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Glaphyrocysta marlboroughensis

Glaphyrocysta marlboroughensis Schiøler and Wilson, 1998, Plate 5, figs. 1-6

Holotype: Schiøler and Wilson, 1998, Plate 5, Fig. 5
Paratypes: Schiøler and Wilson, 1998, Plate 5, Fig. 1, 2, 3
Repository: The palynological type collection, Institute of Geological and Nuclear Sciences, Lower Hutt, New Zealand.
Type locality: Ben More section, south Marlborough, New Zealand.
Type stratum: Herring Formation at 168.7 m on log P30c6. Upper Piripauan (middle to upper Santonian).
Derivation of name: After the Marlborough region, South Island, New Zealand.

Diagnosis: Lenticular marginate autocyst with a rounded apex and antapex. Autophragm granulate. Solid processes rise from margins of phragm. Processes joined proximally in linear to arcuate groups and have bifurcate to multifurcate terminations usually connected distally by trabeculae in process groups; trabeculae often are serrate to finely denticulate. Processes near archeopyle margin are short, less than half length of antapical processes. The larger antapical processes usually have fenestrate terminations. Archeopyle apical, type tA, and free.

Description: Lenticular marginate autocyst with round apex and antapex. The phragm of the cyst body is thin and granulate (phragm thickness: <0.5 µm). Solid processes arise from the margins of the cyst; most of the ventral and dorsal areas are devoid of processes. The process length decreases from the antapical margin towards the archeopyle margin (length of antapical processes c 30 µm, length of ad-cingular processes c 15µm). The processes have narrow solid stems and are joined proximally in linear to arcuate complexes. The process terminations are bifurcate to multifurcate. The tips of some of the processes in a process complex merge distally to form trabeculae. The outer edge of the trabeculae may be serrate to finely denticulate. The paracingulum is often indicated by an increased height of processes in the equatorial area (Plate 5, figs. 2-3). The parasulcus is indicated by a notch in the archeopyle margin. The archeopyle is apical, type tA, the operculum is free. The paratabulation is not indicated or indicated inconsistently by process complexes.

Dimensions (in µm):
holotyperange
Length of cyst body (without operculum) 78 63 (86) 98
Width of cyst body 101 77 (101) 113
Total length(without operculum)114 89 (116) 134
Total width134 119 (140) 149
Number of specimens measured: 10

Stratigraphic occurrence: 168.7-238.5 m in the Ben More section, 247-271 m in the Kekerengu section. Upper Piripauan-Haumurian (Santonian, Upper Cretaceous) in the Herring Formation, south Marlborough, New Zealand.

Remarks: Glaphyrocysta marlboroughensis sp. nov. differs from Glaphyrocysta circularis Matsuoka, 1984 in being larger and in lacking a linear process complex on paraplate 3''. It differs further from the latter species in having only partial development of trabeculae in a process complex rather than a regular arrangement of trabeculae connecting all processes in the process complex into circular rings. It differs from Glaphyrocysta dentata Matsuoka, 1984 in having solid rather than tubiform processes. The new species differs from Glaphyrocysta divaricata (Williams and Downie, 1966) Stover and Evitt, 1978, Glaphyrocysta exuberans (Deflandre and Cookson, 1955) Stover and Evitt, 1978, Glaphyrocysta ordinata (Williams and Downie, 1966) Stover and Evitt, 1978 and Glaphyrocysta pastielsii (Deflandre and Cookson, 1955) Stover and Evitt, 1978 in lacking trace of an entire ectophragm connecting the process tips. Furthermore it is larger than G. divaricata, G. exuberans and G. pastielsii. G. marlboroughensis sp. nov. differs from Cyclonephelium dubium (Jain and Millepied, 1975) Sarjeant and Stover, 1978 in having a rounded apex rather than an apical horn, and in having multifurcate to fenestrate processes. It differs from Glaphyrocysta intricata (Eaton, 1971) Stover and Evitt, 1978 in lacking fenestrate process stems and in being larger. It differs from Glaphyrocysta retiintexta (Cookson, 1965) Stover and Evitt, 1978 in having fewer interconnections between processes and process complexes. G. marlboroughensis sp. nov. differs from Systematophora variabilis (Cookson and Eisenack, 1967) Stover and Evitt, 1978 in having the processes restricted to the cyst margin.
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