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Batiacasphaera solida
Batiacasphaera solida, Slimani, 2003, p.268-269,271,273, pl.1, figs.1-7.
Taxonomic junior synonym: Chytroeisphaeridia solida (name not validly published) according to Slimani (2003, p.268-269).
Holotype: Slimani, 2003, pl.1, fig.1.
Type locality: Turnhout (northern Belgium), borehole 17 E225 (S120) of the Geological Survey of Belgium.
Type stratum: Upper Campanian, White chalk, Zeven Wegen Member, Turnhout 933 m (below ground surface).
Age: Campanian.
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Original description: [Slimani, 2003]:
Diagnosis:
A species of Batiacasphaera with a sub-spherical, ovoidal to pear-shaped autocyst with a thick, coarsely granulate to tuberculate wall.
Apical archeopyle (type tA) with an angular margin and a free operculum.
Description:
Acavate, proximate, sub-spherical to pear-shaped dinoflagellate cyst.
The cyst wall consists of a massive and thick (up to 4 µm) autophragm. The autophragm is finely reticulate and has granules or tubercles (up to 2.5 µm in diameter) with a more or less regular distribution.
The archeopyle is sub-hexagonal and angular with a parasulcal notch.
There are fine accessory parasutures between the precingular paraplates.
Dimensions:
Holotype: length, 62 µm; width, 58 µm;
Paratype 1: length, 56 µm; width, 46 µm; paratype 2, length, 54 µm; width, 50 µm.
Range of 10 measured specimens: length, 54 (59) 64 µm; width, 44 (51) 58 µm.
Affinities/Discussion:
Batiacasphaera solida Slimani, sp. nov. is closely comparable to specimens of ‘Chytroeisphaeridia solida’, described informally by Wilson (1974). The new species is herein attributed to the genus Batiacasphaera Drugg, 1970 as it has an apical rather than precingular archeopyle. Batiacasphaera euteiches (Davey, 1969a) Davey, 1979 also has a thick wall, but it is finely granulate; Batiacasphaera reticulata (Davey, 1969b) Davey, 1979 has a finely reticulate wall and is smaller than the new species. Pyxidiella? scrobiculata (Deflandre and Cookson, 1955) Cookson and Eisenack, 1958 is similar in its ornamentation but differs in having a smaller and uncertain but probably intercalary, archeopyle. Palaeostomocystis ovata (Wilson, 1967) Eisenack et al., 1973 differs from the new species in having a finely granulate but thin wall and a round archeopyle. Specimens of Batiacasphaera (?) reticulata recorded from the Upper Cretaceous of Maud Rise and the Georgia Basin (Antarctic) by Mohr and Mao (1997, pl. 1, ¢g. 5) are closey similar to B. solida. Batiacasphaera baculata Drugg, 1970 and Batiacasphaera compta Drugg, 1970 differs from the new species in having different cyst wall ornamentations, with baculate and rodshaped elements respectively. Cyst walls of Batiacasphaera granulosa (Cookson and Eisenack, 1974) Jansonius, 1989 and Batiacasphaera subtilis Stover and Helby, 1987 are not reticulate as that of the new species.
Taxonomic junior synonym: Chytroeisphaeridia solida (name not validly published) according to Slimani (2003, p.268-269).
Holotype: Slimani, 2003, pl.1, fig.1.
Type locality: Turnhout (northern Belgium), borehole 17 E225 (S120) of the Geological Survey of Belgium.
Type stratum: Upper Campanian, White chalk, Zeven Wegen Member, Turnhout 933 m (below ground surface).
Age: Campanian.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Slimani, 2003]:
Diagnosis:
A species of Batiacasphaera with a sub-spherical, ovoidal to pear-shaped autocyst with a thick, coarsely granulate to tuberculate wall.
Apical archeopyle (type tA) with an angular margin and a free operculum.
Description:
Acavate, proximate, sub-spherical to pear-shaped dinoflagellate cyst.
The cyst wall consists of a massive and thick (up to 4 µm) autophragm. The autophragm is finely reticulate and has granules or tubercles (up to 2.5 µm in diameter) with a more or less regular distribution.
The archeopyle is sub-hexagonal and angular with a parasulcal notch.
There are fine accessory parasutures between the precingular paraplates.
Dimensions:
Holotype: length, 62 µm; width, 58 µm;
Paratype 1: length, 56 µm; width, 46 µm; paratype 2, length, 54 µm; width, 50 µm.
Range of 10 measured specimens: length, 54 (59) 64 µm; width, 44 (51) 58 µm.
Affinities/Discussion:
Batiacasphaera solida Slimani, sp. nov. is closely comparable to specimens of ‘Chytroeisphaeridia solida’, described informally by Wilson (1974). The new species is herein attributed to the genus Batiacasphaera Drugg, 1970 as it has an apical rather than precingular archeopyle. Batiacasphaera euteiches (Davey, 1969a) Davey, 1979 also has a thick wall, but it is finely granulate; Batiacasphaera reticulata (Davey, 1969b) Davey, 1979 has a finely reticulate wall and is smaller than the new species. Pyxidiella? scrobiculata (Deflandre and Cookson, 1955) Cookson and Eisenack, 1958 is similar in its ornamentation but differs in having a smaller and uncertain but probably intercalary, archeopyle. Palaeostomocystis ovata (Wilson, 1967) Eisenack et al., 1973 differs from the new species in having a finely granulate but thin wall and a round archeopyle. Specimens of Batiacasphaera (?) reticulata recorded from the Upper Cretaceous of Maud Rise and the Georgia Basin (Antarctic) by Mohr and Mao (1997, pl. 1, ¢g. 5) are closey similar to B. solida. Batiacasphaera baculata Drugg, 1970 and Batiacasphaera compta Drugg, 1970 differs from the new species in having different cyst wall ornamentations, with baculate and rodshaped elements respectively. Cyst walls of Batiacasphaera granulosa (Cookson and Eisenack, 1974) Jansonius, 1989 and Batiacasphaera subtilis Stover and Helby, 1987 are not reticulate as that of the new species.