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Batiacasphaera
From Fensome et al., 2019:
Batiacasphaera, Drugg, 1970b, p.813.
Emendations: Morgan, 1975, p.161; Dörhöfer and Davies, 1980, p.40; Wood et al., 2016, p.62.
Taxonomic junior synonyms: Sentusidinium, according to Dörhöfer and Davies (1980, p.40) -- however, Lentin and Williams (1981, p.253) retained Sentusidinium; Pseudobohaidina, according to He Chengquan et al. (2009, p.326) -- however, Pseudobohaidina is now considered a taxonomic junior synonym of Sentusidinium.
Type: Drugg, 1970b, figs.6A–B, as Batiacasphaera compta.
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Original description: [Drugg, 1970]:
Description:
Tract spherical to subspherical with an angular apical archeopyle. The ornamentation consists of rod-shaped elements, either separated or arranged to form a reticulum. In the latter case they may be fused.
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Emended descriptions:
Morgan, 1975:
Description:
Cyst subspherical to lenticular, with an angular apical archaeopyle Type A. Ornament consists of positive elements which may be separate, or fuse to form rugulae or reticulum. Membranous ornament and tabulation are absent.
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Modified descriptions:
Stover and Evitt, 1978, p. 21:
Synopsis:
Cyst subspherical and without septa, spines or processes; autophragm variously ornamented with isolate and/or fused features that are typically evenly distributed and generally fine; archeopyle apical, Type "tA".
Description:
Shape: Subsperical.
Wall relationships: Autophragm only.
Wall features: Generally no parasutural features; surface features of low relief may be isolated, partly fused or completely fused (reticulate); generally evenly distributed and fine.
Paratabulation: Generally indicated by archeopyle only; occasionally accessory sutures indicate boundaries between precingular paraplates. Paratabulation rarely expressed by surface features.
Archeopyle: Apical, Type "tA"; principal archeopyle suture normally zigzag ; operculum free, constituent paraplates typically undifferentiated.
Paracingulum: Generally not expressed ; rarely indicated by faint alignment of surface features.
Parasulcus: Not expressed.
Size: Small to intermediate.
Affinities:
Batiacasphaera differs from Chytroeisphaeridia in having isolated or fused ornamentation features of low relief, and from Kallosphaeridium in having a free rather than an attached operculum. Retention of Batiacasphaera and Chytroeisphaeridia may be unrealistic unless smooth forms only are assigned to the latter and ornamented forms to the former.
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Dörhöfer and Davies, 1980:
emended the genus to include the remaining species of Tenua after the Holotype of Tenua was transferred to Cyclonephelium and to include those species which where removed from Canningia because they lack indented antacices and asymmetrical archaeopyle sutures.
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Wood et al., 2016:
Genus Batiacasphaera Drugg, 1970 emend. nov.
Type: Batiacasphaera compta Drugg, 1970.
1970 Batiacasphaera Drugg, p. 813.
1975 Batiacasphaera Drugg, 1970 emend. Morgan, p. 161.
1980 Batiacasphaera Drugg, 1970 emend.Dörhöfer and Davies, p. 40.
Original diagnosis: Tract spherical to subspherical with an angular apical archaeopyle. The ornamentation consists of rod–shaped elements, either separate or arranged to form a reticulum. In the latter case, they may be fused (Drugg, 1970, p. 813).
Emended diagnosis: Proximate, acavate gonyaulacalean dinoflagellate cysts with a subspheroidal to ovoidal central body in dorso-ventral view. The autophragm bears nontabulate ornament that is rugulate to reticulate, or isolated elements that align. The archaeopyle is apical, with a free operculum.
Emended description: Small to intermediate, acavate, proximate dinoflagellate cysts that are subspherical to ovoidal in shape, occasionally elongate. The autophragm is generally thick and bears a rugulate to reticulate ornament, or bears typically rod-shaped elements that are arranged, or may fuse, to forma reticulumor polygonal, semi-polygonal or rugulate pattern. The presumed gonyaulacacean tabulation is only indicated by the apical archaeopyle, which normally has a free operculum. Typically, accessory archaeopyle sutures are not, or only weakly, developed, but may be better developed in some species. The cingulum and sulcus are not indicated.
