Eudiptera is a suborder of Diptera

Diptera

Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...

 under an alternative subordinal classification based largely on fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 taxa; it has not gained wide acceptance among non-paleontological dipterists and is presented here for comparative purposes only.

All of the taxa included in Eudiptera are also members of the Nematocera

Nematocera

Nematocera , is a suborder of elongated flies with thin, segmented antennae and mostly aquatic larvae, consisting of the mosquitoes, crane flies, gnats, and midges....

, and the latter is the preferred grouping; both are paraphyletic.