[16] The lower part of the section (up to Bed KH-20) does not contain fusulinids. The interbeds of biodetrital limestones enclose mainly fragments of bryozoans, less frequent brachiopods, crinoids, gastropods, and rare small foraminifers, such as Tuberitina, Globivalvulina, Palaeotextularia, Climacammina, Cribrogenerina and some others. Fusulinids represented by abundant badly preserved tests of unidentifiable species of Pseudoendothyra were first discovered in Bed KH-7. Single Pseudofusulina were found in beds KH-10, KH-14, and KH-18 but occur in abundance in beds KH-20-KH-26. They are frequently associated with subordinate Eoparafusulina. Primitive Eoschubertella and representatives of Pseudoendothyridae ( Pseudoendothyra sp. and Palaeostaffella? sp.) are very rare. No trends of distribution of Pseudofusulina and Eoparafusulina throughout the section have been recorded, and the assemblage is perceived as a single whole.
[17] As a whole, the assemblage has a peculiar character due to endemic species of Pseudofusulina, which do not occur in most of the known Permian sections of the Tethyan region. It shows a close similarity only to so called "Kalaktash" assemblage from a Lower Permian section of Central Pamirs [Leven, 1993], which is also dominated by Pseudofusulina and shares some species of Pseudofusulina and Eoparafusulina. The only distinction of the "Kalaktash" assemblage is the presence of Sphaeroschwagerina, Robustoschwagerina and Zellia, which are however rare and were discovered by examining a great number of thin sections (several thousands). The Iranian material is only 115 thin stctions, so chances to detect these forms, even if they initially occurred together with Pseudofusilina, are few. In spite of great morphological varieties of the Pseudofusilina forms, most of them show differently pronounced distinctions of early whorls from later ones. This feature is characteristic of many species of the Kalaktash assemblage.
[18] Endemic fusulinid assemblages composed mostly by
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[19] Pseudofusulina curteum Leven (Plate 1, Images 1-4) having a short fusiform shell with flattened central part, sharply increased spiral coiling after the third whorl, small axial fillings in juvenarium. Iranian representatives of the species are not actually different from typical forms described first from the Kalaktash section of Central Pamirs (see [Leven, 1993, Plate 4, Images 5, 7; Plate 5, Images 1, 3]).
[20] Pseudofusulina karapetovi Leven reported from both the Central Pamirs section and sections of Hindukush, Afghanistan, and Oman. In the Iranian materials it is represented by two subspecies:
[21] Pseudofusulina karapetovi karapetovi Leven (Plate 3, Images 1-4) having true fusiform shell with pointed poles, relatively uniform spiral coiling, and indistinct secondary deposits in initial whorls. The subspecies was first described from South Afghanistan (see [Leven, 1997, Plate 11, Images 1-5]) and occurs in abundance in the Kalaktash assemblage of Central Pamirs (see [Leven, 1993, Plate 1, Images 4, 9]).
[22] Pseudofusulina karapetovi tezakensis Leven (Plate 3, Images 5-8) distinguished from the preceding subspecies by shorter shell and better pronounced secondary deposits in two or three initial whorls. It was also first found from South Afghanistan (see [Leven, 1997, Plate 11, Images 9-11]) and recorded in the Pamirs (see [Leven, 1993, Plate 1, Images 5, 7]) and Oman (see [Angiolini et al., 2006, Plate 1, Images 7-10]).
[23] Pseudofusulina kalaktashensis Leven (Plate 1, Images 5, 6) represented by forms close to typical representatives of the species from Central Pamirs (see [Leven, 1993, Plate 2, Images 4-6]) but distinguished by shoter shell and relatively irregular septal fluting.
[24] Pseudofusulina licis Leven (Plate 3, Image 9) represented by forms whose parameters are identical of those of type specimens from the Kalaktash section (see [Leven, 1993, Plate 6, Images 3, 4]).
[25] Pseudofusulina insignis Leven (Plate 4, Images 4, 6) similar to typical representatives from the Kalaktash section of Central Pamirs (see [Leven, 1993, Plate 4, Images 6, 8]). Similar forms were found in the Rosh Gol section of Eastern Hindukush [Gaetani and Leven, 1993].
[26] Pseudofusulina aff. perrara Leven (Plate 5, Image 5) distinguished from typical representatives of the species from the Kalaktash section by less elongated shell.
[27] Pseudofusulina ex gr. pamirensis Leven (Plate 5, Images 1-4) having big elongated shell and thus similar to the Kalaktash typical representatives of the species but distinguished by less regular septal fluring.
[28] Pseudofusulina aff. gravis Leven (Plate 5, Image 6) resembling forms of this species from Central Pamirs (see [Leven, 1993, Plate 6, Images 6-8, 10]), but differing in looser spiral coiling.
[29] Beside the listed species of Pseudofusulina, which were identified to the species of the Kalaktash assemblage, the assemblage studied includes unidentifiable forms that may represent new species. Two species were named ( Pseudofusulina kalmardensis and P. gachalensis) and described below. The rest forms were only numbered from 1 to 4.
[30] As noted above, important components of this assemblage, as in the Kalaktash assemblage of Central Pamirs, are species of Eoparafusulina. All of them belong to the group of Eoparafusulina tschernyschewi (Schellwien) characteristic of the Tastuba Horizon of the Sakmarian Stage of Timan [Grozdilova and Lebedeva, 1961]. The Iranian collection contains four species of the group, i.e., E. tschernyschewi (Schellwien), E. regina Nie et Song, E. pamirensis Leven, and E. cf. oblonga (Grozdilova et Lebedeva). The former three species were described from the Kalaktash assemblage [Leven, 1993]. E. pamirensis was also found in the Lupgar section of Northern Karakorum [Gaetani et al., 1995]. Forms similar to E. regina were recorded in the Gudri-Mazar section of South Afghanistan, where they are associated with Pseudofusulina karapetovi typical of the Kalaktash assemblage and described as a new species E. afghanensis (Leven). The four of the listed species E. oblonga is characteristic of the lower Sakmarian (Tastuba) deposits of Timan.
[31] The listed species of Pseudofusulina and Eoparafusulina are main components of the assemblage studied. There are also single Eoschubertella cf. obscura (Lee et Chen), Pseudoendothyra sp., and Palaeostaffella? sp. having a wide stratigraphic range but occurring in most abundance in the Middle Carboniferous.
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