Dalongicaepa bipolaris Xiao and Suzuki, 2017

Xiao, Yifan, Suzuki, Noritoshi & He, Weihong, 2017, Applications and limitations of micro-XCT imaging in the studies of Permian radiolarians: A new genus with bi-polar main spines, Acta Palaeontologica Polonica 62 (3), pp. 647-656 : 650

Dalongicaepa bipolaris Xiao and Suzuki sp. nov.

Fig. 1.

Etymology: From Latin bi- and polaris, two polars; in reference to the bipolar arrangement of the two polar spines.

Type material: Holotype ( LGFEC SR 69-057 ), Fig. 1H . Paratype ( LGFEC SR 69-028 ), Fig. 1A .

Type locality: Hunan Province, South China .

Type horizon: Upper Dalong Formation ; upper Changhsingian .

Material. — Nine specimens (LGFEC SR 69-028, 69-029, 69-035, 69-057, 69-058, 69-062, 69-069, 69-090, 69-091).

Diagnosis. —Spongy spherical shell of two long bi-polar spines with uneven length.

Description. —Test spherical and spongy, composed of four to seven concentric shells. Two rod-like spines are thin, gradually decreasing in width distally, but quite different in length and arrangement: shorter or longer, straight or curving, opposite or obliquely opposed. In some specimens, the spines are particularly long and the length of spines can be twice longer than the diameter of the shell.

Measurements (in μm).—Diameter of test 159–179, length of spines 209–300, width of spines near base 14–29 (based on nine specimens).

Remarks. —The superficial appearance of this new species may be confused with two late Permian species Dalongicaepa fontainei and Archaeospongoprunum mengi . D. bipolaris Xiao and Suzuki gen. et sp. nov. is different from D. fontainei by having more concentric shells, spherical cortical shell, and longer thin polar main spines. Besides, the polar main spines of the new species distally decrease in width and sometimes curve. The new species is easily distinguished from A. mengi in the outline of its shell outline and three-bladed polar main spines.

Stratigraphic and geographic range. — Type locality and horizon only.