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The antennal sensilla of the brown spruce longhorn beetle, Tetropium fuscum (Fabr.) (Coleoptera: Cerambycidae) were examined with particular focus on the sensilla present on the apical flagellomere. T. fuscum antennae are composed of 11 segments, namely the scape, pedicel, and nine flagellomeres. Nine types of sensilla were observed: three types of sensilla chaetica, sensilla trichodea, two types of sensilla basiconica, grooved peg sensilla, thick-walled sensilla, and Böhm bristles. Seven of these types were present on the apical flagellomere, the exceptions were sensilla chaetica type 3 and Böhm bristles. There were no significant differences in the distribution or density of sensilla present on the ninth flagellomere of males and females, except that males had significantly more sensilla chaetica type 1, which are put forward as the putative contact chemoreceptors for T. fuscum.

We describe the calling posture of the brown spruce longhorn beetle, Tetropium fuscum (F.), and demonstrate, using solid-phase micro-extraction and gas chromatography – mass spectrometry, that this posture is positively correlated with the release of fuscumol, a male-produced long-range pheromone. The posture is observed only in males and is characterized by an extension of the legs that raises the body entirely off the substrate at an angle of approximately 10°, with the posterior end higher than the head. Characterization of the calling posture is a useful diagnostic tool for future research on the reproductive biology of T. fuscum, since a simple visual assessment can be used instead of chemical analysis to determine when males are emitting fuscumol. In addition, we demonstrate that the presence of conspecific males stimulates calling behaviour in T. fuscum. This study contributes much-needed data on the biology and mating behavior of this invasive wood-boring species.

The brown spruce longhorn beetle (BSLB), Tetropium fuscum (Fabr.), is native to Europe but has recently been discovered in Halifax, Nova Scotia, where efforts are underway to eradicate it. If attempts to eradicate this beetle are unsuccessful, phytosanitary measures will have to be developed to ensure continued access to markets. We carried out studies to determine the lethal temperatures for different BSLB life stages in spruce. The beetles were exposed to different temperatures for various time periods in lumber of low and high moisture content. Adults died after 30 and 15 minutes exposure to 40 and 45°C, respectively, and pupae died after 30 minutes exposure to 45°C. Larvae required exposure to 50°C for 30 minutes (or 55°C for 15 minutes) to ensure 100% mortality. Larval survival was slightly higher in wood with low moisture content. The study was repeated a second year for the 50°C/30-minute and 55°C/15-minute treatments for larvae and the 45°C/30-minute for pupae at very low moisture (12-15% oven-dry basis) content, with similar results. Our results demonstrate that heat treatment is an effective phytosanitary method to ensure that wood does not contain any live BSLB.Current phytosanitary guidelines listed by the Canadian Food Inspection Agency in its directive "Canadian Heat-treated Wood Products Certification Program (CHTWPCP) for Export" (56ºC, 30 minutes) are more than adequate to ensure BSLB-free wood. Key words: brown spruce longhorn beetle, heat treatment, hygrothermal stress, Tetropium fuscum, wood borers

The first confirmed presence in North America of the palearctic cerambycid, Tetropium fuscum (Fabr.) (the brown spruce longhorn beetle) is reported. It was discovered attacking red spruce, Picea rubens Sarg., at Point Pleasant Park in the port city of Halifax, Nova Scotia. Biological notes pertinent to its infestation of red spruce at the Park are presented. In response to the observed tree mortality, bolts from living trees with green crowns and excessive resin flow have been reared repeatedly since 1999 with consistent results: emergence of Tetropium fuscum. Research on the North American establishment of this species has yielded novel information.