Decomposers
Dung beetle
dung beatles make round balls of well dung and they use this"dung" for a food scource or breeding grounds. the dung beatle can carry up to 250 times its weight
https://www.greenprophet.com/2013/01/scarab-dung-beetles-navigate-by-the-stars/
leppet-facedVultures
The Arabian Desert is the home of the leppet-faced vulture. the leppet-faced vultureis related to the torgos. This vulture is actully an old wold vulture.
http://www.birdlife.org/middle-east/news/saving-vultures-saudi-arabia
buzzards
the buzzards of the arabian desert are some of the most common birds in this desert
http://4.bp.blogspot.com/-N0lL0o4ETrA/TfMFxrLYHLI/AAAAAAAAAKE/yNRQe3jW-eQ/s1600/rsz_dsc_1627.jpg
Termites
these desert termites are the second most common decomposers in saudi arabia just under the dung beatle.
http://afghan-arabiawild.com/LongHeadTermite1cmp.jpg
Desert mushrooms
http://thedesert.wikispaces.com/file/view/desert_fungus.jpg/116209419/desert_fungus.jpg