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Apteodinium deflandrei
Apteodinium deflandrei, (Clarke and Verdier, 1967); Emend. Lucas-Clark, 1987
Originally Gardodinium, subsequently Aldorfia, thirdly (and now) Apteodinium
Holotype: Clarke and Verdier, 1967, pl.3, fig.10; Jan du Chêne et al., 1986, pl.8, figs.10-11
Locus typicus: Isle of Wight, Culver Cliff; England
Stratum typicum: Senonian
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Original description as Gardodinium deflandrei: [Clarke and Verdier, 1967, p. 26]:
Diagnosis:
A species of Gardodinium without an apical protrusion of the inner body, with closely spaced pillars supporting the outer wall, and a precingular archaeopyle.
Description:
Inner body round, connected with a thin outer wall by means of pillars. Pillars more or less equal in length, joining distally or more proximally to give a rugulate pattern (text-fig. 10). This pillar-pattern is present over the whole of the inner body and is extended apically to form a horn. At this point the pillars are not in contact with the apical part of the inner body.
A distinct arch-shaped archaeopyle is present and is precingular in position; such a feature is observed on about 90 % of the specimens.
A girdle is present and can best be seen when viewed on edge of the outline; ventrally the displacement equals two girdle widths. In many specimens a longitudinal furrow, extended equally on both epitheca and hypotheca, can be observed.
There is no tabulation.
Dimensions:
Holotype: Overall length 52 µm, overall breadth 40 µm, length of inner body 36 µm, breadth of inner body 34 µm, length of apical horn 8 µm, length of pillars 1.5-4 µm.
Range: Overall length 52-56 µm, overall breadth 40-48 µm, length of inner body 36-43 µm, breadth of inner body 34-41 µm, length of apical horn 8-10 µm, length of pillars 1.5-4.5 µm.
Affinities:
G. deflandrei differs from G. eisenacki Alberti in the absence of an apical protrusion on the inner body and from G. trabeculosum Alberti 1961 and G. albertii Neale and Sarjeant 1962 in the more closely spaced pillars.
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Emended description:
Lucas-Clarke, 1987, p. 173:
Description:
Intermediate to large, acavate, oval to subpolygonal cysts with well-developed, long apical horn (about 1/4 overall length of cyst).
Wall consists of an inner layer almost completely covered with a spongy, cavernous material. The outer surface of the spongy, cavernous material can be regarded as an outer layer which is perforate. Exterior surface of cyst perforate, wrinkled, and ridged, giving cyst a rugulate appearance. Cingulum marked by low ridges and slight depression.
Sulcus marked by relatively low ornamentation.
Outline in dorsal-ventral view varies from subspherical to oval to subpolygonal. Outline in apical view circular with slight sulcal indentation.
Paratabulation may be visible only with scanning electron microscopy due to obscuring effect of complex wall structure. Parasutures marked by ridges and depressions in the outer wall surface, or by traces of ornament. Paratabulation as described for genus. Antapical paraplate (Y) strongly asymmetrical and narrow, and positioned partly on the ventral side of cyst. The IV/V/Y triple junction lies at the mid-dorsal antapex and forms a slight antapical protrusion.
Specimen studied with SEM shows traces of wide growth bands marked by accessory ridges on pre- and postcingular paraplates.
Affinities:
Remarks: Scanning electron microscopy of this species shows that its wall is thicker than, but quite similar in structure to, that of specimens identified as A. granulatum, the type species of Apteodinium. Its paratabulation pattern is more closely similar to that of Apteodinium granulatum than it is to Aldorfa aldorfensis, the type species of Aldorfa, to which Apteodinium deflandrei was previously assigned on the basis of wall structure. A. deflandrei shows no evidence of the presence of a Q paraplate, and has a more rounded, rather than angular or rhomboidal, overall cyst shape than species of Aldorf a.
Comparison: Other species of Apteodinium differ from A. deflandrei in having either a thinner, smoother wall (e.g., A. apiatum), or in having a thicker, more complex and extensive spongy, cavernous material forming the wall (e.g., A. spiridoides). The apical horn of A. deflandrei is longer and more prominent than is typical for species of Apteodinium.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP
Apteodinium deflandrei (Clarke and Verdier, 1967) Lucas-Clark, 1987, emend. Lucas-Clark, 1987. From Lucas-Clark (1987, p. 173). Intermediate to large acavate, oval to subpolygonal cysts with well-developed, long apical horn (about 1/4 overall length of cyst). Wall consists of an inner layer almost completely covered with a spongy, cavernous material. The outer surface of the spongy, cavernous material can be regarded as an outer layer which is perforate. Exterior surface of cyst perforate, wrinkled, and ridged, giving cyst a rugulate appearance. Cingulum marked by low ridges and slight depression. Sulcus marked by relatively low ornamentation. Outline in dorsal-ventral view varies from subspherical to oval to subpolygonal. Outline in apical view circular with slight sulcal indentation. Paratabulation may be visible only under the scanning electron microscope, due to the obscuring effect of the complex wall structure. Parasutures marked by ridges and depressions in the outer wall surface, or by traces of ornament. Antapical paraplate strongly asymmetrical and narrow, and partly on the ventral surface. Growth bands and accessory ridges visible under SEM.
