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Perisseiasphaeridium insolitum
Perisseiasphaeridium insolitum Davey, 1982
Holotype: Davey, 1982, pl. 4, figs. 8-10
Locus typicus: Haldager No.1 Borehole, Denmark
Stratum typicum: Early Portlandium-early Ryazanian
Original diagnosis: Davey, 1982, p. 19
Shape: The body is subspherical in shape.
Wall: The two wall layers are closely appressed except where the periphragm forms the processes. The surface is more or less smooth.
Processes: The plate-centered, tubiform processes are arranged 4", 6", 5""", Ip, 1"""", Ips: they flare distal y to give rise to several aculeate spines. There are six pairs of solid, paracingular processes and up to four additional parasulcal processes; these processes typically bifurcate distally. The 1""" process, when present, is of the latter type.
Archaeopyle: An apical archaeopyle (Type A) is typically developed.
Original description: Davey, 1982, p. 19
The cyst wall is thin, being under 1 µm in thickness, and is consequential often distorted andior broken. The solid and tubiform processes are of comparable length and approximately equal to half the body diameter. The tubiform processes are sometimes faintly striate along their lengths and proximally adjacent to the cyst body: the stem width varies from 3 to 6 µm. The solid processes measure less than 2 µm in thickness. The paracingular region appears usually to possess aligned, low, ovoidal ridges one per paraplate with each process of the paracingular pair arising from one end of the ridge.
Holotype: Davey, 1982, pl. 4, figs. 8-10
Locus typicus: Haldager No.1 Borehole, Denmark
Stratum typicum: Early Portlandium-early Ryazanian
Original diagnosis: Davey, 1982, p. 19
Shape: The body is subspherical in shape.
Wall: The two wall layers are closely appressed except where the periphragm forms the processes. The surface is more or less smooth.
Processes: The plate-centered, tubiform processes are arranged 4", 6", 5""", Ip, 1"""", Ips: they flare distal y to give rise to several aculeate spines. There are six pairs of solid, paracingular processes and up to four additional parasulcal processes; these processes typically bifurcate distally. The 1""" process, when present, is of the latter type.
Archaeopyle: An apical archaeopyle (Type A) is typically developed.
Original description: Davey, 1982, p. 19
The cyst wall is thin, being under 1 µm in thickness, and is consequential often distorted andior broken. The solid and tubiform processes are of comparable length and approximately equal to half the body diameter. The tubiform processes are sometimes faintly striate along their lengths and proximally adjacent to the cyst body: the stem width varies from 3 to 6 µm. The solid processes measure less than 2 µm in thickness. The paracingular region appears usually to possess aligned, low, ovoidal ridges one per paraplate with each process of the paracingular pair arising from one end of the ridge.