Despite the coincidence, the Indigo Stem Borer did not get its name from the purple-toned band at the bottom of its wings.
Most people know the color indigo from the 'roygbiv' acronym that children learn to help remember a rainbow's color order. The source of the color's name actually comes from a plant. Wild indigo grows in natural areas and is also found in gardens. Its purple-blue flowers can create a purple dye used to color fabric, and its sap turns purple when exposed to air. The caterpillars of the Idigo Stem Borer feed on this plant, but they do not turn purple from it. The caterpillar is actually brown, much like its adult form. It digs into the stem of the plant and eats its way through it, boring a tunnel as it moves. The caterpillar's plant host and feeding behavior are how the moth got its common name.
Moths are brown with a series of white markings that help differentiate them from other borer moths. This species has a single white dot by the base of the wings, near the 'shoulders'. An angled trio of white spots tuck under a dark band. On the lower half of the wings, a cluster of white spots resemble an oval-shaped egg that was cracked in many places, exposing a golden-orange middle. At the lower edge of the wings sits a dark band of color with purple tones. Orange patches are seen in the middle of the wings and at the tips. This moth flies later in the year, at the end of summer and into autumn. Look for it near woodlands, fields, and swampy areas where wild indigo, American angelica, dogbane, and Indian plantain grow.
Scientific Name: Papaipema baptisiae
Butterfly or Moth
Size (Adult; Length): 19mm to 20mm (0.74in to 0.78in)
Colors: brown; white; purple; orange
Descriptors: lilac band; purple bottom; cracked egg; trio; three white spots; hairy; orange spots; small white dot; flying
Note: An insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above as they are driven by environmental factors (such as climate change), available food supplies and mating patterns. Grayed-out selections indicate that the subject in question has not been reported in that particular territory. U.S. states and Canadian provinces / territories are clickable to their respective bug listings.
Butterfly and Moth Anatomy
Antennae: Butterflies and Moths have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and proboscis.
Thorax: Home to the three pairs of legs as well as vital internal organs.
Abdomen: Contains vital internal organs such as the heart(s) and reproduction facilities.
Forewing: The upper, forward wing pair used for flying.
Hindwing: The lower, rearward wing pair used for flying.
NOTE: Butterflies and Moths are part of the Lepidopteran order as they share many similarities.