Genus Rauserites Rozovskaya, 1950
Genus
Rauserites Rozovskaya,
1950
Rauserites stepanovi
Leven, n. sp.
Plate 4, figs 5, 7, 8
Etymology.
[51] The species named in honor of Professor D. L. Stepanov,
the outstanding investigator of the Carboniferous and Permian of Iran.
Holotype.
[52] GIN 4781/62. Subaxial section; Iran, Anarak, Zaladou Formation,
Sample C23; Carboniferous, Pennsylvanian, Gzhelian.
Material.
[53] 5 axial and subaxial sections.
Description.
[54] Shell small, fusiform, with bluntly rounded poles. Mature shell
has 5 to 5.5 volutions and measures 4.9 mm to 6.3 mm in length and 1.7 mm to 2.2 mm in diameter;
form ratio 2.7 to 2.9. First 3 to 3.5 whorls rather tightly coiled, after which coiling becomes
loose. Spirotheca composed of tectum and moderately coarse keriotheca, 0.07 mm to 0.08 mm thick
in last whorl. Septa rather strongly and very irregularly fluted from pole to pole.
Septal folds high and wide. Proloculus moderately sized, its outside diameter 0.125 mm.
Tunnel low and wide. Chomata weak, present only on proloculus and in 2 or 3 inner
whorls. Axial filling is absent.
Discussion.
[55] Rauserites stepanovi n. sp. is the most similar to
"Triticites" tabinicus Alksne from the boundary Kasimovian and Gzhelian sediments of the Urals,
but differs in a more elongated shell, particularly in the inner whorls, and in a more uniform coiling.
Occurrence and age.
[56] The same as holotype.
Rauserites
(?)
persicus Leven, n. sp. Plate 3, figs 7-9
Etymology.
[57] The species name derived from the ancient name of Iran - Persia.
Holotype.
[58] GIN 4781/52. Axial section; Iran, Anarak, Zaladou Formation, Sample
AC14; Carboniferous, Pennsylvanian, late Kasimovian (?) or early Gzhelian.
Material.
[59] 3 axial sections.
Description.
[60] Shell small, fusiform, with straight to slightly convex lateral slopes
and bluntly pointed poles. Adult individuals have 4.5 to 5 volutions and measure 4.5 mm to 5.3 mm
in length and 1.5 mm to 1.9 mm in diameter; form ratio 2.7 to 3.3. Irregular undulated
spirotheca composed of tectum and fine textured keriotheca; thickness in last whorl 0.6 mm to
0.8 mm. First 1 or 2 whorls rather tightly coiled but later ones looser. Septa rather
strongly fluted from pole to pole. Septal folds irregular, high, usually reaching tops of
septa. Proloculus small, its outside diameter 0.05. Tunnel narrow and poorly observed.
Chomata weak, present only on proloculus and in first one or two whorls.
Discussion.
[61] The species differs from all the Rauserites members in a small
proloculus; irregular coiling, tight in the initial whorls and looser in the last whorl; and in
weakly developed chomata. The attribution of our species to Rauserites is not obvious,
however, it cannot be referred with enough reason to any other known genus.
Occurrence and age.
[62] Iran, Anarak, Zaladou Formation, Samples AC14 and RL;
Pennsylvanian, late Kasimovian(?)-early Gzhelian.
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