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Alisocysta rugolirata
Alisocysta rugolirata, Damassa, 1979
Holotype: Damassa, 1979, pl.3, figs.7-13
Locus typicus: Fransiscan Complex, California, USA
Stratum typicum: Danian
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Original description: [Damassa, 1979, p. 193-194]:
Diagnosis:
Cyst spherical to subspherical; paratabulation indicated by low penitabular ridges. Accessory ridges commonly developed more or less parallel to the penitabular ridges. Penitabular and accessory ridges have a distinctly crinkled appearance.
Archeopyle Type (tA).
Description:
Cyst spherical to subspherical, 38-50 µm in diameter; length generally slightly greater than width.
Paratabulation indicated by thin, transparent penitabular ridges 2-4 µm in height, bearing minute protrusions which give the ridges a distinctly crinkled appearance. Discontinuous accessory ridges are more or less parallel to the penitabular ridges, and are commonly developed on large pre- and postcingular paraplates. Surface of cyst generally smooth, but may have slight irregularities.
Archeopyle Type (tA); operculum free, but not observed.
Parasulcal notch on ventral surface well-developed. Precingular paraplates 1"-5 " similar in size, sixth precingular paraplate slightly reduced in size with respect to 1"-5 ". Cingular paraplates indicated by penitabular ridges having a rectangular outline. Postcingular paraplate series completely developed; 3"""-5""" large, 2""" and 6""" are smaller and 1""" is greatly reduced in size relative to the other paraplates in the series. Sulcal paraplates also completely delineated. Antapical paraplate pentagonal, bordered by 1p, 3""", 4""", 5""", ps; not in contact with 6""".
Paratabulation: ?pr, ?4", 6"", 6c, 5s, 1p, 6""", 1"""". Inferred thecal tabulation: ?pr, ?4", 6"", 6c, 5s, 1p, 6""", 1"""".
Affinities:
Alisocysta rugolirata closely resembles A. circumtabulata (Drugg) Stover and Evitt 1978 but differs in the presence of additional ridges on the large dorsal paraplates. In addition A. rugolirata is characterized by the distinctly crinkled appearance of the penitabular and additional ridges, whereas in A. circumtabulata the penitabular ridges are conspicuously smooth and free of irregularities.
Holotype: Damassa, 1979, pl.3, figs.7-13
Locus typicus: Fransiscan Complex, California, USA
Stratum typicum: Danian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Damassa, 1979, p. 193-194]:
Diagnosis:
Cyst spherical to subspherical; paratabulation indicated by low penitabular ridges. Accessory ridges commonly developed more or less parallel to the penitabular ridges. Penitabular and accessory ridges have a distinctly crinkled appearance.
Archeopyle Type (tA).
Description:
Cyst spherical to subspherical, 38-50 µm in diameter; length generally slightly greater than width.
Paratabulation indicated by thin, transparent penitabular ridges 2-4 µm in height, bearing minute protrusions which give the ridges a distinctly crinkled appearance. Discontinuous accessory ridges are more or less parallel to the penitabular ridges, and are commonly developed on large pre- and postcingular paraplates. Surface of cyst generally smooth, but may have slight irregularities.
Archeopyle Type (tA); operculum free, but not observed.
Parasulcal notch on ventral surface well-developed. Precingular paraplates 1"-5 " similar in size, sixth precingular paraplate slightly reduced in size with respect to 1"-5 ". Cingular paraplates indicated by penitabular ridges having a rectangular outline. Postcingular paraplate series completely developed; 3"""-5""" large, 2""" and 6""" are smaller and 1""" is greatly reduced in size relative to the other paraplates in the series. Sulcal paraplates also completely delineated. Antapical paraplate pentagonal, bordered by 1p, 3""", 4""", 5""", ps; not in contact with 6""".
Paratabulation: ?pr, ?4", 6"", 6c, 5s, 1p, 6""", 1"""". Inferred thecal tabulation: ?pr, ?4", 6"", 6c, 5s, 1p, 6""", 1"""".
Affinities:
Alisocysta rugolirata closely resembles A. circumtabulata (Drugg) Stover and Evitt 1978 but differs in the presence of additional ridges on the large dorsal paraplates. In addition A. rugolirata is characterized by the distinctly crinkled appearance of the penitabular and additional ridges, whereas in A. circumtabulata the penitabular ridges are conspicuously smooth and free of irregularities.