NOMEN: Mesodiptera Crampton 1916: 302 [G.C. Crampton. The lines of descent of the lower pterygotan insects, with notes on the relationships of the other forms. – Entomological News, 1916, 27 (7): 297-307]
ORIGINAL LISTED MEMBERSHIP (Crampton 1916):
"Leptid group" 
SENIOR CIRCUMSCRIPTIONAL SYNONYM:
= "Brachycera-Orthorrhapha" auct. (non Brachycera; nec Orthorrhapha)
TYPIFIED NAME IN BASIC FORMAT: Bombylius/f=Tabanus/g
TYPIFIED NAMES IN USE:
MODERN
STATUS: 
the valid, the
oldest name of a generally accepted plesiomorphon.
Systematic position of
Mesodiptera:
| Diptera plesiomorphon Nemocera Brachocera plesiomorphon Mesodiptera Cyclorapha |