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Ceratiopsis cordifera
Ceratiopsis cordifera, (May, 1980), Lentin and Williams, 1981
Combination illegitimate since the generic name Ceratiopsis is illegitimate.
Now Cerodinium. Originally Deflandrea, subsequently Ceratiopsis (combination illegitimate), thirdly (and now) Cerodinium.
Holotype: May, 1980, pl.8, fig.4
Locus typicus: Atlantic Highlands, New Jersey
Stratum typicum: Sandy Hook Member of Red Bank Sand, Maastrichtian
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Original description as Deflandrea cordifera: [May, 1980, p.74-75]:
Description:
Cyst triangular in outline; slightly expanded at cingulum; bearing long, slender, equal, gently-tapering, irregularly-striate, sharp-tipped, apical and antapical horns, measuring ca. 1/2-2/3 central body length; antapical horns diverging. Central body occupies most of cyst interior, extending a few microns into apical and antapical horn cavities, imparting a somewhat inverted heart-shaped appearance. Cyst dorso-ventrally flattened. Periphragm longitudinally striate, striae continuing to tips of horns; nontabulate.
Endophragm smooth; closely appressed to periphragm, except within the horns where long pericoels are developed.
Cingulum formed of parallel, discontinuous, equatorial folds in periphragm; bears numerous, closely spaced, vertical striae; levorotatory offset ca. 1/2 cingulum width.
Sulcus outlined by low folds in periphragm, beginning between terminal ends of cingulum, broadening posteriorly to tips of antapical horns.
Archeopyle intercalary (Type I/I); large, occupying ca. 2/3 or more of medial dorsal epitract; excystment opening in endophragm of similar shape and size.
Dimensions:
Holotype L x W, 160 x 70 µm, apical horn from apex of endoblast 43 µm, antapical horns from anatpex of endoblast 32 µm Observed range (15 specimens measured): length 158-186 µm, width 63-70 µm; apical horns ca. 1/2 to 2/3 central body length; wall layers ca. 1 µm, each of similar thickness.
Discussion/Affinities:
The most diagnostic feature is general shape of periblast and endoblast. The roughly triangular periblast with slightly convex-outward lateral margins and long, slender, pointed apical and antapical horns are distinctive. The inverted, heart-shaped endoblast sets it apart from similar species, e.g., D. diebeli Alberi 1959, and D. striata Drugg 1967.
Affinities:
Monmouth Group specimens are somewhat similar to D. diebeli Alberti 1959 (p. 99, pl. 9, figs. 18--21); however, are distinctive in being less striate, having generally shorter apical and antapical horns from antapex of endoblast 32 µm. Observed range D. diebeli is narrower in appearance in the hypotract area. D. cordifera differs from D. striata Drugg 1967 by having an inverted heart-shaped endoblast.
Combination illegitimate since the generic name Ceratiopsis is illegitimate.
Now Cerodinium. Originally Deflandrea, subsequently Ceratiopsis (combination illegitimate), thirdly (and now) Cerodinium.
Holotype: May, 1980, pl.8, fig.4
Locus typicus: Atlantic Highlands, New Jersey
Stratum typicum: Sandy Hook Member of Red Bank Sand, Maastrichtian
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Original description as Deflandrea cordifera: [May, 1980, p.74-75]:
Description:
Cyst triangular in outline; slightly expanded at cingulum; bearing long, slender, equal, gently-tapering, irregularly-striate, sharp-tipped, apical and antapical horns, measuring ca. 1/2-2/3 central body length; antapical horns diverging. Central body occupies most of cyst interior, extending a few microns into apical and antapical horn cavities, imparting a somewhat inverted heart-shaped appearance. Cyst dorso-ventrally flattened. Periphragm longitudinally striate, striae continuing to tips of horns; nontabulate.
Endophragm smooth; closely appressed to periphragm, except within the horns where long pericoels are developed.
Cingulum formed of parallel, discontinuous, equatorial folds in periphragm; bears numerous, closely spaced, vertical striae; levorotatory offset ca. 1/2 cingulum width.
Sulcus outlined by low folds in periphragm, beginning between terminal ends of cingulum, broadening posteriorly to tips of antapical horns.
Archeopyle intercalary (Type I/I); large, occupying ca. 2/3 or more of medial dorsal epitract; excystment opening in endophragm of similar shape and size.
Dimensions:
Holotype L x W, 160 x 70 µm, apical horn from apex of endoblast 43 µm, antapical horns from anatpex of endoblast 32 µm Observed range (15 specimens measured): length 158-186 µm, width 63-70 µm; apical horns ca. 1/2 to 2/3 central body length; wall layers ca. 1 µm, each of similar thickness.
Discussion/Affinities:
The most diagnostic feature is general shape of periblast and endoblast. The roughly triangular periblast with slightly convex-outward lateral margins and long, slender, pointed apical and antapical horns are distinctive. The inverted, heart-shaped endoblast sets it apart from similar species, e.g., D. diebeli Alberi 1959, and D. striata Drugg 1967.
Affinities:
Monmouth Group specimens are somewhat similar to D. diebeli Alberti 1959 (p. 99, pl. 9, figs. 18--21); however, are distinctive in being less striate, having generally shorter apical and antapical horns from antapex of endoblast 32 µm. Observed range D. diebeli is narrower in appearance in the hypotract area. D. cordifera differs from D. striata Drugg 1967 by having an inverted heart-shaped endoblast.