Morgai flies

Vicious, biting, parasitic insects, Morgai Flies are one of the nasty nuisances of life in Mordor. They can found all over the Black Land, particularly in Gorgoroth, where they are known as Orcflies. Their sole food is blood, but enjoy feeding off nearly any beast they can find.

Relatives of common Horseflies, Morgai Flies are large and dun, gray, or black in color, with red eyes and a red blotch, like Sauron's Lidless Eye, on their backs. Many chroniclers believe them to be monsters of the Dark Lord's design. This may be true of some of the larger subgroups, but those of the basic variety are simply huge, primeval vermin.

Morgai Flies carry virtually all bloodborne diseases, and they played a major part in spreading the Great Plague of T.A. 1636-37.