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Pervosphaeridium cenomaniense
Pervosphaeridium cenomaniense (Norvick in Norvick and Burger, 1976) Below, 1982
Originally Exochosphaeridium, subsequently Exochosphaeridium?, thirdly
(and now) Pervosphaeridium.
Holotypus: Norvick and Burger, 1976, pl.4, fig.4
Locus typicus: Bathurst Island no. 1 well, Australia
Stratum typicum: Cenomanian
Original diagnosis: Norvick, 1976, p.52-53: Exochsphaeridium cenomaniense
Cyst chorate. Central body prolate or spherical. Processes tapering, solid or fibrous, medium to long. Processes are striate proximally, pointed or minutely capitate distally. Periphragm fibrous, coarsely and irregularly reticulate. Process arrangement random, at least three per plate area. Apical process distinct, often foliate. Archaeopyle precingular, composed of either one or two discrete plates.
Description: Norvick, 1976, p.53: Exochsphaeridium cenomaniense
Chorate cyst with a spherical to prolate central body and medium to long tapering processes. The processes reach 18 µm in length, with a solid or fibrous structure and pointed or minutely capitate distal extremities. The process bases are up to 5 µm broad and, where coarsely fibrous, are sometimes perforate proximally. Fibrils radiate over the periphragm from the process bases and anastomose into a coarse and completely irregular periphragmic net-work. Fibrils are 0.5 µm to 1µm thick and lumina up to 1 µm in diameter. The processes are arranged randomly, three or more per plate area. No trace of cingular alignment could be identified, in the population studied., but the apical process is usually longer than the others and it is often distally foliate. The archaeopyle may be formed by the loss of one or two reflected precingular plate areas. The wall is 1-1.5 µm thick.
Dimensions: Overall diameter ranges between 51 and 97 µm (average 74 µm for 24 specimens).
Originally Exochosphaeridium, subsequently Exochosphaeridium?, thirdly
(and now) Pervosphaeridium.
Holotypus: Norvick and Burger, 1976, pl.4, fig.4
Locus typicus: Bathurst Island no. 1 well, Australia
Stratum typicum: Cenomanian
Original diagnosis: Norvick, 1976, p.52-53: Exochsphaeridium cenomaniense
Cyst chorate. Central body prolate or spherical. Processes tapering, solid or fibrous, medium to long. Processes are striate proximally, pointed or minutely capitate distally. Periphragm fibrous, coarsely and irregularly reticulate. Process arrangement random, at least three per plate area. Apical process distinct, often foliate. Archaeopyle precingular, composed of either one or two discrete plates.
Description: Norvick, 1976, p.53: Exochsphaeridium cenomaniense
Chorate cyst with a spherical to prolate central body and medium to long tapering processes. The processes reach 18 µm in length, with a solid or fibrous structure and pointed or minutely capitate distal extremities. The process bases are up to 5 µm broad and, where coarsely fibrous, are sometimes perforate proximally. Fibrils radiate over the periphragm from the process bases and anastomose into a coarse and completely irregular periphragmic net-work. Fibrils are 0.5 µm to 1µm thick and lumina up to 1 µm in diameter. The processes are arranged randomly, three or more per plate area. No trace of cingular alignment could be identified, in the population studied., but the apical process is usually longer than the others and it is often distally foliate. The archaeopyle may be formed by the loss of one or two reflected precingular plate areas. The wall is 1-1.5 µm thick.
Dimensions: Overall diameter ranges between 51 and 97 µm (average 74 µm for 24 specimens).