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Impagidinium aquaeductum
Impagidinium aquaeductum (Piasecki, 1980) Lentin and Williams, 1985
Now Unipontidinium. Originally Nematosphaeropsis, subsequently Impagidinium, thirdly (and now) Unipontidinium.
Holotype: Piasecki, 1980, pl.1, fig.1-3
Locus typicus: Gram boring, Denmark
Stratum typicum: Middle Miocene
Original diagnosis: Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
A Nematosphaeropsis with short and stout processes connected distally by stout trabeculae, which are triangular in cross section. Parasutural structures are missing on the central body.
Original description: Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
Chorate cysts with spherical to slightly ovoidal central bodies and sutural processes and trabeculae forming an outer sphere. Only one wall layer is visible in the light microscope. No structures are visible in the wall. The surface is smooth or punctate. Gonal and intergonal processes are present and no parasutural structures connect the bases of the processes. A few of the processes show a small proximate cavity, otherwise they are massive and buccinate. The processes are short and stout, and angular in cross section. Distally they expand into connecting trabeculae, which make the paratabulation clearly visible. The trabeculae are triangular in coss section with one angle pointing against the capsule. The outer side of the trabeculae is concave, especially above the processes, giving rise to a shape similar to the shape of the roman aquaducts. The length of the processes are 9--12 µm, and uniform within a single specimen. The archaeopyle is formed by the loss of paraplate 3" and the operculum is completely detached. The archaeopyle formula is P. The paratabulation formula, determined from the arrangement of the trabeculae, is (4", 6", 6c, 5""", 1p, 1""""). Paracingulum is helicoidal.
Affinities:
Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
Nematosphaeropsis aquaeducta differs from other species of the genus Nematosphaeropsis by its short, simple and stout processes and trabeculae. Baltes (1969) figures a specimen identified as Nematosphaeropsis balcombiana Deflandre & Cookson, 1955. How ever, it appears from the figures that this specimen has the short and stout processes and trabeculae here used to define N. aquaeducta instead of the long and thin processes and trabeculae typical of N. balcombiana.
Now Unipontidinium. Originally Nematosphaeropsis, subsequently Impagidinium, thirdly (and now) Unipontidinium.
Holotype: Piasecki, 1980, pl.1, fig.1-3
Locus typicus: Gram boring, Denmark
Stratum typicum: Middle Miocene
Original diagnosis: Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
A Nematosphaeropsis with short and stout processes connected distally by stout trabeculae, which are triangular in cross section. Parasutural structures are missing on the central body.
Original description: Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
Chorate cysts with spherical to slightly ovoidal central bodies and sutural processes and trabeculae forming an outer sphere. Only one wall layer is visible in the light microscope. No structures are visible in the wall. The surface is smooth or punctate. Gonal and intergonal processes are present and no parasutural structures connect the bases of the processes. A few of the processes show a small proximate cavity, otherwise they are massive and buccinate. The processes are short and stout, and angular in cross section. Distally they expand into connecting trabeculae, which make the paratabulation clearly visible. The trabeculae are triangular in coss section with one angle pointing against the capsule. The outer side of the trabeculae is concave, especially above the processes, giving rise to a shape similar to the shape of the roman aquaducts. The length of the processes are 9--12 µm, and uniform within a single specimen. The archaeopyle is formed by the loss of paraplate 3" and the operculum is completely detached. The archaeopyle formula is P. The paratabulation formula, determined from the arrangement of the trabeculae, is (4", 6", 6c, 5""", 1p, 1""""). Paracingulum is helicoidal.
Affinities:
Piasecki, 1980, p. 70: Nematospheropsis aquaeducta
Nematosphaeropsis aquaeducta differs from other species of the genus Nematosphaeropsis by its short, simple and stout processes and trabeculae. Baltes (1969) figures a specimen identified as Nematosphaeropsis balcombiana Deflandre & Cookson, 1955. How ever, it appears from the figures that this specimen has the short and stout processes and trabeculae here used to define N. aquaeducta instead of the long and thin processes and trabeculae typical of N. balcombiana.