Orthorrhapha is a circumscriptional name

Circumscriptional name

Circumscriptional names are taxon names used above family-group level that are not ruled by ICZN and are defined by the particular set of members included, not the number of species....

 which historically was used for an infraorder of Brachycera

Brachycera

Brachycera is a suborder of Diptera. It is a major suborder consisting of around 120 families. The most distinguishing characteristic of the suborder is reduced antenna segmentation...

, one of the two suborders into which the order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 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...

, the flies, are divided. As the group was paraphyletic, it has not been used in classifications in the last decade, and is effectively obsolete. However, many catalogs, checklists, and older works still contain the name. The taxa that used to be in the Orthorrhapha now comprise all of the infraorders in Brachycera excluding the Muscomorpha

Muscomorpha

The Brachyceran infraorder Muscomorpha is a large and diverse group of flies, containing the bulk of the Brachycera, and, in fact, most of the known flies. It includes a number of the most familiar flies, such as the housefly, the fruit fly and the blowfly. The antennae are short, usually...

(= "Cyclorrhapha").