Size: length 52-56 µm, width 40-48 µm.
Originally Gardodinium, subsequently Aldorfia, thirdly (and now) Apteodinium
Holotype: Clarke and Verdier, 1967, pl.3, fig.10; Jan du Chêne et al., 1986, pl.8, figs.10-11
Locus typicus: Isle of Wight, Culver Cliff; England
Stratum typicum: Senonian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Gardodinium deflandrei: [Clarke and Verdier, 1967, p. 26]:
Diagnosis:
A species of Gardodinium without an apical protrusion of the inner body, with closely spaced pillars supporting the outer wall, and a precingular archaeopyle.
Description:
Inner body round, connected with a thin outer wall by means of pillars. Pillars more or less equal in length, joining distally or more proximally to give a rugulate pattern (text-fig. 10). This pillar-pattern is present over the whole of the inner body and is extended apically to form a horn. At this point the pillars are not in contact with the apical part of the inner body.
A distinct arch-shaped archaeopyle is present and is precingular in position; such a feature is observed on about 90 % of the specimens.
A girdle is present and can best be seen when viewed on edge of the outline; ventrally the displacement equals two girdle widths. In many specimens a longitudinal furrow, extended equally on both epitheca and hypotheca, can be observed.
There is no tabulation.
Dimensions:
Holotype: Overall length 52 µm, overall breadth 40 µm, length of inner body 36 µm, breadth of inner body 34 µm, length of apical horn 8 µm, length of pillars 1.5-4 µm.
Range: Overall length 52-56 µm, overall breadth 40-48 µm, length of inner body 36-43 µm, breadth of inner body 34-41 µm, length of apical horn 8-10 µm, length of pillars 1.5-4.5 µm.
Affinities:
G. deflandrei differs from G. eisenacki Alberti in the absence of an apical protrusion on the inner body and from G. trabeculosum Alberti 1961 and G. albertii Neale and Sarjeant 1962 in the more closely spaced pillars.
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Emended description:
Lucas-Clarke, 1987, p. 173:
Description:
Intermediate to large, acavate, oval to subpolygonal cysts with well-developed, long apical horn (about 1/4 overall length of cyst).
Wall consists of an inner layer almost completely covered with a spongy, cavernous material. The outer surface of the spongy, cavernous material can be regarded as an outer layer which is perforate. Exterior surface of cyst perforate, wrinkled, and ridged, giving cyst a rugulate appearance. Cingulum marked by low ridges and slight depression.
Sulcus marked by relatively low ornamentation.
Outline in dorsal-ventral view varies from subspherical to oval to subpolygonal. Outline in apical view circular with slight sulcal indentation.
Paratabulation may be visible only with scanning electron microscopy due to obscuring effect of complex wall structure. Parasutures marked by ridges and depressions in the outer wall surface, or by traces of ornament. Paratabulation as described for genus. Antapical paraplate (Y) strongly asymmetrical and narrow, and positioned partly on the ventral side of cyst. The IV/V/Y triple junction lies at the mid-dorsal antapex and forms a slight antapical protrusion.
Specimen studied with SEM shows traces of wide growth bands marked by accessory ridges on pre- and postcingular paraplates.
Affinities:
Remarks: Scanning electron microscopy of this species shows that its wall is thicker than, but quite similar in structure to, that of specimens identified as A. granulatum, the type species of Apteodinium. Its paratabulation pattern is more closely similar to that of Apteodinium granulatum than it is to Aldorfa aldorfensis, the type species of Aldorfa, to which Apteodinium deflandrei was previously assigned on the basis of wall structure. A. deflandrei shows no evidence of the presence of a Q paraplate, and has a more rounded, rather than angular or rhomboidal, overall cyst shape than species of Aldorf a.
Comparison: Other species of Apteodinium differ from A. deflandrei in having either a thinner, smoother wall (e.g., A. apiatum), or in having a thicker, more complex and extensive spongy, cavernous material forming the wall (e.g., A. spiridoides). The apical horn of A. deflandrei is longer and more prominent than is typical for species of Apteodinium.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP
Apteodinium deflandrei (Clarke and Verdier, 1967) Lucas-Clark, 1987, emend. Lucas-Clark, 1987. From Lucas-Clark (1987, p. 173). Intermediate to large acavate, oval to subpolygonal cysts with well-developed, long apical horn (about 1/4 overall length of cyst). Wall consists of an inner layer almost completely covered with a spongy, cavernous material. The outer surface of the spongy, cavernous material can be regarded as an outer layer which is perforate. Exterior surface of cyst perforate, wrinkled, and ridged, giving cyst a rugulate appearance. Cingulum marked by low ridges and slight depression. Sulcus marked by relatively low ornamentation. Outline in dorsal-ventral view varies from subspherical to oval to subpolygonal. Outline in apical view circular with slight sulcal indentation. Paratabulation may be visible only under the scanning electron microscope, due to the obscuring effect of the complex wall structure. Parasutures marked by ridges and depressions in the outer wall surface, or by traces of ornament. Antapical paraplate strongly asymmetrical and narrow, and partly on the ventral surface. Growth bands and accessory ridges visible under SEM.
Size: length 52-56 µm, width 40-48 µm.