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Moesiodinium raileanui
Moesiodinium raileanui Antonescu, 1974
Holotype: Antonescu 1974, pl.1, fig.5-8,10-12
Paratype: Antonescu 1974
Locus typicus: Salcia Well, Moesian platform, Romania
Stratum typicum: Middle Jurassic
Translation Antonescu, 1974: LPP
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Moesiodinium raileanui Antonesçu, 1974, has a cingulum and sulcus. The only indication of tabulation is the archeopyle. Bjaerke (1980) stated that the endocyst could vary from circular to triangular, and the pericyst could be ovoidal to triangular with a somewhat pointed apex. The holotype is 32 µm in length and the endocyst 25 µm.
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Original Description: Antonescu 1974, p. 62-63
Dinoflagellate with a rounded or oval capsule (cavate sensu Williams and Downie in: Davey, Downie, Sarjeant and Williams, 1966), more pointes towards the apex, and presenting the tendency to form two smal appendices at the the antapex.
The rounded or oval capsule (central body, inner body, sensu Evitt in Tschudy and Scott, 1969) occupies the largest part of the theca and the periphragm envelops it entirely, uniformly, the capsule occupying a central position. The capsule is ornamented with small, irrgularly distributed granulae (1 micron). The capsule is possibly formed by two layers, considering its thickness, which is larger than that of the periphragm.
An equatorial furrow (cingulum), visible on the dorsal and ventral surfaces, divides the theca in two, more or less equal parts. The epitheca is slightly larger than the hypotheca. A longitudinal furrow is vaguely visible on the ventral surface; here one can observe that the equatorial (or transverse) furrow is dextrorotatory.
The periphragm (external layer) is very thin, and shows folds.
The archaeopyle has a dorsal, intercalary position, and is hexagonal.There are no other traces of tabulation. The tabulation, illustrated only by the archaeopyle, could by peridinean. The archaeopyle seems to be formed by the loss of plate 2a (second anterior intercalary) and to be present only in the periphragm, not in the capsule (archaeopyle 1b-3 of Evitt 1967?). The hexagonal plate of the archeopyle always has one corner of the hexagon directed towards the cingulum. At first sight, the archaeopyle seemed to be pentagonal, but a closer inspection shows that the plate is hexagonal; this is also the case in the holotype. The operculum is free, simple, and seems to have the same form as plate 2a.
With its yellow, bright transparent colour, the central body appears darker, due to the greater thickness.
Dimensions: Holotype: Length 34 Ám, width 32 Ám, capsule 25 Ám.
Below, 1987, p. 130:
Remark: The narrow, indented cingulum is planar to weakly laevorotatory, and not dextrospiral, as it was stated in the original diagnosis.
Holotype: Antonescu 1974, pl.1, fig.5-8,10-12
Paratype: Antonescu 1974
Locus typicus: Salcia Well, Moesian platform, Romania
Stratum typicum: Middle Jurassic
Translation Antonescu, 1974: LPP
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Moesiodinium raileanui Antonesçu, 1974, has a cingulum and sulcus. The only indication of tabulation is the archeopyle. Bjaerke (1980) stated that the endocyst could vary from circular to triangular, and the pericyst could be ovoidal to triangular with a somewhat pointed apex. The holotype is 32 µm in length and the endocyst 25 µm.
--------------------------------------------------
Original Description: Antonescu 1974, p. 62-63
Dinoflagellate with a rounded or oval capsule (cavate sensu Williams and Downie in: Davey, Downie, Sarjeant and Williams, 1966), more pointes towards the apex, and presenting the tendency to form two smal appendices at the the antapex.
The rounded or oval capsule (central body, inner body, sensu Evitt in Tschudy and Scott, 1969) occupies the largest part of the theca and the periphragm envelops it entirely, uniformly, the capsule occupying a central position. The capsule is ornamented with small, irrgularly distributed granulae (1 micron). The capsule is possibly formed by two layers, considering its thickness, which is larger than that of the periphragm.
An equatorial furrow (cingulum), visible on the dorsal and ventral surfaces, divides the theca in two, more or less equal parts. The epitheca is slightly larger than the hypotheca. A longitudinal furrow is vaguely visible on the ventral surface; here one can observe that the equatorial (or transverse) furrow is dextrorotatory.
The periphragm (external layer) is very thin, and shows folds.
The archaeopyle has a dorsal, intercalary position, and is hexagonal.There are no other traces of tabulation. The tabulation, illustrated only by the archaeopyle, could by peridinean. The archaeopyle seems to be formed by the loss of plate 2a (second anterior intercalary) and to be present only in the periphragm, not in the capsule (archaeopyle 1b-3 of Evitt 1967?). The hexagonal plate of the archeopyle always has one corner of the hexagon directed towards the cingulum. At first sight, the archaeopyle seemed to be pentagonal, but a closer inspection shows that the plate is hexagonal; this is also the case in the holotype. The operculum is free, simple, and seems to have the same form as plate 2a.
With its yellow, bright transparent colour, the central body appears darker, due to the greater thickness.
Dimensions: Holotype: Length 34 Ám, width 32 Ám, capsule 25 Ám.
Below, 1987, p. 130:
Remark: The narrow, indented cingulum is planar to weakly laevorotatory, and not dextrospiral, as it was stated in the original diagnosis.