Neoplanorbulinella matsumarui, Gedik, 2017

Gedik, Fatma, 2017, First record of the new Neoplanorbulinid species (Foraminifera) from the Early Oligocene in Turkey, Malatya Basin, Eastern Taurids, Geodiversitas 39 (2), pp. 273-284 : 280

Neoplanorbulinella matsumarui n. sp. ( Fig. 6 A-D)

HOLOTYPE. — Axial section, Fig. 6A (sample no. HYM-36A/5/2).

TYPE LOCALITY. — Karamağara village, NE Akçadağ, W Malatya, Eastern Turkey, HYM-first unit.

AGE. — Rupelian-Early Chattian (SB 21-22).

DIAGNOSIS. — Neoplanorbulinella with small, high conical test with almost right apical angle, having equatorial chambers around the cone, and lateral chambers underdeveloped in umbilical cavity, and calcareous wall.

ASSEMBLAGE. — Borelis pygmaea , B. merici , Penarchaias glynnjonesi , Archaias hensoni , Neoplanorbulinella malatyaensis n. sp., Neoplanorbulinella sp., Malatyna sp., Borelis sp., Miogypsinella sp. and Asterigerina sp.

ETYMOLOGY. — This species is dedicated to Professor Kuniteru Matsumaru to acknowledge his contribution to micropaleontological research.

DESCRIPTION

Only megalospheric form is observed. This form has a high conical test with small size. The basal diameter of the cone reaches 0.5 mm, and the maximum cone height is 0.3 mm. The apical angle is about 90°. The large, spherical megalosphere (its diameter 30-92 µm) is situated at the top of the cone, followed by arcuate equatorial chambers. The size of the equatorial chambers increases regularly from apex to the base.

COMPARISON

Neoplanorbulinella matsumarui n. sp. differs from N. saipanensis Matsumaru, 1976 in having high conical test and about 90° apex angle. N. saipanensis has low conical test and about 112° apex angle ( Matsumaru 1976). In addition, the equatorial and

lateral chambers of N. saipanensis are arranged irregularly. The equatorial chambers of the new species are arranged regularly, and the connection of chambers is provided with stolons.