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Gonyaulacysta plea
Gonyaulacysta? plea (Tasch, 1964) Lentin and Williams, 1976
Now Deflandrea?. Originally Peridinium, subsequently (and now) Deflandrea?, thirdly Gonyaulacysta?. At the time of the transfer, Lentin and Williams, 1976, questionably included this species in Gonyaulacysta. Stover and Evitt (1978, p.101) retained this species in Deflandrea.
Holotype: Tasch, 1964, pl.1, fig.15
Age: Albian
(Tasch, 1964)
Diagnosis: Full, spherical theca, bearing a brief, apical horn, and very broad antapical horns. Epithecal plate system partially defined, but apical plates unclear and hypothecal plates not distinguishable. Broad, dark, central band which loops around anteriorly is a contracted cyst. Epitheca gently tapered apically, an about twice as large as hypotheca.
Measurements: lenth, excluding apical horn, 68 µm; width, 62 µm; width of girdle, 5 µm; length of apical horn, 6 µm.
Discussion: Living species assigned to the genus Peridinium embrace a wide range of morphologies. Fossil species assigned to this genus are generally less variable in morphology. This new species describes herein is unlike any previously assigned to this genus in the nature of antapical horns and the more spherical configuration. It is strictly different from P. kansanum Tasch, n. sp. (plate 1, figure 1).
Holotype: WU-DF 0163. Slide no. 1016. Coordinates: R 29, D 15.5+
Locality: Sampling interval 4-1-H.
Now Deflandrea?. Originally Peridinium, subsequently (and now) Deflandrea?, thirdly Gonyaulacysta?. At the time of the transfer, Lentin and Williams, 1976, questionably included this species in Gonyaulacysta. Stover and Evitt (1978, p.101) retained this species in Deflandrea.
Holotype: Tasch, 1964, pl.1, fig.15
Age: Albian
(Tasch, 1964)
Diagnosis: Full, spherical theca, bearing a brief, apical horn, and very broad antapical horns. Epithecal plate system partially defined, but apical plates unclear and hypothecal plates not distinguishable. Broad, dark, central band which loops around anteriorly is a contracted cyst. Epitheca gently tapered apically, an about twice as large as hypotheca.
Measurements: lenth, excluding apical horn, 68 µm; width, 62 µm; width of girdle, 5 µm; length of apical horn, 6 µm.
Discussion: Living species assigned to the genus Peridinium embrace a wide range of morphologies. Fossil species assigned to this genus are generally less variable in morphology. This new species describes herein is unlike any previously assigned to this genus in the nature of antapical horns and the more spherical configuration. It is strictly different from P. kansanum Tasch, n. sp. (plate 1, figure 1).
Holotype: WU-DF 0163. Slide no. 1016. Coordinates: R 29, D 15.5+
Locality: Sampling interval 4-1-H.