← Gallery II · The Orders
No. 22 · Hemimetabolous
Booklice, Barklice & Parasitic Lice
Psocodea
~11,000
Described species
~30
Families
Introduction
Modern molecular evidence merged the parasitic lice (former Phthiraptera) into Psocodea — they evolved from free-living book/bark lice ancestors.
Field marks
Key ID traits.
Combines former Psocoptera (free-living booklice/barklice) with Phthiraptera (parasitic lice on birds & mammals). Tiny, soft-bodied, wingless or with two pairs of membranous wings.
Etymology
Greek psocho 'rub small' + eidos 'form'
Wings
Variable
Diet
Detritivore · Parasitic · Blood
Habitat
Terrestrial · Parasitic
Notable examples
Booklice, barklice, head lice, body lice, pubic (crab) lice, chicken lice, dog lice.
Where to look