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Palaeocystodinium bulliforme
Palaeocystodinium bulliforme Ioannides, 1986
synonym: 1971 ?Svalbardella sp. in Wilson, Pl. 2, fig. 14.
Holotype: Ioannides 1986: Plate 17, figure 4
Locus typicus: Eureka Sound Formation, South Coast section, Bylot Island, District of Franklin, Cananda.
Stratum typicum: Paleocene.
Age: Paleocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Palaeocystodinium bulliforme Ioannides, 1986. Palaeocystodinium bulliforme is cornucavate to circumcavate, endocyst distinctly turgid, ellipsoidal to subspherical. Apical and antapical horns broad-based, having pointed or rounded distal ends. No parasutural features observed. No paracingulum or parasulcus. The specimens of Wilson (1971, pl.2, fig.14) and Williams and Brideaux (1975, Pl.10, fig.3) are assignable to this species. Size: length 179-240 µm, breadth 64-120 µm. Endocyst; length 80-125 µm, breadth 60-102 µm
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Diagnosis: Ioannides 1986, p. 31
Cyst proximate, cornucavate to circumcavate; endocyst distinctly turgid, ellipsoidal to subspherical. Apical and antapical horns broad based, having pointed or rounded distal ends. No parasutural features observed. Archeopyle intercalary, type I (2a only). Paracingulum and parasulcus not indicated.
Description: Ioannides 1986, p. 31
Shape elongate, subspherical to ellipsoidal, often found in lateral orientation. Endocyst conforms to pericyst in general shape.
Wall: Apical and antapical horns broad based with pointed or rounded distal ends, often surmounted by a spine more frequently seen on apical horn. Cyst cornucavate to circumcavate; pericoel greater at horn bases, can be indiscernible along remainder of cyst. No parasutural features observed. Periphragm smooth to finely granular. Endophragm thin, smooth and highly folded. An offset indentation or spur may occur on antapical horn.
Paratabulation: indicated by archeopyle only.
Archeopyle: occasionally developed; intercalary, type I (2a only), apparently involves only periphragm; height greater than width, narrowly rounded apically or distinctly hexagonal. Operculum free or attached, often along its base, but sometimes elsewhere.
Paracingulum and parasulcus not indicated
Dimensions:
Holotype: Pericyst length, 226 µm, pericyst width, 91 µm
Range: Total length (excluding end spine) 179-240 µm, total width 64- 120 µm; endocyst 80- 125 µm long, 60-102µm wide; end spine up to 7 µm high; pericoel up to 6 µm wide but attains maximum width at horn bases, 28 µm; periphragm 1.5 µm, or less, in thickness (25 specimens measured).
Comparison and remarks:
The shape of the endocyst and horns distinguish this species from others of the genus. The specimens illustrated by Wilson (1971, Pl. 2, fig. 14), and subsequently by Williams and Brideaux (1975, Pl. 10, fig. 3) are considered to belong to P. bulliformum sp. nov. Palaeocystodinium stockmansii Boltenhagen, 1977 has a more elongate endocyst, shorter horns and generally smaller size. Palaeocystodinium sp. aff. P. golzowense in Boltenhagen (1977, Pl. 23, figs. 5-8), is similar in gross morphology, but with considerably narrower horns and a more elongate endocyst.
synonym: 1971 ?Svalbardella sp. in Wilson, Pl. 2, fig. 14.
Holotype: Ioannides 1986: Plate 17, figure 4
Locus typicus: Eureka Sound Formation, South Coast section, Bylot Island, District of Franklin, Cananda.
Stratum typicum: Paleocene.
Age: Paleocene
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Palaeocystodinium bulliforme Ioannides, 1986. Palaeocystodinium bulliforme is cornucavate to circumcavate, endocyst distinctly turgid, ellipsoidal to subspherical. Apical and antapical horns broad-based, having pointed or rounded distal ends. No parasutural features observed. No paracingulum or parasulcus. The specimens of Wilson (1971, pl.2, fig.14) and Williams and Brideaux (1975, Pl.10, fig.3) are assignable to this species. Size: length 179-240 µm, breadth 64-120 µm. Endocyst; length 80-125 µm, breadth 60-102 µm
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Diagnosis: Ioannides 1986, p. 31
Cyst proximate, cornucavate to circumcavate; endocyst distinctly turgid, ellipsoidal to subspherical. Apical and antapical horns broad based, having pointed or rounded distal ends. No parasutural features observed. Archeopyle intercalary, type I (2a only). Paracingulum and parasulcus not indicated.
Description: Ioannides 1986, p. 31
Shape elongate, subspherical to ellipsoidal, often found in lateral orientation. Endocyst conforms to pericyst in general shape.
Wall: Apical and antapical horns broad based with pointed or rounded distal ends, often surmounted by a spine more frequently seen on apical horn. Cyst cornucavate to circumcavate; pericoel greater at horn bases, can be indiscernible along remainder of cyst. No parasutural features observed. Periphragm smooth to finely granular. Endophragm thin, smooth and highly folded. An offset indentation or spur may occur on antapical horn.
Paratabulation: indicated by archeopyle only.
Archeopyle: occasionally developed; intercalary, type I (2a only), apparently involves only periphragm; height greater than width, narrowly rounded apically or distinctly hexagonal. Operculum free or attached, often along its base, but sometimes elsewhere.
Paracingulum and parasulcus not indicated
Dimensions:
Holotype: Pericyst length, 226 µm, pericyst width, 91 µm
Range: Total length (excluding end spine) 179-240 µm, total width 64- 120 µm; endocyst 80- 125 µm long, 60-102µm wide; end spine up to 7 µm high; pericoel up to 6 µm wide but attains maximum width at horn bases, 28 µm; periphragm 1.5 µm, or less, in thickness (25 specimens measured).
Comparison and remarks:
The shape of the endocyst and horns distinguish this species from others of the genus. The specimens illustrated by Wilson (1971, Pl. 2, fig. 14), and subsequently by Williams and Brideaux (1975, Pl. 10, fig. 3) are considered to belong to P. bulliformum sp. nov. Palaeocystodinium stockmansii Boltenhagen, 1977 has a more elongate endocyst, shorter horns and generally smaller size. Palaeocystodinium sp. aff. P. golzowense in Boltenhagen (1977, Pl. 23, figs. 5-8), is similar in gross morphology, but with considerably narrower horns and a more elongate endocyst.