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Cymososphaeridium benmorense
Cymososphaeridium benmorense Schiøler and Wilson, 1998, Plate 9, figs. 1-7
Holotype: Schiøler and Wilson, 1998, Plate 9, Fig. 3
Paratypes: Schiøler and Wilson, 1998, Plate 9, figs. 1-2, 4, 5
Repository: The palynological type collection, Institute of Geological and Nuclear Sciences, Lower Hutt, New Zealand.
Type locality: Kekerengu section, south Marlborough, New Zealand.
Type stratum: Paton Formation at 180 m on log P30c17. Upper Teratan (Upper Coniacian).
Derivation of name: After the Ben More Stream, south Marlborough, New Zealand.
Diagnosis: Large skolochorate gonyaulacoid cyst carrying 18 solid or extremely thick-walled intraplate processes (loisthocyst: 14, operculum: 4). Paracingular processes absent. Processes branch up to three times and form open flaring to funnel-shaped terminations. Archeopyle apical, type tA, operculum bears four processes, is simple and free. Paratabulation: 4', 6'', ?c, ?s, 6''', 1p, 1''''.
Description: Two-layered skolochorate gonyaulacoid cyst. The wall layers are normally closely appressed and appear as one. The phragm of the cyst body is thin and smooth (phragm thickness: <0.5 µm). Fourteen intraplate processes arise from the loisthocyst. The paracingulum is process-free. Four intraplate processes arise from the operculum (Plate 9, Fig. 6). All processes branch distally one, two and rarely three times and form broad flaring to funnel-shaped terminations. Normally, the branching occurs in the distal fourth to fifth of the process, but in extreme cases the branching may occur half way along the process. The process wall is thick and the processes appear solid; however, on some specimens a small triangular pericoel is developed at the base of some processes, revealing the presence of two wall layers (Plate 9, figs. 1, 4). Likewise, a narrow channel is sometimes visible within the distal half of the process, descending from the process termination and steadily narrowing until the process walls merge and the channel disappears (Plate 9, Fig. 7). The parasulcus is not indicated. The paracingulum is indicated equatorially by a process-free area. The archeopyle is apical, type tA, the operculum is simple and free. In Kofoid notation the paratabulation is 4', 6'', ?c, ?s, 6''', 1p, 1''''.
Dimensions (in µm):
holotyperange
Length of cyst body 63 60 (78) 114
Width of cyst body 65 65 (83) 119
Length of adcingular processes 68-75 48 (69) 119
Number of specimens measured: 10
Stratigraphic occurrence: C. benmorense sp. nov. occurs throughout the Paton Formation in both sections and in the basal Herring Formation in the Ben More section. 1.1 (base of section)-169 m in the Ben More section, 0-296 m in the Kekerengu section. Teratan-Piripauan (middle Coniacian-middle Santonian, Upper Cretaceous) in the Paton Formation, south Marlborough, New Zealand.
Remarks: Although the taxon appears with little morphological variation in the vast majority of samples, specimens were observed with shorter processes and a branching-point positioned half-way along the process (Plate 9, Fig. 5) in the sample at 88 m in the Kekerengu section. However, this deviation from the general morphology is considered an intra-specific variation, and some variation in process length is accepted as well as location of process branching-point. C. benmorense sp. nov. differs from Cymososphaeridium validum Davey, 1982 in being much larger (1.5 x body size, 2-3 x process length of the latter) and by lacking proximal initial branching in the postcingular processes. Furthermore the process terminations in C. benmorense sp. nov. are normally broad and flaring; not thin and cylindrical as in C. validum (compare Davey, 1982, plate 3, figs. 5, 6, 8, 11). The species differs from Cymososphaeridium sp. 1 of Davey (1982) in lacking vacuolate and arcuate processes. The specimens with relatively short processes (Plate 9, Fig. 5) resemble specimens from James Ross Island, Antarctica, assigned to Oligosphaeridium dividuum Williams, 1978 by Olivero and Palamarczuk (1987, plate II, fig. 8).
