Flour mite

{{Short description|Species of mite}}

{{Speciesbox

| image= Grain mite 1.JPG

| taxon = Acarus siro

| authority = Linnaeus, 1758

}}

The flour mite, Acarus siro, a pest of stored grains and animal feedstuffs,{{cite journal |author1=J. A. Dunn |author2=B. B. Thind |author3=C. Danks |author4=J. Chambers |title=Rapid method for the detection of storage mites in cereals: feasibility of an ELISA based approach |journal=Bulletin of Entomological Research |volume=98 |issue=2 |pages=207–213 |date=April 2008 |pmid=18279566 |doi=10.1017/S0007485308005634 }}{{cite journal |author1=L. M. I. Webster |author2=R. H. Thomas |author3=G. P. McCormack |year=2004 |title=Molecular systematics of Acarus si s. lat., a complex of stored food pests |journal=Molecular Phylogenetics and Evolution |volume=32 |issue=3 |pages=817–822 |doi=10.1016/j.ympev.2004.04.005|pmid=15288058 }} is one of many species of grain and flour mites.{{cite book|author=Jerome Goddard|title=Physician's guide to arthropods of medical importance|url=https://books.google.com/books?id=rWMeblT89DUC&pg=PA248|accessdate=14 April 2010|date=30 March 2007|publisher=CRC Press|isbn=978-0-8493-8539-1|pages=248–}} An older name for the species is Tyroglyphus farinae.{{cite journal|author=International Rice Research Institute|title=IRRN|journal=International Rice Research Notes|url=https://archive.org/details/bub_gb_5K9wN3g5AcsC|accessdate=14 April 2010|date=1 January 1989|publisher=IRRI|pages=[https://archive.org/details/bub_gb_5K9wN3g5AcsC/page/n38 39]–|issn=0115-0944}}

The flour mite, which is pale greyish white in colour with pink legs, is the most common species of mite in foodstuffs. The males are from {{convert|0.33|-|0.43|mm}} long and the female is from {{convert|0.36|-|0.66|mm|abbr=on}} long. The flour mites are found in grain and may become exceedingly abundant in poorly stored material. The female produces large clutches of eggs and the life cycle takes just over two weeks. The cast skins and dead bodies can form a fluffy brown material that accumulates under sacks on the warehouse floor. After a while, predatory mites tend to move in, and these keep the flour mites under control.{{cite book|title=Stored-grain Pests|url=https://books.google.com/books?id=HVQhqHzP0SwC&pg=PA41|year=1955|publisher=U.S. Government Printing Office|pages=41–42}}

Flour mites that contaminate grains, flour and animal feedstuffs, create allergens in the dust produced, and also transfer pathogenic microorganisms. Foodstuffs acquire a sickly sweet smell and an unpalatable taste. When fed infested feeds, animals show reduced feed intake, diarrhea, inflammation of the small intestine, and impaired growth. Pigs have their live-weight gain, feed-to-gain ratio, and nitrogen retention markedly reduced by infested feeds.{{cite journal |author=Braude, R. |author2=Low, A.G. |author3=Mitchell, K.G. |author4=Pittman, R.J. |author5=Wilkin, D.R. |year=1980 |title=Effect of flour mite infestation (Acarus siro L.) on nutritive value of pig diets. |journal=Veterinary Record |volume=106 |issue=2 |pages=35–36 |doi=10.1136/vr.106.2.35 |pmid=7361400 |url=https://www.cabdirect.org/cabdirect/abstract/19800570519 |url-access=subscription }}

Flour mites are intentionally inoculated into Mimolette cheese to improve the flavor.{{cite journal |first1 = J.P. |last1 = Melnyk |first2 = A. |last2 = Scott-Dupree |first3 = M.F. |last3 = Marcone |first4 = A. |last4 = Hill |date=August 2010 |title = Identification of cheese mite species inoculated on Mimolette and Milbenkase cheese through cryogenic scanning electron microscopy |journal = Journal of Dairy Science |volume = 93 |issue = 8 |pages = 3461–3468 |doi = 10.3168/jds.2009-2937 |pmid = 20655414 |last5 = Hill |first5 = A.|url = https://atrium.lib.uoguelph.ca/xmlui/bitstream/10214/2629/1/cheese.pdf |doi-access = free }} When used for this purpose, they may be referred to as "cheese mites".

The mites sometimes bite humans, which can cause an allergic reaction known as Baker's itch.{{cite book|author1=Robert L. Rietschel|author2=Joseph F. Fowler Jr.|title=Fisher's contact dermatitis|date=2008|publisher=BC Decker Inc.|location=Hamilton|isbn=9781550093780|page=428|edition=6th}}{{cite book|last1=Hill|first1=Dennis S.|title=Pests of Stored Foodstuffs and Their Control|date=2003|publisher=Kluwer Academic Publishers|location=Dordrecht|isbn=9780306481314|page=129}}

File:9-Acarus siro male ventr DIC40 BMOC 01-0903-003.jpg|A. siro male, adult, ventral view

File:7-Acarus siro female ventr BF20 BMOC 01-0903-003.jpg|A. siro female, adult, ventral view

File:2-Acarus siro HDN vent BF40 BMOC 86-0401-003.jpg|A. siro phoretic deutonymph, ventral view.