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Eisenackia chilensis
Eisenackia chilensis Quattrocchio and Sarjeant, 2003, p.146, fig.3a-d, fig.7B-C, fig.10A-B.
Holotype: Quattrocchio and Sarjeant, 2003, fig.3c-d, fig.7B-C.
Age: Paleocene.
Original description, Quattrocchio and Sarjeant, 2003: Eisenackia chilensis sp. nov. (Figures 3, 7.B-C and 10.A-B)
Derivatio nominis: Of Chile, in reference to the source of the specimen.
Diagnosis: A species of Eisenackia having a subsphaerical to ovoidal cyst; tabulation indicated by low penitabular ridges with beaded bases. Intratabular ornamentation with few to more or less densely distributed coni. Archeopyle type (tA); operculum free.
Description: Cyst proximochorate subsphaerical to ovoidal. Tabulation indicated by thin, transparent penitabular ridges (3 µm in height). The phragm is up to 2 µm thick, only the periphragm making up the penitabular membranes. Contact between the membranes and phragm is marked by thickenings in the periphragm, which in optical section give the appearance of beads. Intratabular ornamentations of coni (up to 3 µm in height), sparsely (3 to 4 per peniplate) to more or less densely (8 to 10) distributed. Sulcal notch well developed. Plate 6’’ is reduced with respect to others in the precingular series. Cingular plates indicated by elongate, subrectangular penitabular ridges. Postcingular plates completely developed, although plate 1’’’is small and inconspicuous. Five sulcal plates indicated. Antapical plate pentagonal in shape, bordered by 1p, 3’’’, 4’’’, 5’’’, ps; pattern quinquiform. The sulcal includes the right sulcal and posterior sulcal homologues (Ii and Z). Archeopyle type (tA); operculum free and not observed.
Holotype: 3973/6: 19,9/129,9 (E30/3). Overall length: 54 µm, breadth: 42 µm.
Dimensions: Sample 2891/59: overall length 55 µm; breadth 55 µm. specimens 2893/59: overall length 47 µm; breadth 42 µm. 3973/6: 19,1/129,9 (E30/3): overall length 52 µm; breadth 42 µm.
Remarks: The most similar species is Eisenackia reticulate, which is differentiated from E. chilensis by its reticulate ornament.
Holotype: Quattrocchio and Sarjeant, 2003, fig.3c-d, fig.7B-C.
Age: Paleocene.
Original description, Quattrocchio and Sarjeant, 2003: Eisenackia chilensis sp. nov. (Figures 3, 7.B-C and 10.A-B)
Derivatio nominis: Of Chile, in reference to the source of the specimen.
Diagnosis: A species of Eisenackia having a subsphaerical to ovoidal cyst; tabulation indicated by low penitabular ridges with beaded bases. Intratabular ornamentation with few to more or less densely distributed coni. Archeopyle type (tA); operculum free.
Description: Cyst proximochorate subsphaerical to ovoidal. Tabulation indicated by thin, transparent penitabular ridges (3 µm in height). The phragm is up to 2 µm thick, only the periphragm making up the penitabular membranes. Contact between the membranes and phragm is marked by thickenings in the periphragm, which in optical section give the appearance of beads. Intratabular ornamentations of coni (up to 3 µm in height), sparsely (3 to 4 per peniplate) to more or less densely (8 to 10) distributed. Sulcal notch well developed. Plate 6’’ is reduced with respect to others in the precingular series. Cingular plates indicated by elongate, subrectangular penitabular ridges. Postcingular plates completely developed, although plate 1’’’is small and inconspicuous. Five sulcal plates indicated. Antapical plate pentagonal in shape, bordered by 1p, 3’’’, 4’’’, 5’’’, ps; pattern quinquiform. The sulcal includes the right sulcal and posterior sulcal homologues (Ii and Z). Archeopyle type (tA); operculum free and not observed.
Holotype: 3973/6: 19,9/129,9 (E30/3). Overall length: 54 µm, breadth: 42 µm.
Dimensions: Sample 2891/59: overall length 55 µm; breadth 55 µm. specimens 2893/59: overall length 47 µm; breadth 42 µm. 3973/6: 19,1/129,9 (E30/3): overall length 52 µm; breadth 42 µm.
Remarks: The most similar species is Eisenackia reticulate, which is differentiated from E. chilensis by its reticulate ornament.