Comments: Morgan (1975, p. 161) gave an emended description for Batiacasphaera in which he noted the lenticular shape and that the ornamentational elements may fuse to form rugulae. We consider the shape to be more subspheroidal than lenticular, but do accept forms in Batiacasphaera with linear ornament consisting of fused elements. Dörhöfer and Davies (1980, p. 40) indicated that they were emending Batiacasphaera but provided neither an emended diagnosis or description nor a clear statement of their generic concept.
We restrict Batiacasphaera to species within the Sentusidinium complex that have a generally reticulate to rugulate ornamentation. Drugg (1970) originally diagnosed Batiacasphaera as having an “angular apical archaeopyle”, implying that the accessory archaeopyle sutures between precingular plates are absent or weakly developed. We found that across the Sentusidinium complexes, using this feature as a defining one at generic level was very difficult to apply. So we re-assign species similar to the type in terms of accessory archaeopyle suture development, such as Batiacasphaera baculata, but with isolated, non-aligned sculptural elements, to Sentusidinium. The lack ofwell-developed accessory archaeopyle sutures can give the superficial impression of a precingular archaeopyle, especially in poorly preserved or obliquely oriented specimens; however, closer examination of better specimens reveals the shape of an apical archaeopyle. The holotype of Batiacasphaera compta, the type of Batiacasphaera, shows an unconventional outline to its archaeopyle and is thus difficult to interpret precisely in terms of tabulation. However, other specimens of Batiacasphaera compta, and other species of the genus show a conventional type (tA) archaeopyle. Fensome and Williams (2004, p. 73–78) listed 49 species of Batiacasphaera. However, only 17 of these species have a rugulate to reticulate
autophragm, and these are all Early Cretaceous to Late Miocene in age. They are listed below in the accepted species list and summarised in Table 1.
Comparison: Batiacasphaera differs from all three other genera in the Sentusidinium complex by its strongly developed reticulate to regulate ornamentation.
Batiacasphaera, Drugg, 1970b, p.813.
Emendations: Morgan, 1975, p.161; Dörhöfer and Davies, 1980, p.40; Wood et al., 2016, p.62.
Taxonomic junior synonyms: Sentusidinium, according to Dörhöfer and Davies (1980, p.40) -- however, Lentin and Williams (1981, p.253) retained Sentusidinium; Pseudobohaidina, according to He Chengquan et al. (2009, p.326) -- however, Pseudobohaidina is now considered a taxonomic junior synonym of Sentusidinium.
Type: Drugg, 1970b, figs.6A–B, as Batiacasphaera compta.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Drugg, 1970]:
Description:
Tract spherical to subspherical with an angular apical archeopyle. The ornamentation consists of rod-shaped elements, either separated or arranged to form a reticulum. In the latter case they may be fused.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended descriptions:
Morgan, 1975:
Description:
Cyst subspherical to lenticular, with an angular apical archaeopyle Type A. Ornament consists of positive elements which may be separate, or fuse to form rugulae or reticulum. Membranous ornament and tabulation are absent.
---------------------------------------
Modified descriptions:
Stover and Evitt, 1978, p. 21:
Synopsis:
Cyst subspherical and without septa, spines or processes; autophragm variously ornamented with isolate and/or fused features that are typically evenly distributed and generally fine; archeopyle apical, Type "tA".
Description:
Shape: Subsperical.
Wall relationships: Autophragm only.
Wall features: Generally no parasutural features; surface features of low relief may be isolated, partly fused or completely fused (reticulate); generally evenly distributed and fine.
Paratabulation: Generally indicated by archeopyle only; occasionally accessory sutures indicate boundaries between precingular paraplates. Paratabulation rarely expressed by surface features.
Archeopyle: Apical, Type "tA"; principal archeopyle suture normally zigzag ; operculum free, constituent paraplates typically undifferentiated.
Paracingulum: Generally not expressed ; rarely indicated by faint alignment of surface features.
