Description of New Specie
Pseudofusulina gachalensis Leven, n. sp.
[44] Plate 2, Images 1-5
Etymology.
[45] The species is named for the Gachal section where it was found.
Holotype.
[46] GIN 4782/9. Subaxial section; Iran, Gachal section, Khan Formation; Lower Permian,
Sakmarian (?).
Material.
[47] 8 axial and subaxial sections.
Description.
[48] Shell moderately large, irregular fusiform to subcylindrical, with bluntly pointed
poles. Adult specimens have 5 to 5.5 volutions and measure 8.5 to 11 mm in length and 2.3 to 2.8 mm
in diameter. First 2 to 3.5 whorls rather tightly coiled but later ones loose; form ratio 3.3 to 4.2.
Spirotheca composed of tectum and rather fine-textured keriotheca 0.1 to 0.12 mm thick in outer
volution. Septa thin strongly fluted from pole to pole rather regularly in inner volutions and very
irregularly in later ones. Proloculus small, its outside diameter 0.175 to 0.185 mm. Tunnel low and
not very wide. Chomata weak, present in first one-two volutions. Small axial fillings sometimes
present in first two or three volutions.
Discussion.
[49] The species is characterized by sharp differences in shell form, spiral coiling and
fluting at early and later stages of evolution: as spiral becomes wider, shell wall is curved and
fluting is irregular. In this respect the species somewhat resembles Pseudofusulina curteum Leven
but differs in very elongated shell.
Stratigraphic range and occurrence.
[50] The same as holotype.
Pseudofusulina kalmardensis Leven, n. sp.
[51] Plate 4, Images 1-3
Etymology.
[52] The species is named for the Kalmard area where Gachal section is locate.
Holotype.
[53] GIN 4782/23. Axial section; Iran, Gachal section, Khan Formation; Lower Permian,
Sakmarian (?).
Material.
[54] 3 axial and 2 sagittal sections.
Description.
[55] Shell moderately large, elongate fusiform with bluntly rounded to bluntly pointed
poles. Adult specimens have 4.5 to 5.5 loosely coiled volutions and measure 9 to 10 mm in length
and 2.7 to 3 mm in diameter; early 1.5 to 2 whorls rather tightly coiled but later ones loose; form
ratio 3.3 to 3.8. Spirotheca composed of tectum and rather fine-textured keriotheca 0.07 to 0.10 mm
thick in outer volution. Septa thin strongly fluted from pole to pole. Septal folds rather high and
rounded. Proloculus middle of size, its outside diameter 0.12 to 0.18 mm. Tunnel low and not very
wide. Chomata weak, present in first one-two volutions.
Discussion.
[56] Pseudofusulina kalmardensis n. sp. is distinguished from
P. gachalensis n. sp. by regular shell form, more uniform spiral coiling, and more regular septal fluting.
The species resembles P. moelleri (Schellwien), especially a form from the Tastuba Horizon of Northern Timan
which was arbitrarily referred to this species
[Grozdilova and Lebedeva, 1961, Plate 12, Image 4].
From true P. moelleri it differs in looser coiling and looser and less regular septal fluting.
Stratigraphic range and occurrence.
[57] The same as holotype.
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