Tropical warehouse moth
The almond moth or tropical warehouse moth (Cadra cautella) is a small, stored-product pest. Almond moths infest flour, bran, oats, and other grains, as well as dried fruits. It belongs to the family of snout moths (Pyralidae), and more specifically to the tribe Phycitini of the huge snout moth subfamily Phycitinae. This species may be confused with the related Indian mealmoth (Plodia interpunctella) or the Mediterranean flour moth (Ephestia kuehniella), which are also common pantry pests in the same subfamily.
Other common names, particularly in nonbiological literature, are dried currant moth and fig moth, which invite confusion with the close relatives Cadra figulilella (raisin moth) and Cadra calidella (dried fruit moth). Like the raisin moth, the almond moth has achieved an essentially cosmopolitan distribution due to inadvertent transport with food products in its larval form. Adults live for about 10 days after eclosion and do not eat, but may drink if water is available. The mating system is polygamous; however, many females will only mate once.
Adult almond months are predominantly light brown in color, with smaller hind wings that are typically gray. When extended, its wingspan ranges from 14 to 22 mm. The back edges of the wings are lined with a short fringe.
Almond moth larvae are mostly gray with darker heads. The caterpillar is 12–15 mm long and identifiable by the pattern of spots along its back.
Almond moths are found around the world. Although it thrives best in tropical climates, it has spread to many regions around the globe due to its tendency to infest dry goods that are shipped internationally. For example, it has been transported across Polynesia with copra shipments.
As almond moths exists primarily as a pest, its habitat is often some kind of dry food product which is stored in a warehouse or similar industrial environment. Most commonly, they are found in dried fruits, but they have also been found in nuts, beans, flour, and other grains.
Almond moths are largely polygynous; most males will remate multiple times, but only around 20% of females will remate. Although the amount of sperm produced by males decreases across subsequent copulations, this appears to have no effect on the number of eggs laid and offspring hatched by the female. However, larger spermatophores are correlated with several outcomes that benefit male moths. First, a large spermatophore decreases the likelihood that the recipient female will remate, and if she does, a large spermatophore ensures a better chance of paternity for the first male moth. Mating decreases lifespan for both male and female moths relative to virgins.
The almond moth thrives best in warm, humid environments. The ideal temperature range for development is 30–32 degrees Celsius (86–90 degrees Fahrenheit), and the ideal humidity range is 70-80%. In optimal conditions, it takes about three and a half days for eggs to hatch, and the larvae go through five instars over a period ranging from 17 to 37 days. The pupal stages lasts around seven days in optimal temperature and humidity. Adult females live on average for ten days and adult males live for an average of six to seven days.
The almond moth is commonly regarded as a pest because it can be found in various kinds of dry food products including, but not limited to: dried fruits, wheat products, flours, nuts, and seeds. A variety of means by which to control the spread of almond moths have been explored. While pesticides and other chemical agents may reduce infestation, these products can present harmful consequences for the environment and for the humans who consume the foods on which the almond moth feeds. Thus, the exploration of natural enemies of the almond moth (including various kinds of predators and parasites) has been pursued as a means to control infestations.
