FAMILY DERODONTIDAE 
Derodontid adults are small brown or dullish-brown beetles 
about 2 to 6 mm. long. Only about one-half dozen species have 
been recorded from the United States. 
Laricobius erichsonw Rosenh., 2 predator of the balsam woolly 
aphid, has been imported from Europe during recent years and 
released in aphid intested stands of fr in Canada, New England, 
North Carolina, and the Pacific Northwest. The adult is an elong- 
ate oval beetle about 2.2 to 2.4 mm. long. The body is covered with 
yellowish to brownish to black hairs; the head is usually hidden 
from above; and the central portions of the elytra, the antennae, 
and the legs are reddish brown. The larvae are covered with flakes 
of the aphid’s wool and small bits of bark. 
Eggs are deposited deep within aphid egg clusters or under 
lichens on the bark. The larvae feed on the host eggs until full- 
grown at which time they drop to the ground and pupate in 
cocoons of compacted soil particles. Adults are active on warm, 
sunny days (113). 
FAMILY CUCUJIDAE 
FLAT BARK BEETLES 
Members of this family are rather small and extremely fiat, 
yellowish, brownish, reddish, or black beetles. The larvae, also 
often very flat, are usually found under the bark of unhealthy 
trees or newly-felled trees and logs. The majority are scavengers, 
but a few are parasitic or predacious on mites, small insects, 
wood boring larvae, or Hymenoptera. 
Catogenus rufus (Fab.) is a common eastern parasite of borers 
in sugar maple. Adults are elongate, reddish brown and up to 12 
mm. long. The larvae are soft-bodied and white, with recurved 
hooks on the ninth abdominal segment. They are usually found 
beneath the bark in the pupal cells of their host. Cucujus clavipes 
F. is another conspicuous eastern species. The adult is bright red, 
exceedingly flat, and about 10 to 14 mm. long. The larvae are 
usually found under the bark of recently dead trees, especially 
ash and poplar. 
FAMILY COLYDIIDAE 
This family consists of small, elongate, slender beetles rarely 
over 5 mm. long. They are reddish brown to nearly black and 
beautifully sculptured. The larvae of certain species, some of 
which are found under bark in association with bark beetles, are 
scavengers. Others, such as those of Nematidium filiforme LeC., 
Bitoma carinata (LeC.), and Colydium lineola Say, feed on the 
larvae of ambrosia beetles, cossonids, and certain other borers in 
their tunnels. 
FAMILY MELANDRYIDAE 
Adults of this family are small to large, usually elongate to 
oval, loosely jointed beetles. The thorax is margined at the sides; 
the antennae are filiform; the front coxal cavities are open be- 
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