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Heterosphaeridium
From Fensome et al., 2019:
Heterosphaeridium, Cookson and Eisenack, 1968, p.115.
Emendation: Yun Hyesu, 1981, p.45–46.
Type: Cookson and Eisenack, 1968, text-fig.4H, as Heterosphaeridium conjunctum.
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Original description: [Cookson and Eisenack, 1968]:
Description:
Shell circular in outline with numerous solid appendages of varying widths in one and the same specimen and opening by the removal of the whole apex along a straight line.
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Stover and Evitt, 1978, p. 115:
Remark:
Contrary to the statement in the original description, principal archeopyle suture appears to be slightly zigzag (not straight) and indicates a Type tA archeopyle. The position of the sulcal notch is not determinable from the illustrations; hence, whether the body is subspherical or lenticular cannot be ascertained. Because Cookson & Eisenack (1968, p. 115) state that the bases of the processes "are frequently joined by relatively broad surface ridges which delimit relatively large polygonal areas,`` we suspect that Heterosphaeridium conjunctum is probably a species of Systematophora, but we hesitate to make the transfer until more is known about the species.
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Emended description:
Yun, 1981:
Diagnosis:
Chorate proximochorate cyst with numerous, differently formed, simple or branched spines. Of these, a view can be connected proximally and/or distally. On one specimen solid or solid and hollow spines can be developed. Archeopyle apical.
Heterosphaeridium, Cookson and Eisenack, 1968, p.115.
Emendation: Yun Hyesu, 1981, p.45–46.
Type: Cookson and Eisenack, 1968, text-fig.4H, as Heterosphaeridium conjunctum.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1968]:
Description:
Shell circular in outline with numerous solid appendages of varying widths in one and the same specimen and opening by the removal of the whole apex along a straight line.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Stover and Evitt, 1978, p. 115:
Remark:
Contrary to the statement in the original description, principal archeopyle suture appears to be slightly zigzag (not straight) and indicates a Type tA archeopyle. The position of the sulcal notch is not determinable from the illustrations; hence, whether the body is subspherical or lenticular cannot be ascertained. Because Cookson & Eisenack (1968, p. 115) state that the bases of the processes "are frequently joined by relatively broad surface ridges which delimit relatively large polygonal areas,`` we suspect that Heterosphaeridium conjunctum is probably a species of Systematophora, but we hesitate to make the transfer until more is known about the species.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Yun, 1981:
Diagnosis:
Chorate proximochorate cyst with numerous, differently formed, simple or branched spines. Of these, a view can be connected proximally and/or distally. On one specimen solid or solid and hollow spines can be developed. Archeopyle apical.