The family Sepsidae is composed of more than 350 declared species in the world. This family belongs to superfamily Sciomyzoidea incuding of 2 subfamilies Sepsinae Walker, 1833 and Orygmatinae Frey, 1921 which the recent subfamily has only one genus Orygma Meigen, 1830. The largest genus of this family is Sepsis Fallén, 1810 which belongs to subfamily Sepsinae. The external morphological characteristics of the family Sepsidae are as follows: relatively small size (2-12 mm), shiny, slender and ant like body, head rounded, wings clear, sometimes with round spot near apex of vein R2+3, no costal breaks, postvertical setae divergent or absent in some species, the palpi are minute except in genus Orygma, Legs are rather long, slender and fore legs of males except of the genus Orygma, having stout setulae, spines, pegs, tubercles and protuberances. Some species exhibit considerable variation, which case more synonymy in this family. It has been reported 12 species of this family from Iran so far. In order to identification of the family, materials were collected by a standard entomological handy net from grasslands and forests situated in East Azerbaijan, West Azerbaijan, Lorestan and Kordestan provinces, during 2011- 2017. A total eight species belonging to two genera of the subfamily Sepsinae were identified which among them, three species marked with an asterisk (*) are recorded for the first time from Iran.
*Saltella nigripes Robineau-Desvoidy, 1830
Sepsis biflexuosa Strobl, 1893
*Sepsis cynipsea (Linnaeus, 1758)
Sepsis fulgens Meigen, 1826
*Sepsis lateralis Wiedemann, 1830
Sepsis punctum (Fabricius, 1794)
Sepsis thoracica (Robineau-Desvoidy, 1830)
Sepsis violacea Meigen, 1826