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Exochosphaeridium cenomaniense
Exochsphaeridium cenomaniense Norvick in Norvick and Burger, 1976
Now Pervosphaeridium. Originally Exochosphaeridium, subsequently Exochosphaeridium?, thirdly (and now) Pervosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Exochosphaeridium.
Holotypus: Norvick, 1976, pl.4, fig.4
Locus typicus: Bathurst Island no. 1 well, Australia
Stratum typicum: Cenomanian
Original diagnosis: Norvick, 1976, p.52-53
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
Chorate cyst with a spherical to prolate central body and medium to long tapering processes. The processes reach 18 Ám in length, with a solid or fibrous structure and pointed or minutely capitate distal extremities. The process bases are up to 5 Ám 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 Ám to 1 Ám thick and lumina up to 1 Ám 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 Ámthick.
Dimensions: Overall diameter ranges between 51 and 97 Ám (average 74 Ám for 24 specimens).
Now Pervosphaeridium. Originally Exochosphaeridium, subsequently Exochosphaeridium?, thirdly (and now) Pervosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Exochosphaeridium.
Holotypus: Norvick, 1976, pl.4, fig.4
Locus typicus: Bathurst Island no. 1 well, Australia
Stratum typicum: Cenomanian
Original diagnosis: Norvick, 1976, p.52-53
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
Chorate cyst with a spherical to prolate central body and medium to long tapering processes. The processes reach 18 Ám in length, with a solid or fibrous structure and pointed or minutely capitate distal extremities. The process bases are up to 5 Ám 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 Ám to 1 Ám thick and lumina up to 1 Ám 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 Ámthick.
Dimensions: Overall diameter ranges between 51 and 97 Ám (average 74 Ám for 24 specimens).