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Drymosphaera (?) pseudosagenoscena Sugiyama, 1992

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Drymosphaera (?) pseudosagenoscena

Description: Central sphere single, small, latticed by cylindrical bars generally forming triclade, rarely diclade corners and polygonally shaped pores. The radial spines arising from the corners, generally more than 15 in number, very long, having three or four verticils disposed nearly at the same intervals, proximally cylindrical, distally becoming thick and changing into three-bladed beyond the first verticils. From each verticil arise cylindrical and straight bars, which are thinner than ones forming the central sphere and perpendicular to the radial spine. This type of radiation resulting in forming three or four lattice-plates with large, triangular meshes. Moreover, some bars developed obliquely from a verticil to preceding and following ones on neighboring spines. All bar is not hollow.
Remarks: The generic assignment is quite tentative. This species may belong to a new genus but the proposal is reserved in this time. It differs from other actinommids in its shell structure, particularly the presence of the characteristic lattice-plates described above. The construction of the lattice-plates is similar to that of phaeodarian genus Sagenoscena Haeckel, 1887. The abundance is very rare in the samples TH-1, 2 and 4.
Dimensions (in µm): Based on seven specimens. Diameter of central sphere; 22-40. Length of radial spine; up to 330.
Holotype: ESN 146851 (PL 9, figs, la, lb) from TH-2.
Etymology: From the Greek pseudes, false, and the generic name Sagenoscena Haeckel.
Sugiyama 1992


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