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Glaphyrocysta retiintexta
Glaphyrocysta retiintexta (Cookson, 1965) Stover and Evitt, 1978
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Cookson, 1965a, pl.11, fig.4; Eisenack and Kjellström, 1972, p.325; Fensome et al., 1996, fig.1 — p.2329.
Locus typicus: Frome Broken Hill Co. Eumeralla No. 1 Bore, cuttings taken between 3090 and 3100 ft, and 3110 and 3120 ft, SW Australia
Stratum typicum: ?Senonian
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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.
Glaphyrocysta retiintexta (Cookson, 1965a) Stover and Evitt, 1978, has an open-meshed network, formed by the distal anastomosing of simple or, more commonly, slender branched processes of variable widths (ca 0.5-5 µm), which arise on the ambitus and also extend well onto the middorsal and midventral surface of the body. The distal trabeculae may be flattened and perforated. This species differs from Glaphyrocysta reticulosa in having a smaller area devoid of processes. Overall size: Holotype: length 177 µm, width 117 µm.
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Original description: Cookson, 1965, p.88: Cyclonephelium retiintextum
Shell oval with a small, median, blunt apical projection; archeopyle apical. Ornament in the form of an open-meshed network formed by the distal anastomosis of simple or more commonly slender branched processes of variable widths (c. 0.5-5 µm) which arise well within the margin of the shell (c. 15-21 µm); sometimes the bases of adjacent processes are connected by straight or curved strands. The distal branches delimiting the meshes are occasionally somewhat flattened and slightly perforated. The unornamented central portions of both dorsal and ventral surfaces are relatively small (c. 42 µm wide in the holotype). The shell membrane is two-layered, thin (c. 1 µm) and finely granular.
Dimensions: Holotype overall length 177 µm, overall width 117 µm, shell 94x78 µm, appendages 20-30 µm long.
Affinities:
Cookson, 1965, p.88: Cyclonephelium retiintextum
Of the described species of Cyclonephelium the one to which C. retiintextum approaches at all closely is C. reticulosum Gerlach (1961) from an Upper Oligocene deposit in NW. Germany. In this species, it is evident from the description and figure that the processes forming the network are situated close to the margin of the shell and that, in consequence, the greater part of both dorsal and ventral surfaces are unornamented. This arrangement clearly contrasts with the more central position of the network and the consequent smaller size of the unornamented surfaces of C. retiintextum. In addition, the distal finely reticulate bands associated with the reticulum of C. reticulosum have not been observed in C. retiintextum.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Cookson, 1965a, pl.11, fig.4; Eisenack and Kjellström, 1972, p.325; Fensome et al., 1996, fig.1 — p.2329.
Locus typicus: Frome Broken Hill Co. Eumeralla No. 1 Bore, cuttings taken between 3090 and 3100 ft, and 3110 and 3120 ft, SW Australia
Stratum typicum: ?Senonian
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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.
Glaphyrocysta retiintexta (Cookson, 1965a) Stover and Evitt, 1978, has an open-meshed network, formed by the distal anastomosing of simple or, more commonly, slender branched processes of variable widths (ca 0.5-5 µm), which arise on the ambitus and also extend well onto the middorsal and midventral surface of the body. The distal trabeculae may be flattened and perforated. This species differs from Glaphyrocysta reticulosa in having a smaller area devoid of processes. Overall size: Holotype: length 177 µm, width 117 µm.
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Original description: Cookson, 1965, p.88: Cyclonephelium retiintextum
Shell oval with a small, median, blunt apical projection; archeopyle apical. Ornament in the form of an open-meshed network formed by the distal anastomosis of simple or more commonly slender branched processes of variable widths (c. 0.5-5 µm) which arise well within the margin of the shell (c. 15-21 µm); sometimes the bases of adjacent processes are connected by straight or curved strands. The distal branches delimiting the meshes are occasionally somewhat flattened and slightly perforated. The unornamented central portions of both dorsal and ventral surfaces are relatively small (c. 42 µm wide in the holotype). The shell membrane is two-layered, thin (c. 1 µm) and finely granular.
Dimensions: Holotype overall length 177 µm, overall width 117 µm, shell 94x78 µm, appendages 20-30 µm long.
Affinities:
Cookson, 1965, p.88: Cyclonephelium retiintextum
Of the described species of Cyclonephelium the one to which C. retiintextum approaches at all closely is C. reticulosum Gerlach (1961) from an Upper Oligocene deposit in NW. Germany. In this species, it is evident from the description and figure that the processes forming the network are situated close to the margin of the shell and that, in consequence, the greater part of both dorsal and ventral surfaces are unornamented. This arrangement clearly contrasts with the more central position of the network and the consequent smaller size of the unornamented surfaces of C. retiintextum. In addition, the distal finely reticulate bands associated with the reticulum of C. reticulosum have not been observed in C. retiintextum.