Department of Entomology

Psocoptera (Psolids, Booklice, Barklice)

Family Fact Sheet

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Psocoptera - Brigham Young/VPI & SU PCD0330059

I. Background information

A. Origin of name

1. psoco, rub small (from gnawing habits); ptera, wing

B. Classification

1. 340 Species in U.S. and Canada

2. 28 Families in U.S. and Canada

3. 3 Suborders

a. Trogiomorpha - more than 20 antennal segments

b. Troctomorpha - 13-20 antennal segments

c. Psocomorpha - fewer than 13 antennal segments

C. Common names - psolids, booklice, barklice; old order name - Corrodentia

D. Type of metamorphosis - simple

E. Phylogenetic relationships

1. Closely related to lice

2. Earliest fossil record - Lower Permian

II. Morphological characteristics

A. 2- to 3-Segment tarsi

B. Roof-like wing position

C. No cerci

D. Overall appearance - bulbous head, long antennae

E. "Gnawing" mouthparts

III. Biological summary for the order

A. Habitat and Habits

1. Overwinter in all stages

2. Live on trunks of trees, where they feed on algae, lichens, and fungus on the bark

3. Some are household pests - grain, books, etc.; damp areas

4. Scavengers

a. Some are gregarious schools

b. webbing for some

B. Collecting and preserving

1. Collect into alcohol (BEST) or pin

2. Look for them on tree trunks, shrubs, bark, sweeps in grass; rock piles, stored grain

C. Significance

Some can carry sheep tapeworms; act as intermediate hosts