- Subfamily: Pyralinae, Pyralini
- Wingspan: 19-32 mm
- Flight period: Jun - Aug
- Spread: Common
- Host plants: Stocked wheat and derivatives
The Pyralis farinalis also called Meal Moth is a moth of the Pyralidae family, with a wingspan of 19-32 mm.
It is widespread throughout Europe with the exception of Iceland and Ukraine. *
Its range extends to all continents except Antarctica. In Italy it is also present in the islands. *
The front wings of the Pyralis farinalis have the front wing divided into three parts by white lines with a wavy pattern. The proximal and distal bands are brown, while the mesdian bands are light brown / ocher. The area near the inner corner has black dusting. **
Also the rear wing is divided in three bands with wavy white lines, they are white / yellowish finely dusted with black that near the edge they are more intense creating the appearance of line and spots. All wings are fringed.
The head is brown / ocher, the thorax is brown, the abdomen is brown / ocher with brown dusting.
Often, when at rest, adult moths keep the tip of their abdomen at 90 ° to the rest of the body. The adults do not live long after mating and the eggs hatch quickly, which leads to Pyralis farinalis to have a rapid life cycle and to have several generations in a single year.
The Pyralis farinalis is a species that is well suited to human coexistence and the resulting urbanization. It is typically found in silos or other grain storage buildings where grain is poorly stored and moisture is able to infiltrate the grain supply. although it generally prefers to live among the debris. ***
The larvae spend most of their time hidden in silky tunnels covered in flour and debris that keep them safe from predators. To feed, they lean out of the openings of these tunnels. The whitish ellipsoidal eggs, very wrinkled with folds running lengthwise along the egg. ****
The larva is translucent white / yellowish in color with head and prothoracic shield of amber color, small black tubercles, from which few hairs come out. **
The chrysalis is yellow / orange, with brown / amber shades.
Pyralis farinalis is a moth that infests stored wheat and soy derivatives. It also feeds on other types of grains and vegetables, such as potatoes. The flour moth larvae are also interesting because they feed on all of them parts of the wheat plant and seem to have no preference for one part of the other. The larvae are equally likely to eat the seed, bran, husk or straw of a cereal plant. *****
* Lepidoptera mundi https://lepidoptera.eu/ - Fauna Europea https://fauna-eu.org/
** Bestimmungshilfe für die in Europa nachgewiesenen Schmetterlingsarten - http://lepiforum.de/ -
*** Landolt, P. J.; Curtis, C. E. (1982). "Interspecific Sexual Attraction between Pyralis farinalis L. and Amyelois transitella (Walker) (Lepidoptera: Pyralidae)". Journal of the Kansas Entomological Society. 55 (2): 248–252. - https://www.jstor.org/stable/25084280
**** Arbogast, Richard T.; Van Byrd, Richard (1981-01-01). "External morphology of the eggs of the meal moth, Pyralis farinalis (L.), and the murky meal moth, Aglossa caprealis (Hübner) (Lepidoptera: Pyralidae)". International Journal of Insect Morphology and Embryology - https://www.sciencedirect.com/science/article/abs/pii/0020732281900222?via%3Dihub
***** Howard, Leland Ossian; Marlatt, C. L. (1896). - https://books.google.it/books?id=6oIoAAAAYAAJ&pg=PA7&redir_esc=y#v=onepage&q&f=false