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Litosphaeridium oblongum
Litosphaeridium ?oblongum Yu Jingxian and Zhang Wangping, 1980, p.112, pl.4, figs.7-8.
Holotype: Yu Jingxian and Zhang Wangping, 1980, pl.4, fig.8.
Questionable assignment: Lucas-Clark (1984, p.184).
Age: Turonian-Santonian
Original Description Yu Jingxian and Zhang Wangping, 1980 [translation Suning Hou 2025]:
Litosphaeridium oblongum sp. nov.
Holotype: Slide number W3-9D, Plate IV, Figure 8 .
Description: The central body (excluding processes) measures 48.6-50.6 µm in length, with the holotype being 50.6 µm, and 30-36.8 µm in width, with the holotype width being 36.8 µm. The central body is elliptical with a thin wall, and its surface is smooth to slightly granulated. The processes are broad, with each corresponding to a thecal plate. The processes are rectangular, expanded at the tips, and display a saw-tooth-like edge.
Processes associated with the cingulum are small, narrow, measuring approximately 18.4 µm. Postcingular processes: 1’’’ is smaller; 2’’’is longer, ~25.3 µm in length, a basal width of 11.5 µm and has a slightly swollen tip; 3’’’ is the broadest; 5’’’ is smaller; 1’’’’ is short and broad, almost square-shaped. Precingular processes are smaller and shorter comparing to postcingular ones. Apical horn is short. The process walls are thin and bear numerous circular to oval, bead-like protrusions. The archeopyle is apical.
Comparison: The new species is characterized by its nearly rectangular processes with strongly expanded tips and bead-like ornamentation. Its archeopyle characteristics are similar to those of Hystrichosphaeridium cylindratum as described by Brideaux in 1971. However, Morgenroth had already reported Hystrichosphaeridium cylindratum in 1966. Brideaux's species is therefore a homonym and should be abandoned according to the principle of priority.
Stratigraphy: Upper part of the Uytak-Kukbay Formation. 乌依塔克–库克拜上部
Holotype: Yu Jingxian and Zhang Wangping, 1980, pl.4, fig.8.
Questionable assignment: Lucas-Clark (1984, p.184).
Age: Turonian-Santonian
Original Description Yu Jingxian and Zhang Wangping, 1980 [translation Suning Hou 2025]:
Litosphaeridium oblongum sp. nov.
Holotype: Slide number W3-9D, Plate IV, Figure 8 .
Description: The central body (excluding processes) measures 48.6-50.6 µm in length, with the holotype being 50.6 µm, and 30-36.8 µm in width, with the holotype width being 36.8 µm. The central body is elliptical with a thin wall, and its surface is smooth to slightly granulated. The processes are broad, with each corresponding to a thecal plate. The processes are rectangular, expanded at the tips, and display a saw-tooth-like edge.
Processes associated with the cingulum are small, narrow, measuring approximately 18.4 µm. Postcingular processes: 1’’’ is smaller; 2’’’is longer, ~25.3 µm in length, a basal width of 11.5 µm and has a slightly swollen tip; 3’’’ is the broadest; 5’’’ is smaller; 1’’’’ is short and broad, almost square-shaped. Precingular processes are smaller and shorter comparing to postcingular ones. Apical horn is short. The process walls are thin and bear numerous circular to oval, bead-like protrusions. The archeopyle is apical.
Comparison: The new species is characterized by its nearly rectangular processes with strongly expanded tips and bead-like ornamentation. Its archeopyle characteristics are similar to those of Hystrichosphaeridium cylindratum as described by Brideaux in 1971. However, Morgenroth had already reported Hystrichosphaeridium cylindratum in 1966. Brideaux's species is therefore a homonym and should be abandoned according to the principle of priority.
Stratigraphy: Upper part of the Uytak-Kukbay Formation. 乌依塔克–库克拜上部