All Natural Breakfast

Indian-meal moth of winter - 9mm     REK

Last month I saw the first flying insect of winter on the creek house bathroom wall.  It was 9mm long and I readily identified it on INaturalist as an Indian-meal moth, Plodia interpunctella.  It occurs on all the continents and is named because it is commonly found in Indian meal, i.e. corn meal.  It is considered the most important pest in stored food products in America and is omnivorous, consuming grain products, seeds, dried fruit, dog food, and spices. (Florida University Entomology)

Intact pupa

The next week I started to pour some crunchy cereal into my bowl for breakfast when I saw something roll out of the bag.  When I was a child in the 1950's breakfast cereals advertised "a toy in every box!"  Now 68 years later this "toy" was "organic" just like the cereal.  It was a well formed 7mm pupa with the future wings visible along the back.

Empty pupa case on a toothpick for scale - REK

We hadn't opened that cereal box for several months, the plastic bag inside was rolled up tight and it was stored in a plastic box with snap on lid. After breakfast I noticed several things clinging to the inside of the clear plastic bag.  These were empty pupa cases the same size as the moth, attached by silk to the clear plastic cereal bag. I picked this one up on a toothpick for photos.

Cereal flake with larvae and lots of frass - REK

After emptying the bag on a plate I sorted through the breakfast cereal with a magnifier. Six of the flakes were packed with extra organic nutrition, not too bad for a nearly full box. Tiny 3mm larvae clinging to them as well as little white eggs and a lot of frass.   Just think, the whole life cycle present in our kitchen!
According to the National Pesticide Information Center (NPIC), the larvae travel away from the food source to pupate, increasing their chances of survival.  They are able to chew their way through plastic and cardboard boxes, probably how they were able to attack our cereal.  The site has an extensive list of foods they can attack including cereal, grains, beans, nuts, flour, dried fruit, birdseed, dry animal food, spices, tea, chocolate, and candies.

If by now you  are getting a little paranoid,  the NPIC also has an extensive list of Control Tips that could keep you busy for a week.  I for one will be eating my cereal a lot faster and maybe not look at it under magnification quite so often.

For more details, try Tardigrade.net 

If you haven't had enough fun yet, you may want to read Bug Eric's suggestions for an indoor bug hunt.