Species name: Muscina stabulans (Fallén)
Family: Muscidae

The false stable fly is not a bloodsucker and has sponging-sucking mouthparts like the house fly. It is larger and more robust than the house fly. Overall color is dark gray, with the head a lighter whitish-gray.

The gray thorax has four longitudinal stripes and the posterior tip of the scutellum (dorsal rear lobe of the thorax) is pale yellow. The abdomen is gray and black with a blotched appearance.

The fourth longitudinal vein (M1+2) of the wings is not bent and converges only slightly towards the vein in front of it; this is similar to the arrangement in the stable fly and quite different from the sharply bent vein in the house fly (Figure 16D).

The legs of the false stable fly are partly red-gold or cinnamon. A closely-related species, Muscina assimilis (Fallén) [= Muscina levida (Harris)], may be encountered in and around animal production facilities, but its legs are entirely black.

The false stable fly is sometimes fairly abundant in animal facilities, especially in poultry houses where it breeds in accumulated manure. Overall, it is seldom as abundant as other filth flies, however.

The larvae of Muscina stabulans will prey on other fly larvae, including those of the house fly. However, this predation is limited, and although the few experimental results are conflicting, it appears not to be a significant factor in controlling house flies or other pest species of flies breeding in animal facilities.