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Palaeoperidinium parvum
Palaeoperidinium parvum (Harland, 1973) Lentin and Williams, 1976
Originally Lejeunia (an illegitimate generic name), subsequently (and now) Palaeoperidinium.
Holotype: Harland, 1973, pl.84, fig.14
Locus typicus: Southern Alberta, Canada
Stratum typicum: Late Campanian
Original diagnosis: Harland, 1973, p. 672: Lejeunia parva
Proximate cyst, elongate to rhomboidal, made up of autophragm. Test granulate. Epitract elongated into an apical horn which is distally oblate or indented. Hypotract carries two antapical horns, one of which larger than the other both distally acuminate. Cingulum, delimited by raised sutures, is planar to a sightly laevorotatory helicoid. Tabulation ?4", 1a, ?7", 4-?""", 2"""".
Archeopyle not observed.
Dimensions:
Holotype: Length 45.0 µm; breadth 30.0 µm. Range: Length 34.0 (44.4) 57.0 µm; breadth 25.0 (35.5) 41.0 µm. Twenty specimens measured, the number of specimens studied.
Original description: Harland, 1973, p. 673: Lejeunia parva
Apical horn has a thickened structure which may or may not be solid, but invariably shows a suture apparently bisecting the horn. The antapical horns may be well developed or one may appear as a swelling. The tabulation variously developed and where present is delimited by raised sutures. One specimen seen with a complete tabulation. The cingulum, usually conspicuous and approximately three microns wide, may contain granular elements that appear aligned parallel to the longitudinal axis of the cyst. Plate 3" of the tabulation large and conspicuous. Range of variation within this species is not great. The specimen with the tabulation not typical for this species and so not chosen as the holotype.
Affinities:
Harland, 1973, p. 673: Lejeunia parva
This species is similar to that of L. tenella Morgenroth 1966. His specimens, however, lack all trace of tabulation and are larger and more rhomboidal in shape. It is also similar to Palaeoperidinium cretaceum Pocock but differs in being smaller and in not having an endoblast. It has possible peridiniacean affinities.
Originally Lejeunia (an illegitimate generic name), subsequently (and now) Palaeoperidinium.
Holotype: Harland, 1973, pl.84, fig.14
Locus typicus: Southern Alberta, Canada
Stratum typicum: Late Campanian
Original diagnosis: Harland, 1973, p. 672: Lejeunia parva
Proximate cyst, elongate to rhomboidal, made up of autophragm. Test granulate. Epitract elongated into an apical horn which is distally oblate or indented. Hypotract carries two antapical horns, one of which larger than the other both distally acuminate. Cingulum, delimited by raised sutures, is planar to a sightly laevorotatory helicoid. Tabulation ?4", 1a, ?7", 4-?""", 2"""".
Archeopyle not observed.
Dimensions:
Holotype: Length 45.0 µm; breadth 30.0 µm. Range: Length 34.0 (44.4) 57.0 µm; breadth 25.0 (35.5) 41.0 µm. Twenty specimens measured, the number of specimens studied.
Original description: Harland, 1973, p. 673: Lejeunia parva
Apical horn has a thickened structure which may or may not be solid, but invariably shows a suture apparently bisecting the horn. The antapical horns may be well developed or one may appear as a swelling. The tabulation variously developed and where present is delimited by raised sutures. One specimen seen with a complete tabulation. The cingulum, usually conspicuous and approximately three microns wide, may contain granular elements that appear aligned parallel to the longitudinal axis of the cyst. Plate 3" of the tabulation large and conspicuous. Range of variation within this species is not great. The specimen with the tabulation not typical for this species and so not chosen as the holotype.
Affinities:
Harland, 1973, p. 673: Lejeunia parva
This species is similar to that of L. tenella Morgenroth 1966. His specimens, however, lack all trace of tabulation and are larger and more rhomboidal in shape. It is also similar to Palaeoperidinium cretaceum Pocock but differs in being smaller and in not having an endoblast. It has possible peridiniacean affinities.