Section of Brachycera. There are two large families in this group, Syrphidae and Phoridae, and a number of smaller ones. They do not possess a ptilinum, and therefore lack the prominent ptilinal suture on the face as in other muscoid (Muscomorpha) flies.
They do still have a puparium with a circular emergence opening, but it is not as precisely ellipsoid in shape as is typical for other muscoids.
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