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Fibrocysta ovalis
Fibrocysta ovalis (Hansen, 1977) Lentin and Williams, 1981
Originally Lanternosphaeridium, subsequently (and now) Fibrocysta
Holotype: Hansen, 1977, figs.19F,G
Locus typicus: Tuba 13 well, Copenhagen, Denmark
Stratum typicum: Maastrichtian-Danian
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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.
Fibrocysta ovalis (Hansen, 1977) Lentin and Williams, 1981. According to Hansen (1977), has an oval central body and variable number of similar processes. The periphragm is finely fibrous. Processes intratabular, solid, circular in cross-section and formed by numerous, hardly visible, coalescent fibres. More than one process per plate. There is a tendency to a circular arrangement of the processes in the cingular region. Size: diameter of central body 70-86 µm, overall diameter 120-126 µm, thickness of wall 4 µm.
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Original diagnosis: Hansen, 1977, p. 17
Lanternosphaeridium Morgenroth, 1967 with an oval central body and with a variable number of similar processes.
Description: Hansen, 1977, p. 17
The oval central body consists of an inner, seemingly structureless layer (endophragm) and an outer very finely fibrous layer (periphragm). Processes intratabular, solid, circular in cross-section and formed by numerous hardly visible coalescent fibres. More than one process per plate area. There is a tendency to a circular arrangement of the processes in the cingular region. Archaeopyle type P. Operculum becomes typically completely detached.
Supplemental description: Hultberg, 1985, p. 124
Chorate cyst, composed of endophragm and periphragm, appressed between processes. The surface of the endophragm is smooth. The surface of the periphragm is slightly fibrous. The shape of the cyst is ellipsoidal. No trace of paratabulation is present, except archeopyle. The ornamentation consists of nontabular processes. The processes are solid, slightly fibrous, and bifurcate. Some processes, mostly in the paracingular area are joined in pairs. Occasional processes may have multifurcate to digitate process-tips. The archeopyle is precingular, type P, formed by the detachment of paraplate 3''. Operculum free.
Size 110-124 Ám (diameter).
Affinities:
Hultberg, 1985, p. 124: Fibrocysta ovalis is clearly distinguishable from F. axialis
by the absence of an apical protrusion.
Originally Lanternosphaeridium, subsequently (and now) Fibrocysta
Holotype: Hansen, 1977, figs.19F,G
Locus typicus: Tuba 13 well, Copenhagen, Denmark
Stratum typicum: Maastrichtian-Danian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Fibrocysta ovalis (Hansen, 1977) Lentin and Williams, 1981. According to Hansen (1977), has an oval central body and variable number of similar processes. The periphragm is finely fibrous. Processes intratabular, solid, circular in cross-section and formed by numerous, hardly visible, coalescent fibres. More than one process per plate. There is a tendency to a circular arrangement of the processes in the cingular region. Size: diameter of central body 70-86 µm, overall diameter 120-126 µm, thickness of wall 4 µm.
--------------------------------------------------
Original diagnosis: Hansen, 1977, p. 17
Lanternosphaeridium Morgenroth, 1967 with an oval central body and with a variable number of similar processes.
Description: Hansen, 1977, p. 17
The oval central body consists of an inner, seemingly structureless layer (endophragm) and an outer very finely fibrous layer (periphragm). Processes intratabular, solid, circular in cross-section and formed by numerous hardly visible coalescent fibres. More than one process per plate area. There is a tendency to a circular arrangement of the processes in the cingular region. Archaeopyle type P. Operculum becomes typically completely detached.
Supplemental description: Hultberg, 1985, p. 124
Chorate cyst, composed of endophragm and periphragm, appressed between processes. The surface of the endophragm is smooth. The surface of the periphragm is slightly fibrous. The shape of the cyst is ellipsoidal. No trace of paratabulation is present, except archeopyle. The ornamentation consists of nontabular processes. The processes are solid, slightly fibrous, and bifurcate. Some processes, mostly in the paracingular area are joined in pairs. Occasional processes may have multifurcate to digitate process-tips. The archeopyle is precingular, type P, formed by the detachment of paraplate 3''. Operculum free.
Size 110-124 Ám (diameter).
Affinities:
Hultberg, 1985, p. 124: Fibrocysta ovalis is clearly distinguishable from F. axialis
by the absence of an apical protrusion.