Genus Rugosofusulina Rauser-Chernousova, 1937

Rugosofusulina

(?) iranica Leven, n. sp.
Plate 5, figs. 1, 2

Etymology.
[63]  The species name is derived from the word Iran.
Holotype.
[64]  GIN 4781/70. Axial section; Iran, Anarak, Zaladou Formation, Sample AC14; Carboniferous, Pennsylvanian, late Kasimovian (?)-early Gzhelian.

Material.
[65]  2 axial sections.
Description.
[66]  Shell moderately large, short fusiform in first 3 whorls and elongate fusiform, with bluntly rounded poles in following ones. Mature individuals 4.5 to 5 volutions and measure 6.3 mm to 7.5 mm in length and 2 mm in diameter; form ratio 3.12 to 3.75. Shell loosely coiled except for first 2 to 3 whorls. Waved and here and there corrugated spirotheca composed of tectum and thin alveolar keriotheca 0.07 mm to 0.08 mm thick in last volution. Septa strongly but irregularly fluted throughout shell; septal folds of different height and shape. Proloculus moderately large, its outside diameter 0.17 mm. Tunnel half as high as chamber, narrow in inner 2 to 3 volutions, significantly widening outwards. Clear, narrow and high chomata developed in early 3 volutions.

Discussion.
[67]  The species is referred to Rugosofusulina by convention, for its spirotheca is not as waved and corrugated as described in the diagnosis of the genus. At the same time the wavy spirotheca does not permit the assignment of the species to Triticites, which forms are similar to it in all parameters excluding the character of spirotheca. Rugosofusulina (?) iranica closely resembles R. scaphulaeformis Semikhatova known from the Triticites quasiarcticus-Tr. acutus Zone of the Kasimovian in the Donetsk basin, differing from it in a tighter coiling of inner whorls, their more elongated form, and in slightly more fluted septa.

Occurrence and age.
[68]  The same as holotype.

Rugosofusulina

(?) elongata Leven, n. sp. Plate 5, figs 3-6

Etymology.
[69]  Elongata - elongated.
Holotype.
[70]  GIN 4781/88. Axial section; Iran, Anarak, Zaladou Formation, Sample AC14; Carboniferous, Pennsylvanian, late Kasimovian (?) or early Gzhelian.

Material.
[71]  5 axial sections.
Description.
[72]  Shell fairly large, elongated, subcylindrical, with bluntly rounded to bluntly pointed poles. Mature shell has 4 to 4.5 volutions and measures 5 mm to 7 mm in length and 1.4 mm to 1.7 mm in diameter; form ratio 3.5 to 4.1. Spirotheca waved in first two whorls and more or less corrugated in following ones. Spirotheca composed of tectum and thin alveolar keriotheca; its thickness 0.07 mm in outer volution. Septa strongly and irregularly fluted; septal folds of different height and shape. Proloculus moderately large, its outside diameter 0.17 mm. Tunnel half as high as chamber, narrow in inner two volutions, significantly widening outwards. Clear rounded chomata developed in proloculus and two early volutions.

Discussion.
[73]  Rugosofusulina (?) elongata n. sp. differs from R. (?) iranica n. sp. in its subcylindrical shape of shell and more pronounced corrugation of spirotheca.

Occurrence and age.
[74]  The same as holotype.
RJES

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