Parasulcus: Not expressed.
Size: Small to intermediate.
Affinities:
Batiacasphaera differs from Chytroeisphaeridia in having isolated or fused ornamentation features of low relief, and from Kallosphaeridium in having a free rather than an attached operculum. Retention of Batiacasphaera and Chytroeisphaeridia may be unrealistic unless smooth forms only are assigned to the latter and ornamented forms to the former.
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Dörhöfer and Davies, 1980:
emended the genus to include the remaining species of Tenua after the Holotype of Tenua was transferred to Cyclonephelium and to include those species which where removed from Canningia because they lack indented antacices and asymmetrical archaeopyle sutures.
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Wood et al., 2016:
Genus Batiacasphaera Drugg, 1970 emend. nov.
Type: Batiacasphaera compta Drugg, 1970.
1970 Batiacasphaera Drugg, p. 813.
1975 Batiacasphaera Drugg, 1970 emend. Morgan, p. 161.
1980 Batiacasphaera Drugg, 1970 emend.Dörhöfer and Davies, p. 40.
Original diagnosis: Tract spherical to subspherical with an angular apical archaeopyle. The ornamentation consists of rod–shaped elements, either separate or arranged to form a reticulum. In the latter case, they may be fused (Drugg, 1970, p. 813).
Emended diagnosis: Proximate, acavate gonyaulacalean dinoflagellate cysts with a subspheroidal to ovoidal central body in dorso-ventral view. The autophragm bears nontabulate ornament that is rugulate to reticulate, or isolated elements that align. The archaeopyle is apical, with a free operculum.
Emended description: Small to intermediate, acavate, proximate dinoflagellate cysts that are subspherical to ovoidal in shape, occasionally elongate. The autophragm is generally thick and bears a rugulate to reticulate ornament, or bears typically rod-shaped elements that are arranged, or may fuse, to forma reticulumor polygonal, semi-polygonal or rugulate pattern. The presumed gonyaulacacean tabulation is only indicated by the apical archaeopyle, which normally has a free operculum. Typically, accessory archaeopyle sutures are not, or only weakly, developed, but may be better developed in some species. The cingulum and sulcus are not indicated.
Comments: Morgan (1975, p. 161) gave an emended description for Batiacasphaera in which he noted the lenticular shape and that the ornamentational elements may fuse to form rugulae. We consider the shape to be more subspheroidal than lenticular, but do accept forms in Batiacasphaera with linear ornament consisting of fused elements. Dörhöfer and Davies (1980, p. 40) indicated that they were emending Batiacasphaera but provided neither an emended diagnosis or description nor a clear statement of their generic concept.
We restrict Batiacasphaera to species within the Sentusidinium complex that have a generally reticulate to rugulate ornamentation. Drugg (1970) originally diagnosed Batiacasphaera as having an “angular apical archaeopyle”, implying that the accessory archaeopyle sutures between precingular plates are absent or weakly developed. We found that across the Sentusidinium complexes, using this feature as a defining one at generic level was very difficult to apply. So we re-assign species similar to the type in terms of accessory archaeopyle suture development, such as Batiacasphaera baculata, but with isolated, non-aligned sculptural elements, to Sentusidinium. The lack ofwell-developed accessory archaeopyle sutures can give the superficial impression of a precingular archaeopyle, especially in poorly preserved or obliquely oriented specimens; however, closer examination of better specimens reveals the shape of an apical archaeopyle. The holotype of Batiacasphaera compta, the type of Batiacasphaera, shows an unconventional outline to its archaeopyle and is thus difficult to interpret precisely in terms of tabulation. However, other specimens of Batiacasphaera compta, and other species of the genus show a conventional type (tA) archaeopyle. Fensome and Williams (2004, p. 73–78) listed 49 species of Batiacasphaera. However, only 17 of these species have a rugulate to reticulate
autophragm, and these are all Early Cretaceous to Late Miocene in age. They are listed below in the accepted species list and summarised in Table 1.
Comparison: Batiacasphaera differs from all three other genera in the Sentusidinium complex by its strongly developed reticulate to regulate ornamentation.