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Tetrachacysta baculata
From Fensome et al., 2019:
Tetrachacysta? baculata Backhouse, 1988, p.110–111, pl.42, figs.4–5; pl.51, figs.2–3.
Holotype: Backhouse, 1988, pl.42, fig.5; Fensome et al., 1996, fig.2 — p.2059.
Questionable assignment: Backhouse (1988, p.110).
Age: late Tithonian–Valanginian.
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Original description: [Backhouse, 1988]:
Tetrachacysta? baculata sp. nov.
P1. 42, figs 4, 5; P1. 5 1, figs 2, 3
Derivation of name: Latin, baculus, a rod, alluding to the surface elements.
Holotype: F8354/1 (~42.1, -96.6) Eneabba Line 3B, 490 m, Parmelia F;ormation, P1. 42, fig. 5.
Description: Cysts small, strongly quadrilobate, slightly dorso-ventrally flattened, epicyst and hypocyst similar in width. Aulophragm 0.5 to
1.0 μm thick: bcaring bacula, verrucac, or rarely clavae to 1 μm high. Surface clements subdued in cingular area and in slight apical and antapical indentations. Paratabulation expressed only at archeopyle suture, but precise number of precingular paraplates not determined on any specimen observed. Archcopyle apical, type [tA]. operculum flat and often in position. Archeopyle usually difficult to detcct.
Dimensions: Length of holotype 55, width 55 μm. Range of length (17 Specimens) 30(42)56 μm, width 30(40)55 μm.
Remarks: Tetrachacysta? baculata is more strongly lobate, more angular inoutline, possesses a less prominent archeopyle and bears coarser surface elements than T allenii. It differs from T . spinosigibberosa by being approximately equidimensional, bearing predominantly baculate
surface features, and lacking paratabulation. Until more is known about the archeopyle, this species is only provisionally assigned to Tetrachacysta.
Range: Fusiformacysta tumida and Gagiella mutabilis Zones. The distribution of Tetrachacysta baculata suggests a freshwater, or brackish water, or restricted marine origin for the species.
Tetrachacysta? baculata Backhouse, 1988, p.110–111, pl.42, figs.4–5; pl.51, figs.2–3.
Holotype: Backhouse, 1988, pl.42, fig.5; Fensome et al., 1996, fig.2 — p.2059.
Questionable assignment: Backhouse (1988, p.110).
Age: late Tithonian–Valanginian.
---------------------------------------------------------------------------------------------------
Original description: [Backhouse, 1988]:
Tetrachacysta? baculata sp. nov.
P1. 42, figs 4, 5; P1. 5 1, figs 2, 3
Derivation of name: Latin, baculus, a rod, alluding to the surface elements.
Holotype: F8354/1 (~42.1, -96.6) Eneabba Line 3B, 490 m, Parmelia F;ormation, P1. 42, fig. 5.
Description: Cysts small, strongly quadrilobate, slightly dorso-ventrally flattened, epicyst and hypocyst similar in width. Aulophragm 0.5 to
1.0 μm thick: bcaring bacula, verrucac, or rarely clavae to 1 μm high. Surface clements subdued in cingular area and in slight apical and antapical indentations. Paratabulation expressed only at archeopyle suture, but precise number of precingular paraplates not determined on any specimen observed. Archcopyle apical, type [tA]. operculum flat and often in position. Archeopyle usually difficult to detcct.
Dimensions: Length of holotype 55, width 55 μm. Range of length (17 Specimens) 30(42)56 μm, width 30(40)55 μm.
Remarks: Tetrachacysta? baculata is more strongly lobate, more angular inoutline, possesses a less prominent archeopyle and bears coarser surface elements than T allenii. It differs from T . spinosigibberosa by being approximately equidimensional, bearing predominantly baculate
surface features, and lacking paratabulation. Until more is known about the archeopyle, this species is only provisionally assigned to Tetrachacysta.
Range: Fusiformacysta tumida and Gagiella mutabilis Zones. The distribution of Tetrachacysta baculata suggests a freshwater, or brackish water, or restricted marine origin for the species.