Discover Nature NotesMore posts

The Swallowtails’ Tale

Apr 18, 2016

In nature no insect is quite like the swallowtail.

Swallowtail butterflies have extensions on their hind wings that resemble the tail of a swallow. This feature makes swallowtails an easy group of butterflies to recognize.

Swallowtails are big butterflies with wingspans from two to nearly six inches. Some of these butterflies are easy to identify, too. The swallowtails with bold black-and-white stripes are tiger swallowtails. And the black swallowtails… are black swallowtails.

Swallowtail caterpillars are distinct from one another, and their appearance helps protect them from predators. Giant swallowtail caterpillars are dark with irregular white markings. They resemble bird droppings–a mimicry that puts off would-be predators. The tiger swallowtail and spicebush swallowtail caterpillars have large eyespots toward the rear of their bodies. These eyespots divert predators from the insect’s head. A spicebush swallowtail larva will also curl a leaf, wrap up in it, secure it with a strand of silk, and hide in its makeshift shelter.

All true swallowtail caterpillars have a unique defense: Each has a Y-shaped gland on its body that can emit a foul odor when the insect is disturbed.

Spotlight on the Spicebush Swallowtail

The spicebush swallowtail is a  blackish swallowtail with iridescent blue (females) or green (males) on the hindwings
  • The larvae of the spicebush are bright green, smooth, with a prominent pair of black and yellow eyespots on a hump behind the actual head, and two more yellow spots behind those.
  • There are 3 broods, with adults flying from April into October. Larvae hide in shelters made by spinning silk onto the surface of a leaf of the food plant, causing the leaf to curl around them.
    Larvae eat sassafras and spicebush, making a folded-over “tent” out of a leaf of the food plant to conceal itself when not feeding. Adults drink nectar from many flowers, but especially from butterfly weed.
  • The spicebush swallowtail is a common breeding resident in the State of Missouri.

Discover more about all swallowtail species with the MDC’s Field Guide.

Recent Posts

white-lined sphinx larva

Mysteries of the Sphinx Moths

Sep 08, 2019

They rest like a sphinx, hover like a hummingbird, flutter like a bat, and are built for speed like a plane.  Sphinx moths have an identity crisis.  With us, not them.  Many are mistaken for other species. Discover more in this week's Discover Nature Notes.

Common Nighthawk

Flying Bullbats

Sep 02, 2019

Watch for creatures known as flying "bullbats" in Missouri's September skies. Common Nighthawks fly like bats and make booming dives at dawn and dusk on their southern migration. Hear what they sound like and why their name makes no sense in this week's Discover Nature Note.

Niangua Darter

The Hummingbirds of the Fish World

Aug 25, 2019

Darters have been called the hummingbirds of the fish world. See their flash-and-dash, and travel streamside to discover the Niangua darter, a fish found only in Missouri, in this week's Discover Nature Note.

Field Guide

Discovering nature from A-Z is one click away


You had fun hunting, catching or gathering your quarry—now have more fun cooking and eating it.
Check out the recipes