Abstract
Neosilphitrombium tenebrionidum sp. nov. (Acari: Neothrombiidae) is described and illustrated from larvae ectoparasitic on Opatroides punctatus BruUe, 1832 (Coleoptera: Tenebrionidae) from Mashhad and Gonabad, Razavi JGiorasan Province, Iran. It is the first report of the representatives of the genus Neosilphitrombium from Iran and the first record of the family Tenebrionidae as a host for the genus Neosilphitrombium. A key to world larval species of Neosilphitrombium is presented.