Back
Palaeohystrichophora granulata
Palaeohystrichophora granulata Mao Shaozhi and Norris, 1988
Holotype: Mao Shaozhi and Norris, 1988, pl.12, fig.11
Locus typicus: Kukebai Formation, Wuluokeqiate section, China
Stratum typicum: Late Cretaceous
Original diagnosis: Mao Shaozhi and Norris, 1988, p. 47
Cyst proximate, typically bicavate, with distinct apical horn and two unequally or weakly developed antapical horns. Wall thin; periphragm finely granulate, bearing a
few sporadically distributed hairlike processes; endophragm smooth to sparsely granulate. Endoblast subspherical to rhombic, width equal to or typically slightly
greater than length. Cingulum always present, bounded by folds or low ridges. Archeopyle usually indiscernible; if indicated, combination of intercalary and precingular, type (313P). Operculum attached posteriorly like a flap.
Original description: Mao Shaozhi and Norris, 1988, p. 47
Cyst compressed peridinioid, rounded pentagonal. Tapering apical horn triangular in shape, 7 to 12.5 µm high, base broader than height. Two antapical horns either
weakly and equally developed as a pair of bulges (3 to 4 µm high) or unequally developed, left one being high (5 to 10 µm) and more pointed than right. Two-layered wall less than 1 µm thick; periphragm transparent, not accepting stain readily, finely granulate, typically bearing several (usually less than 10) sporadic hairlike spines.
Subspherical endoblast protruding more into epitract than hypotract, with breadth (44 to 54 µm) slightly greater than length (40 to 50 mm), occupying most of pericoel, leaving small apical and antapical pericoels and very narrow (1 to 3 µm) ambital pericoel.
Cingulum well defined, planar, 4 to 6 µm wide.
Most of observed specimens showing no indication of archeopyle. Rarely, simple flap-like operculum remaining attached posteriorly, indicating archeopyle probably composed of three intercalary and three precingular plates (1 to 3a, 3 to 5").
Dimensions: Length 58 to 70 µm (holotype 64 µm), width 44 to 56 µm (holotype 55 µm).
Affinities:
Mao Shaozhi and Norris, 1988, p. 47: The present new species shows similarity to Palaeohystrichophora infusorioides but differs in having granules and only a few sporadic hairlike processes on its periphragm, whereas the latter bears numerous and evenly distributed hairlike processes. P. granulata differs from Talimudinium scissurum sp. nov. in possessing the following combination of features: ( I ) the periphragm usually bears a few sporadic hairlike processes; (2) the width of the
endoblast is equal to or, typically, slightly greater than the length of it; (3) the archeopyle is a combination of (313P) rather than a combination of (A312P).
Holotype: Mao Shaozhi and Norris, 1988, pl.12, fig.11
Locus typicus: Kukebai Formation, Wuluokeqiate section, China
Stratum typicum: Late Cretaceous
Original diagnosis: Mao Shaozhi and Norris, 1988, p. 47
Cyst proximate, typically bicavate, with distinct apical horn and two unequally or weakly developed antapical horns. Wall thin; periphragm finely granulate, bearing a
few sporadically distributed hairlike processes; endophragm smooth to sparsely granulate. Endoblast subspherical to rhombic, width equal to or typically slightly
greater than length. Cingulum always present, bounded by folds or low ridges. Archeopyle usually indiscernible; if indicated, combination of intercalary and precingular, type (313P). Operculum attached posteriorly like a flap.
Original description: Mao Shaozhi and Norris, 1988, p. 47
Cyst compressed peridinioid, rounded pentagonal. Tapering apical horn triangular in shape, 7 to 12.5 µm high, base broader than height. Two antapical horns either
weakly and equally developed as a pair of bulges (3 to 4 µm high) or unequally developed, left one being high (5 to 10 µm) and more pointed than right. Two-layered wall less than 1 µm thick; periphragm transparent, not accepting stain readily, finely granulate, typically bearing several (usually less than 10) sporadic hairlike spines.
Subspherical endoblast protruding more into epitract than hypotract, with breadth (44 to 54 µm) slightly greater than length (40 to 50 mm), occupying most of pericoel, leaving small apical and antapical pericoels and very narrow (1 to 3 µm) ambital pericoel.
Cingulum well defined, planar, 4 to 6 µm wide.
Most of observed specimens showing no indication of archeopyle. Rarely, simple flap-like operculum remaining attached posteriorly, indicating archeopyle probably composed of three intercalary and three precingular plates (1 to 3a, 3 to 5").
Dimensions: Length 58 to 70 µm (holotype 64 µm), width 44 to 56 µm (holotype 55 µm).
Affinities:
Mao Shaozhi and Norris, 1988, p. 47: The present new species shows similarity to Palaeohystrichophora infusorioides but differs in having granules and only a few sporadic hairlike processes on its periphragm, whereas the latter bears numerous and evenly distributed hairlike processes. P. granulata differs from Talimudinium scissurum sp. nov. in possessing the following combination of features: ( I ) the periphragm usually bears a few sporadic hairlike processes; (2) the width of the
endoblast is equal to or, typically, slightly greater than the length of it; (3) the archeopyle is a combination of (313P) rather than a combination of (A312P).