Pleopodal lungs
Pleopodal lungs are an anatomical feature of terrestrial isopods and a component of their respiratory system. They are ancestrally derived from pleopodal gills, and they facilitate gas exchange on land. They perform a similar function as spiracles do in insects.

Pleopodal lungs are identifiable on woodlice as white patches on the lower 5 segments (the pleon) on the ventral side (underside). The number of pleopodal lungs vary by species – they may have up to five pairs, or only two pairs as in "Porcellio laevis;" a minority of species lack pleopodal lungs entirely. 
Q206338
isopods
Concept
Q7891
respiratory system
Concept
None
gills
UNK
Q1146120
gas exchange
Concept
Q31060267
spiracles
Concept
Q216191
woodlice
Concept
None
pleon
UNK
Q2741575
Porcellio laevis
Concept
Q68706853
Pleopodal lungs
Concept
Q68706853
Pleopodal lungs
Concept
+5^^http://www.w3.org/2001/XMLSchema#decimal
5
NUMBER
found in taxon