What Is It?

• As a larva, I cling to the trees ...
• ...with bristles at the ends of my “toes.”
• I look like bird poop when young.
• Then become a great beauty when grown.

Giant swallowtail caterpillars look like blobs of bird poop. This helps them avoid predators. The caterpillar body appears to have many legs, but only the three pairs near the head are true legs. The rest look like toes but are bristly prolegs. These help the caterpillar cling to the branches of host trees like prickly ash. Adult giant swallowtails are Missouri’s largest butterflies, with a wingspan of 3 to 5 inches. Learn more at mdc.mo.gov/field-guide.