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Palaeohystrichophora pikeae
Palaeohystrichophora "pikeae" Churchill and Sarjeant, 1962, p.40–41, figs.6,24.
NOW Cobricosphaeridium (acritarch genus). Originally Palaeohystrichophora, subsequently Aquadulcum (acritarch genus), thirdly (and now) Cobricosphaeridium (acritarch genus).
Holotype: Churchill and Sarjeant, 1962, figs.6,24.
Age: Holocene.
Original diagnosis: Churchill and Sarjeant, 1962, p.40
A species of Palaeohystrichophora having an ovoidal shell, with epitheca rounded conical, larger than the hypotheca, and hypotheca hemispherical. Transverse furrow narrow, laevo-rotatory; longitudinal furrow narrow, extending from apex to antapex. The shell surface, except for the furrows, bears a dense cover of short spines bifurcating at a constant distance from the shell surface.
Original description: Churchill and Sarjeant, 1962, p.40
Shell pale yellowish-brown not, or only very minutely, granular. The hvo ends of the transverse furrow, which is slightly "hollowed", differ in anterior-posterior position by twice the furrow"s width. The longitudinal furrow is not hollowed and is recognizable only through its lack of spines.
Dimensions:
overall length 35 µm, breadth 32 µm, shell length 32.5 µm, breadth 29.5 µm, spines ca. 2 µm long.
Observed range: length of shell 33--37 µm (14 specimens).
Affinities:
Churchill and Sarjeant, 1962, p.40-41: Palaeohystrichophora pikei differs from all described species in its shape, the character of its furrows, and the nature of its spine cover. The two most comparable described species are Palaeohystrichophora multispina Deflandre and Cookson 1955 and P. dispersa Cookson and Eisenack 1958, respectively from the Upper and Lower Cretaceous of Western Australia. However, both species differ from P. pikei in their fusiform shape; P. multispina has a truncate apical process and entirely simple spines and P. dispersa has processes at both apex and antapex and has truncate, not bifurcate, spines. Palaeohystrichophora pikeae.
NOW Cobricosphaeridium (acritarch genus). Originally Palaeohystrichophora, subsequently Aquadulcum (acritarch genus), thirdly (and now) Cobricosphaeridium (acritarch genus).
Holotype: Churchill and Sarjeant, 1962, figs.6,24.
Age: Holocene.
Original diagnosis: Churchill and Sarjeant, 1962, p.40
A species of Palaeohystrichophora having an ovoidal shell, with epitheca rounded conical, larger than the hypotheca, and hypotheca hemispherical. Transverse furrow narrow, laevo-rotatory; longitudinal furrow narrow, extending from apex to antapex. The shell surface, except for the furrows, bears a dense cover of short spines bifurcating at a constant distance from the shell surface.
Original description: Churchill and Sarjeant, 1962, p.40
Shell pale yellowish-brown not, or only very minutely, granular. The hvo ends of the transverse furrow, which is slightly "hollowed", differ in anterior-posterior position by twice the furrow"s width. The longitudinal furrow is not hollowed and is recognizable only through its lack of spines.
Dimensions:
overall length 35 µm, breadth 32 µm, shell length 32.5 µm, breadth 29.5 µm, spines ca. 2 µm long.
Observed range: length of shell 33--37 µm (14 specimens).
Affinities:
Churchill and Sarjeant, 1962, p.40-41: Palaeohystrichophora pikei differs from all described species in its shape, the character of its furrows, and the nature of its spine cover. The two most comparable described species are Palaeohystrichophora multispina Deflandre and Cookson 1955 and P. dispersa Cookson and Eisenack 1958, respectively from the Upper and Lower Cretaceous of Western Australia. However, both species differ from P. pikei in their fusiform shape; P. multispina has a truncate apical process and entirely simple spines and P. dispersa has processes at both apex and antapex and has truncate, not bifurcate, spines. Palaeohystrichophora pikeae.