DR. JOHN BRACKENBURY / SCIENCE PHOTO LIBRARY DR. JOHN BRACKENBURY / SCIENCE PHOTO LIBRARY
Dusky birch sawfly larvae (Croesus latitarsus) in defence positions. These larvae assume this c- shaped posture when disturbed. They are the juvenile form of the dusky birch sawfly, an insect that is similar to wasps but lacks a waist-like constriction at the front of its abdomen. These larvae are pests of many birch trees, causing defoliation. They look similar to the caterpillars of moths and butterflies, but can be distinguished from them by the number of short prolegs (light green) on the abdomen. Caterpillars possess between 2 and 5 pairs of prolegs, whereas sawfly larvae always have 6 or more.
Model release not required. Property release not required.