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Achomosphaera cf. neptunii sensu davey and verdier 1974
Achomosphaera neptuni sensu Davey and Verdier, 1974
Description (Davey & Verdier, 1974)
This ovoidal cyst has a smooth to minutely granular, thin wall which bears many smooth to slightly fibrous processes. Each process has a wide flat base and tapers rapidly to become thin and parallel-sided. Towards the distal extremity they divide into two, rarely three, filamentous branches which occasionally can be seen to further bifurcate at their distal extremities. Some alignment of the processes is present and appears to mark the cingular margins; a short, stouter apical process is sometimes discernible. These two features allow cyst orientation which suggests that the archaeopyle is precingular in position. It is formed by the loss of a single plate and is roughly triangular in shape. The processes are apparently both gonal and sutural in position.
Dimensions. Central body diameter of figured specimen (µm) 44x51, range 41-51
Length of processes of figured specimen (µm) 7-15, range 7-15
Remarks. A. neptuni differs from A. cf. neptuni by being thicker walled with a coarser granulation and by having fewer and wider processes which often join proximally with neighbouring processes. The processes of A. neptuni appear to be only gonal and usually trifurcate distally to give thick spines.
Description (Davey & Verdier, 1974)
This ovoidal cyst has a smooth to minutely granular, thin wall which bears many smooth to slightly fibrous processes. Each process has a wide flat base and tapers rapidly to become thin and parallel-sided. Towards the distal extremity they divide into two, rarely three, filamentous branches which occasionally can be seen to further bifurcate at their distal extremities. Some alignment of the processes is present and appears to mark the cingular margins; a short, stouter apical process is sometimes discernible. These two features allow cyst orientation which suggests that the archaeopyle is precingular in position. It is formed by the loss of a single plate and is roughly triangular in shape. The processes are apparently both gonal and sutural in position.
Dimensions. Central body diameter of figured specimen (µm) 44x51, range 41-51
Length of processes of figured specimen (µm) 7-15, range 7-15
Remarks. A. neptuni differs from A. cf. neptuni by being thicker walled with a coarser granulation and by having fewer and wider processes which often join proximally with neighbouring processes. The processes of A. neptuni appear to be only gonal and usually trifurcate distally to give thick spines.