A MONA number (short for Moths of North America), or Hodges number after Ronald W. Hodges, is part of a numbering system for North American moths found north of Mexico in the Continental United States and Canada, as well as the island of Greenland. Introduced in 1983 by Hodges through the publication of Check List of the Lepidoptera of America North of Mexico, the system began an ongoing numeration process in order to compile a list of the over 12,000 moths of North America north of Mexico. The system numbers moths within the same family close together for identification purposes. For example, the species Epimartyria auricrinella begins the numbering system at 0001 while Epimartyria pardella is numbered 0002.