The larvae are found in dead and dying twigs and branches, and frequently in 
polypore fungi. Tropideres fasciatus (Olivier) larvae have been found in fungi 
associated with dead sycamore. The adults have been found on sassafras and birch. 
T. dorsalis (Thunberg) occurs in dead hemlock. Choragus zimmermanni LeConte 
has been found in fungi on dead maple and oak. The larvae of this species 
overwinter in the wood (23, 1/227). 
Family Brentidae 
Brentid Beetles 
This family is composed of mostly tropical species. The snout of these weevils is 
straight and projects directly forward. The antennae are not elbowed. The thorax is 
longer than wide. The oak timberworm, Arrhenodes minutus (Drury), 1s the only 
tree-infesting species that occurs in the Eastern United States. It breeds chiefly in 
oak, beech, and poplar, and its life cycle usually requires 3 years. 
Adults are dark reddish-brown with yellowish spots or bars on the elytra. They 
vary greatly in length: males may be from 7 to 35 mm long and females may be up 
to 25 mm long. The snout of the female is straight, narrow, and much longer than 
the head; that of the male is short and broad with large mandibles (fig. 146). The 
larva of this species is an exception to the legless condition usually found among 
weevils. Timberworm larvae have vestigial two-jointed legs. 
F-519917 
Figure 146.—Adults of the oak timberworm, Arrhenodes 
minutus. Male on left; female on right. 
Adults are active from May through August. Both sexes are attracted to fresh 
wounds, and females lay their eggs in the tissue around wounds. Although most 
females lay their eggs on living trees, occasionally eggs are laid on dead trees, but 
always in wounds made before the trees died. The larvae bore through the wood, 
constructing galleries in all directions. The larval galleries cause serious degrade of 
infested trees. Occasionally much of the timber in a stand is so badly damaged that 
it is unfit for cooperage (/69). 
Family Nemonychidae 
Pine-Flower Weevils 
This small family is represented in the West by the genus Diodyrhynchus and in 
the East by the genus Cimberis. These weevils are characterized by having a 
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