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Bug of the Week is written by "The Bug Guy," Michael J. Raupp, Professor of Entomology at the University of Maryland.

American ladies like licorice: American Lady Butterfly, Vanessa virginiensis

 

Whether upside down or right side up, the American Painted Lady is one gorgeous butterfly.

 

When not actively feeding on leaves, American Painted Lady caterpillars hide in silken shelters spun around leaves of their host plant.

Over the past several weeks we have visited some true tormentors of humankind, including floodwater mosquitoes, ticks, lanternflies, and stink bugs. This week we turn our attention to one of the real treasures of our urban wild, the enchanting American Lady butterfly, also known as the American painted lady. Last week while visiting my favorite familial B & B in Long Valley, NJ, the lady of the house asked me about some peculiar silk covering small clusters of leaves on her dainty licorice plant. Closer inspection of these silken retreats revealed a beautiful spiny caterpillar bedecked in creamy intersegmental bands with white dots on black and red bands encircling the abdominal segments - the larva of the American Lady butterfly. Awesome!

Licorice plant, Helichrysum petiolatum, belongs to the family of plants known as the Asteraceae, the sunflower family. Discriminating American Lady butterflies choose everlasting, ironweed, burdock, pussy-toes, and related species of the Asteraceae in addition to licorice plant as the food source for their young. These ladies are extreme voyagers, departing their permanent residences in the southern United States, Mexico, and Central America each year to take wing in monarch-like migrations that reach the northern United States, southern Canada, several Caribbean islands, and even Europe. Tiny eggs deposited on host plants hatch into very hungry caterpillars capable of consuming remarkable amounts of foliage as they gain more than a thousand times their birth weight during the course of development.

 

During the course of development, it is not unusual for moth and butterfly larvae like this American Painted Lady to gain more than a thousand times their birthweight.

Nestled between two leaves of licorice plant, the chrysalis sets the stage for metamorphosis from caterpillar to butterfly.

Gossamer shelters of silk spun around leaves serve as a refuge from the searching eyes of hungry predators as caterpillars feed and develop.  Transformation from larva to adult takes place in a tawny chrysalis suspended from vegetation. As you will see from the images, adult butterflies are drop-dead gorgeous. They nectar on several common hosts found in meadows and gardens including dogbane, goldenrod, marigolds, milkweeds, and vetch. In their permanent southern homes three or four generations occur annually, but in southern New England only two broods are usually observed.  Plant some pussy-toes or licorice plant and you too may be visited by these remarkable American Ladies.

Acknowledgements

Bug of the Week thanks the ever-gracious Sheri and Gordon for sharing their licorice plants and caterpillars for this story. Rebeccah Waterworth provided interesting insights into the migrations of American Ladies, and the wonderful references “Caterpillars of Eastern North America” by David Wagner and “Butterflies and Moths of North America” provided details for this episode.