Exceptionally rich Permian fusulinid assemblages, varying in age from Yakhtashian to Dzhulfian, were found in reworked limestone blocks from conglomerates of the Aseelah Unit, recently defined in the Batain Plain and dated possibly as Upper Triassic. This paper only deals with the Middle Permian, Midian (= Capitanian) microfaunas from the conglomerates.
The Aseelah Unit is found associated with the Triassic Sal Formation, tectonically overlying the Qarari Unit, and is dated as Middle to Late Permian based on ammonoid assemblages and conodonts. The boulders of the Aseelah Unit are composed of exclusively Permian skeletal limestones in a sandy matrix; the limestones were deposited on a shallow marine shelf environment from the southern Neotethys. The Qarari Unit is interpreted as a hemipelagic series deposited on the distal slope of the Arabian carbonate platform.
The Midian foraminifers from the Batain Plain are similar to some assemblages of Transcaucasia, of the Abadeh area (Iran), of SW Turkey (Taurus Mountains), and some, especially the Neoschwagerinidae, exhibit affinities with microfaunas of the eastern Tethys terranes of Japan. However, similar Neoschwagerinid assemblages were not found in any significant area of the Arabian Peninsula (Oman Mountains, Huqf-Haushi area, and Khuff area).