Indian-Meal Moth

Adults are 8–10 millimetres (5⁄16–13⁄32 in) in length with 16–20 millimetres (5⁄8–13⁄16 in) wingspans. The distal two thirds of their forewings are generally reddish brown in color with a copper luster. They can also be bronze or dark gray. The more proximal parts of the wings are yellow-gray or white-gray, with a dark band at the intersection between the proximal and distal regions. The hindwings, in general, are uniformly gray. The eggs of the Indianmeal moth are white, ovate, and very small. It is difficult to see them with the naked eye. Newly hatched larvae are equally difficult to see. They are mostly off-white in color, have brown heads, and develop through five to seven larval instars. When these larvae mature, they measure about 12–14 millimetres (15⁄32–9⁄16 in) long. Larvae also have three sets of legs near the head and five sets of prolegs protruding from the abdomen. The legs help the larvae move over long distances in order to find pupation sites.

Plodia interpunctella is found on every continent in tropical habitats, excluding Antarctica. Within the United States, the moth is most commonly found in Florida, where it thrives in the tropical habitat. The moth lives in a wide range of conditions, making it a persistent pest. It is often found at food storage facilities worldwide, specifically in grain bins or grain storage buildings.

Moths feed on many plant-based foods including dry pet food (plant based), birdseed, cereal, soup mixes, bread, pasta, rice, flour, spices, dried fruits and nuts. There is strong evidence that the northern Manitoba wheat supports the development of the moth. Other optimal diets include sultanas, American yellow corn and almonds. Groundnuts and maize meal, on the other hand, result in a longer development time for the moths.

The Indianmeal moth is the only known living species of the genus Plodia. It is closely related to the genera Cadra and Ephestia, which include other pest species like E. kuehniella, also known as the "flour moth". The species has been described under a number of junior synonyms, which may occasionally still be found in non-entomological sources.

Ephestia glycinivora Matsumura, 1917 Ephestia glycinivorella Matsumura, 1932 (unjustified emendation) Plodia castaneella (Reutti, 1898) Plodia glycinivora (Matsumura, 1917) Plodia interpunctalis (Hübner, 1825) Plodia latercula (Hampson, 1901) Plodia zeae (Fitch, 1856) Tinea castaneella Reutti, 1898 Tinea interpunctalis Hübner, 1825 Tinea interpunctella Hübner, [1813] Tinea zeae Fitch, 1856 Unadilla latercula Hampson, 1901 The common name, "Indianmeal moth", for this species was coined by Asa Fitch, an entomologist employed by the state of New York in the 19th century. In a report published in 1856, Fitch discussed the species, noting that the larvae had been observed to infest stores of cornmeal, which at the time was referred to as "Indian meal".