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Glaphyrocysta extensa
Glaphyrocysta extensa Fensome et al., 2009, p.32, pl.4, figs.c–h.
Holotype: Fensome et al., 2009, pl.4, figs.c–d.
Age: youngest occurrence, middle Priabonian.
Original description (Fensome et al., 2009):
Glaphyrocysta extensa sp. nov. (Plate 4, figs c-h)
HOLOTYPE. Plate 4, figs c-d; from a sidewall core sample at 488.3 m (1602 feet) in Demascota G-32 well; GSC type collection no. 130198, sample P37542, slide 01, co-ordinates 14.8 × 103.6, England Finder O47/3; length of central body 53 μm, width of central body 61 μm, maximum length/height of processes and crests 23 μm. The age determined for the sample from which the holotype was recovered is Lutetian (Middle Eocene).
DERIVATION OF NAME. The epithet is derived from the Latin word 'extensivus', meaning 'wide' or 'stretched out', in ref erence to the broad membranous arch-like developments that are distinctive of this species.
DESCRIPTION. A species of Glaphyrocysta in which the or nament consists of a mixture of processes and membranes, including the development of some usually membranous, arch-like trabecula that join adjacent processes, especially towards the antapex. Process distribution is not generally strongly marginate, and does not obviously reflect tabulation. Isolated processes are fine and acuminate, and may be joined along their length by trabecula.
SIZE. Length of central body 53(65)79 μm, width of central body 61(79)92 μm, maximum length/height of processes and crests 23(36)44μm; 3 specimens measured.
AGE ON SCOTIAN MARGIN. LAD: middle Priabonian (Late Eocene).
REMARKS. Areoligera undulata is very similar to Glaphyrocysta extensa, especially in the development of arch-like trabecula, but has processes clearly arranged into basally joined complexes. The outline of Glaphyrocysta extensa is scalloped, rather than entire as in Glaphyrocysta exuberans and Glaphyrocysta laciniiformis. Glaphyrocysta extensa is similar to Glaphyrocysta spineta, but in the protologue of Glaphyrocysta spineta, Eaton (1976) emphasised the 'numer ous acuminate spines' emanating from the arched trabecula; in Glaphyrocysta extensa, such spines are present but are not particularly numerous or noteworthy.
Holotype: Fensome et al., 2009, pl.4, figs.c–d.
Age: youngest occurrence, middle Priabonian.
Original description (Fensome et al., 2009):
Glaphyrocysta extensa sp. nov. (Plate 4, figs c-h)
HOLOTYPE. Plate 4, figs c-d; from a sidewall core sample at 488.3 m (1602 feet) in Demascota G-32 well; GSC type collection no. 130198, sample P37542, slide 01, co-ordinates 14.8 × 103.6, England Finder O47/3; length of central body 53 μm, width of central body 61 μm, maximum length/height of processes and crests 23 μm. The age determined for the sample from which the holotype was recovered is Lutetian (Middle Eocene).
DERIVATION OF NAME. The epithet is derived from the Latin word 'extensivus', meaning 'wide' or 'stretched out', in ref erence to the broad membranous arch-like developments that are distinctive of this species.
DESCRIPTION. A species of Glaphyrocysta in which the or nament consists of a mixture of processes and membranes, including the development of some usually membranous, arch-like trabecula that join adjacent processes, especially towards the antapex. Process distribution is not generally strongly marginate, and does not obviously reflect tabulation. Isolated processes are fine and acuminate, and may be joined along their length by trabecula.
SIZE. Length of central body 53(65)79 μm, width of central body 61(79)92 μm, maximum length/height of processes and crests 23(36)44μm; 3 specimens measured.
AGE ON SCOTIAN MARGIN. LAD: middle Priabonian (Late Eocene).
REMARKS. Areoligera undulata is very similar to Glaphyrocysta extensa, especially in the development of arch-like trabecula, but has processes clearly arranged into basally joined complexes. The outline of Glaphyrocysta extensa is scalloped, rather than entire as in Glaphyrocysta exuberans and Glaphyrocysta laciniiformis. Glaphyrocysta extensa is similar to Glaphyrocysta spineta, but in the protologue of Glaphyrocysta spineta, Eaton (1976) emphasised the 'numer ous acuminate spines' emanating from the arched trabecula; in Glaphyrocysta extensa, such spines are present but are not particularly numerous or noteworthy.