Holotype: Schiøler and Wilson, 1998, Plate 9, Fig. 3
Paratypes: Schiøler and Wilson, 1998, Plate 9, figs. 1-2, 4, 5
Repository: The palynological type collection, Institute of Geological and Nuclear Sciences, Lower Hutt, New Zealand.
Type locality: Kekerengu section, south Marlborough, New Zealand.
Type stratum: Paton Formation at 180 m on log P30c17. Upper Teratan (Upper Coniacian).
Derivation of name: After the Ben More Stream, south Marlborough, New Zealand.
Diagnosis: Large skolochorate gonyaulacoid cyst carrying 18 solid or extremely thick-walled intraplate processes (loisthocyst: 14, operculum: 4). Paracingular processes absent. Processes branch up to three times and form open flaring to funnel-shaped terminations. Archeopyle apical, type tA, operculum bears four processes, is simple and free. Paratabulation: 4', 6'', ?c, ?s, 6''', 1p, 1''''.
Description: Two-layered skolochorate gonyaulacoid cyst. The wall layers are normally closely appressed and appear as one. The phragm of the cyst body is thin and smooth (phragm thickness: <0.5 µm). Fourteen intraplate processes arise from the loisthocyst. The paracingulum is process-free. Four intraplate processes arise from the operculum (Plate 9, Fig. 6). All processes branch distally one, two and rarely three times and form broad flaring to funnel-shaped terminations. Normally, the branching occurs in the distal fourth to fifth of the process, but in extreme cases the branching may occur half way along the process. The process wall is thick and the processes appear solid; however, on some specimens a small triangular pericoel is developed at the base of some processes, revealing the presence of two wall layers (Plate 9, figs. 1, 4). Likewise, a narrow channel is sometimes visible within the distal half of the process, descending from the process termination and steadily narrowing until the process walls merge and the channel disappears (Plate 9, Fig. 7). The parasulcus is not indicated. The paracingulum is indicated equatorially by a process-free area. The archeopyle is apical, type tA, the operculum is simple and free. In Kofoid notation the paratabulation is 4', 6'', ?c, ?s, 6''', 1p, 1''''.
Dimensions (in µm):
holotyperange
Length of cyst body 63 60 (78) 114
Width of cyst body 65 65 (83) 119
Length of adcingular processes 68-75 48 (69) 119
Number of specimens measured: 10
Stratigraphic occurrence: C. benmorense sp. nov. occurs throughout the Paton Formation in both sections and in the basal Herring Formation in the Ben More section. 1.1 (base of section)-169 m in the Ben More section, 0-296 m in the Kekerengu section. Teratan-Piripauan (middle Coniacian-middle Santonian, Upper Cretaceous) in the Paton Formation, south Marlborough, New Zealand.
Remarks: Although the taxon appears with little morphological variation in the vast majority of samples, specimens were observed with shorter processes and a branching-point positioned half-way along the process (Plate 9, Fig. 5) in the sample at 88 m in the Kekerengu section. However, this deviation from the general morphology is considered an intra-specific variation, and some variation in process length is accepted as well as location of process branching-point. C. benmorense sp. nov. differs from Cymososphaeridium validum Davey, 1982 in being much larger (1.5 x body size, 2-3 x process length of the latter) and by lacking proximal initial branching in the postcingular processes. Furthermore the process terminations in C. benmorense sp. nov. are normally broad and flaring; not thin and cylindrical as in C. validum (compare Davey, 1982, plate 3, figs. 5, 6, 8, 11). The species differs from Cymososphaeridium sp. 1 of Davey (1982) in lacking vacuolate and arcuate processes. The specimens with relatively short processes (Plate 9, Fig. 5) resemble specimens from James Ross Island, Antarctica, assigned to Oligosphaeridium dividuum Williams, 1978 by Olivero and Palamarczuk (1987, plate II, fig. 8).