The Terfeziaceae, or desert truffles, is a family of truffles (Arabic: كمأ Kamā') endemic to arid and semi-arid areas of the Mediterranean Region, North Africa, and the Middle East. This group consists of three genera: Terfezia, Tirmania, and Mattirolomyces. They are a few centimetres across and weigh from 30 to 300 grams (1-10 oz). Desert truffles are often used as a culinary ingredient.

Desert truffles, as the name suggests, predominantly grow in the desert. They have been found in arid and semi-arid zones of the Kalahari desert, the Mediterranean basin, Syria, Iran, Iraq, Kuwait, the Negev desert in Palestine, the Sahara, Saudi Arabia, Qatar, Libya, Spain, Greece, Cyprus, Hungary, Croatia, It is commonly said that they are formed where lightning strikes the desert sands, since they are not the most common of fungi (thus justifying their cost).

Desert truffles do not have the same flavor as European truffles, but tend to be more common and thus more affordable. Forest truffles (Tuber genus) typically cost $1000 per kilogram, and Italian truffles may sell for up to $2200 per kilogram, while Terfezia truffles sold as of 2002 in Riyadh for $80 to $105 a kilo, and in recent years have reached, but not yet exceeded, $270.

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