primitive insect belonging to any of three families in the suborder Symphyta (order Hymenoptera): Xiphydriidae, Orussidae (sometimes spelled Oryssidae), and Anaxyelidae. Orussidae are known as parasitic wood wasps; Anaxyelidae are known as cedar wood wasps. Xiphydriids, found in Europe and North America, are about 20 to 25 mm (about 0.8 to 1 inch) long, cylindrical in shape, and blackish in colour. The larvae bore into the wood of dead or dying deciduous trees.
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