Back
Systematophora ovata
Systematophora? ovata Gitmez and Sarjeant, 1972
Originally (and now) Systematophora, subsequently Systematophora?, thirdly Egmontodinium. Stover and Evitt, 1978 considered this to be a provisionally accepted species of Systematophora. Riley, 1979 transferred this species to
Egmontodinium Gitmez and Sarjeant, 1972; however, Courtinat, 1989 retained the species in Systematophora without question.
Holotype: Gitmez and Sarjeant, 1972, pl.14, fig.2-3
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Stretham, Cambridgeshire, England
Stratum typicum: Lower Kimmeridgian
Translation Courtinat, 1989: LPP
Original diagnosis: Gitmez and Sarjeant, 1972, p.237
A species of Systematophora having an elongate, ovoidal cyst bearing short processors (not more than one-fourth of the cyst breadth). The processes are located in groups: there are ten such groups, one occupying the apex, an opposite one the antapex, whilst eight groups are distributed between the apex and the antapex, four of them on the epitract, the other four on the hypotract. There is no connection between the groups of processes or between the processes in each group. The processes are simple, bifid distal or broad based, foliate and deeply forked at their distal end. The surface of the shell is finely granular. When an archaeoyle is developed, it is apical in position.
Dimensions: Holotype: shell length (apex lacking) 35 µm, breadth 28 µm, process length 6-8 µm. Paratype: shell length 58 µm, breadth 40 µm, process length 8 µm. Range: shell length 58-60 µm, apex lacking 35-48 µm, breadth 2 µm, process length 8-11 µm. Measured specimens were 6 in number.
Original description: Gitmez and Sarjeant, 1972, p.237
The cyst wall is composed of two layers, the periphragm forming the processes. Both of the layers are thin and transparent. There is no connection between the processes at their proximal and distal ends; they arise separately from each other, positioned around the margins of ovoidal or polygonal fields whose shape is clearly shown by the broad bases of the processes.
Courtinat, 1989, p.173
Remark: The new combination (Egmontodinium ovatum) proposed by Riley (1979) and accepted by Lentin and Williams (1985) is not retained because the nature of the processes, their arrangement in annular complexes, the absence of trabeculae of any kind are characteristics exclusive to the genus Systematophora, whilst in Egmontodinium there are no annular complexes. The paraplates are indicated by thick crests. S. ovata possesses very short processes, attached to very high crests which form annular complexes; no connection by trabeculae is observed.
Originally (and now) Systematophora, subsequently Systematophora?, thirdly Egmontodinium. Stover and Evitt, 1978 considered this to be a provisionally accepted species of Systematophora. Riley, 1979 transferred this species to
Egmontodinium Gitmez and Sarjeant, 1972; however, Courtinat, 1989 retained the species in Systematophora without question.
Holotype: Gitmez and Sarjeant, 1972, pl.14, fig.2-3
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Stretham, Cambridgeshire, England
Stratum typicum: Lower Kimmeridgian
Translation Courtinat, 1989: LPP
Original diagnosis: Gitmez and Sarjeant, 1972, p.237
A species of Systematophora having an elongate, ovoidal cyst bearing short processors (not more than one-fourth of the cyst breadth). The processes are located in groups: there are ten such groups, one occupying the apex, an opposite one the antapex, whilst eight groups are distributed between the apex and the antapex, four of them on the epitract, the other four on the hypotract. There is no connection between the groups of processes or between the processes in each group. The processes are simple, bifid distal or broad based, foliate and deeply forked at their distal end. The surface of the shell is finely granular. When an archaeoyle is developed, it is apical in position.
Dimensions: Holotype: shell length (apex lacking) 35 µm, breadth 28 µm, process length 6-8 µm. Paratype: shell length 58 µm, breadth 40 µm, process length 8 µm. Range: shell length 58-60 µm, apex lacking 35-48 µm, breadth 2 µm, process length 8-11 µm. Measured specimens were 6 in number.
Original description: Gitmez and Sarjeant, 1972, p.237
The cyst wall is composed of two layers, the periphragm forming the processes. Both of the layers are thin and transparent. There is no connection between the processes at their proximal and distal ends; they arise separately from each other, positioned around the margins of ovoidal or polygonal fields whose shape is clearly shown by the broad bases of the processes.
Courtinat, 1989, p.173
Remark: The new combination (Egmontodinium ovatum) proposed by Riley (1979) and accepted by Lentin and Williams (1985) is not retained because the nature of the processes, their arrangement in annular complexes, the absence of trabeculae of any kind are characteristics exclusive to the genus Systematophora, whilst in Egmontodinium there are no annular complexes. The paraplates are indicated by thick crests. S. ovata possesses very short processes, attached to very high crests which form annular complexes; no connection by trabeculae is observed.