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Gerdiocysta conopeum
Gerdiocysta conopeum Liengjarern et al., 1980
Holotype: Liengjarern et al., 1980, pl.53, fig.2
Locus typicus: Bouldnor Cliff, Isle of Wight, S England
Stratum typicum: Early Oligocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Gerdiocysta conopeum Liengjarern et al., 1980, has a finely reticulate to membranous, perforate, simulate ectophragm developed over most of the plates. An arcuate to soleate complex of reduced processes, distally free, may be developed on paraplate 6". Low ridges, sometimes forming a reticulum, connect the processes proximally. Size: length of central body (without operculum) 47-64 µm, width 63-79 µm, process length 6-23 µm.
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Original diagnosis: Liengjarern et al., 1980, p.483
Gerdiocysta characterized by a finely reticulate to membranous perforate simulate ectophragm developed over paraplates 1'-4', 1"-5", 2'''-4''', 1p.v., 1''''; an arcuate to soleate complex of very reduced processes, distally free, may be developed on paraplate 6". The process bases are connected by microgranular thickenings of the cyst wall which form low ridges within the complexes; these thickenings are often further developed into an intratabular irregular, coarse reticulum. Individual processes are solid, slightly fibrous, and distally furcated. The median ventral area is large.
Original description: Liengjarern et al., 1980, p.483
The antapical bilobation of the central body may be moderately or only weakly marked. The dorsal convexity and ventral depression are moderate. The endophragm is finely granulose, apparently perforate. The periphragm, as seen on the process walls is slightly fibrous.
The process complexes are determined proximally by basal granulose thickenings on the cyst wall, which form a more or less continuous basal ridge. Distally, the simulate ectophragm is well developed over paraplates 1'-4', 1"-5", 2'''-4''', 1p.v., and 1''''. The cingular paraplates 2c-4c may bear linear complexes of processes which may or may not be distally united. A narrow ectophragm may also be developed on the ventral surface, forming an arcuate wing bordering the central area free of ornament. The ectophragm is closely perforate and finely reticulate or membranous; both types may combine in the same species.
On some individuals, the processes are greatly reduced, no ectophragm is developed, but a coarse granulate basal reticulum extends over the dorsal plate surfaces; intermediate forms between these and normal specimens with well-developed processes and ectophragm are common.
Size: Holotype: length of central body (without operculum) 64 µm, breadth of central body 73 µm, height of processes up to 20 µm. Range of 15 specimens: length of central body (without operculum) 47(55)64 µm, breadth of central body 63(68)79 µm, length of processes 6-23 µm.
Holotype: Liengjarern et al., 1980, pl.53, fig.2
Locus typicus: Bouldnor Cliff, Isle of Wight, S England
Stratum typicum: Early Oligocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Gerdiocysta conopeum Liengjarern et al., 1980, has a finely reticulate to membranous, perforate, simulate ectophragm developed over most of the plates. An arcuate to soleate complex of reduced processes, distally free, may be developed on paraplate 6". Low ridges, sometimes forming a reticulum, connect the processes proximally. Size: length of central body (without operculum) 47-64 µm, width 63-79 µm, process length 6-23 µm.
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Original diagnosis: Liengjarern et al., 1980, p.483
Gerdiocysta characterized by a finely reticulate to membranous perforate simulate ectophragm developed over paraplates 1'-4', 1"-5", 2'''-4''', 1p.v., 1''''; an arcuate to soleate complex of very reduced processes, distally free, may be developed on paraplate 6". The process bases are connected by microgranular thickenings of the cyst wall which form low ridges within the complexes; these thickenings are often further developed into an intratabular irregular, coarse reticulum. Individual processes are solid, slightly fibrous, and distally furcated. The median ventral area is large.
Original description: Liengjarern et al., 1980, p.483
The antapical bilobation of the central body may be moderately or only weakly marked. The dorsal convexity and ventral depression are moderate. The endophragm is finely granulose, apparently perforate. The periphragm, as seen on the process walls is slightly fibrous.
The process complexes are determined proximally by basal granulose thickenings on the cyst wall, which form a more or less continuous basal ridge. Distally, the simulate ectophragm is well developed over paraplates 1'-4', 1"-5", 2'''-4''', 1p.v., and 1''''. The cingular paraplates 2c-4c may bear linear complexes of processes which may or may not be distally united. A narrow ectophragm may also be developed on the ventral surface, forming an arcuate wing bordering the central area free of ornament. The ectophragm is closely perforate and finely reticulate or membranous; both types may combine in the same species.
On some individuals, the processes are greatly reduced, no ectophragm is developed, but a coarse granulate basal reticulum extends over the dorsal plate surfaces; intermediate forms between these and normal specimens with well-developed processes and ectophragm are common.
Size: Holotype: length of central body (without operculum) 64 µm, breadth of central body 73 µm, height of processes up to 20 µm. Range of 15 specimens: length of central body (without operculum) 47(55)64 µm, breadth of central body 63(68)79 µm, length of processes 6-23 µm.