninae, two genera of each of the three tribes of Belinae plus two outgroup taxa used to root the tree. New information on the larvae and biology of the metrioxenines is used in phylogenetic reconstruction. In accord with the single optimal cladogram obtained, a revised classification of the Oxycoryninae is proposed. The subfamily is classified into three tribes (Oxycorynini, Metrioxenini and Aglycyderini), with the tribe Oxycorynini further classified into three subtribes (Oxycraspedina Marvaldi & Oberprieler, subtr. nov., Oxycorynina and Allocorynina) and the tribe Metrioxenini into two subtribes (Metrioxenina and Afrocorynina ( = Hispodini, syn. nov.)). Larval and adult unambiguous synapomorphies defining each clade are identified. Tracing the evolution of biological traits from the phylogenetic estimate indicates that drastic shifts to phylogenetically distant host plants occurred from the ancestral belid association with conifers. Structural, chemical and/or ecological similarities of the plant organs consumed apparently had a major influence in the colonisation of different plant taxa by this group of weevils.

The goal of this study was to determine how enteric viruses persist within shellfish tissues. Several lines of novel evidence show that phagocytic blood cells (hemocytes) of Eastern oysters (Crassostrea virginica) play an important role in the retention of virus particles. Our results demonstrated an association of virus contamination with hemocytes but not with hemolymph. Live oysters contaminated overnight with hepatitis A virus (HAV) and murine norovirus (MNV) had 56% and 80% of extractable virus associated with hemocytes, respectively. Transfer of HAV-contaminated hemocytes to naïve (virus-free) oysters resulted in naïve oyster meat testing HAV positive for up to 3 weeks. Acid tolerance of HAV, MNV, poliovirus (PV), and feline calicivirus (FCV) correlated with the ability of each virus to persist within oysters. Using reverse transcription-PCR (RT-PCR) to evaluate persistence of these viruses in oysters, we showed that HAV persisted the longest (>21 days) and was most acid resistant, MNV and PV were less tolerant of acidic pH, persisting for up to 12 days and 1 day, respectively, and FCV did not persist (<1 day) within oysters and was not acid tolerant. This suggests that the ability of a virus to tolerate the acidic conditions typical of phagolysosomal vesicles within hemocytes plays a role in determining virus persistence in shellfish. Evaluating oyster and hemocyte homogenates and live contaminated oysters as a prelude to developing improved viral RNA extraction methods, we found that viruses were extracted more expediently from hemocytes than from whole shellfish tissues and gave similar RT-PCR detection sensitivities.

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