Acarus siro

Definition

A cosmopolitan species of astigmatid mite (family Acaridae) that infests stored grain, flour, animal feed, and cheese, causing direct damage to commodities and acting as a vector for fungal pathogens and spoilage organisms. Adults are minute (approximately 0.3–0.4 mm), pale, and slow-moving, with populations capable of explosive growth under warm, humid conditions. The species is a significant pest in food storage and agriculture, and heavy infestations can cause allergic reactions and dermatitis in handlers (grocers' itch). Formerly placed in Tyroglyphus as T. farinae.

Etymology

From Latin Acarus (mite, tick) + siro (possibly from Greek seirō, to draw tight, or an arbitrary specific epithet)

Example

In grain elevators, Acarus siro populations exceeding 10,000 individuals per kilogram can reduce wheat germination, cause heating in stored bulk, and contaminate flour with allergenic detritus that triggers respiratory sensitivity in mill workers.

Synonyms

• Tyroglyphus farinae

Related Terms

• stored-product pest
• grain mite
• Astigmata
• acarology
• dermatitis
• grocers' itch
• Tyrophagus putrescentiae
• Lepidoglyphus destructor

Usage Notes

The name flour mite is sometimes applied loosely to several Acaridae species; precise identification requires microscopic examination. Acarus siro is distinguished from the mold mite Tyrophagus putrescentiae by slower movement and preference for drier substrates. The obsolete synonym Tyroglyphus farinae persists in older agricultural literature and should be cross-referenced in historical pest-management records.