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Areosphaeridium capricornum
Areosphaeridium capricornum, (Cookson and Eisenack, 1965), Stover and Evitt, 1978
Originally Cordosphaeridium, subsequently Systematophora?, thirdly (and now) Areosphaeridium.
Tax. jr. synonym of Areosphaeridium dictyostilum (Menendez, 1965) Sarjeant, 1981, according to Sarjeant, 1981. Lentin and Williams, 1985, retained Areosphaeridium capricornum as a separate species.
Holotype: Cookson and Eisenack, 1965, pl.15, fig.7
Locus typicus: SW. Victoria, Australia
Stratum typicum: Late Eocene
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Original description as Cordosphaeridium capricornum: [Cookson and Eisenack, 1965, p. 128]:
Description:
Shell approximately spherical with numerous radially arranged appendages of characteristic form which vary in number in individual specimens and in size, form, and structure in one and the same specimen. All are solid; some are simple with unbranched or slightly branched apices or with terminal bifurcations which extend laterally and are upwardly or downwardly curved, others are broadly flattened and perforated to varying degrees with broad apices which narrow gradually as they curve backwards towards the shell. The upper surface of the apices and their extensions are consistently finely denticulate (Pl. 15, fig. 8, 9). The bases of the larger appendages are semicircular to, occasionally, almost circular, and similarly the tips of the apical prolongations sometimes appear to touch but, in reality, are never connected. The appendages are sometimes faintly and longitudinally striated; shorter and more pronounced striations may be evident at or near their points of origin. The surface of the shell is faintly granular.
The archeopyle is apical, the operculum bearing four appendages, two relatively large and two small.
At the antapex an approximately circular area, outlined either completely (Pl. 15, fig. 6) or incompletely by a ridge to which a few small simple appendages may or may not be attached, has been seen. Such an area is suggestive of an antapical field.
Dimensions:
Holotype - overall width c. 78 µm, width of shell c. 52 µm.
Range - overall width c. 70-94 µm, width of shell c. 43-52 µm; appendages c. 18-30 µm long.
Originally Cordosphaeridium, subsequently Systematophora?, thirdly (and now) Areosphaeridium.
Tax. jr. synonym of Areosphaeridium dictyostilum (Menendez, 1965) Sarjeant, 1981, according to Sarjeant, 1981. Lentin and Williams, 1985, retained Areosphaeridium capricornum as a separate species.
Holotype: Cookson and Eisenack, 1965, pl.15, fig.7
Locus typicus: SW. Victoria, Australia
Stratum typicum: Late Eocene
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Original description as Cordosphaeridium capricornum: [Cookson and Eisenack, 1965, p. 128]:
Description:
Shell approximately spherical with numerous radially arranged appendages of characteristic form which vary in number in individual specimens and in size, form, and structure in one and the same specimen. All are solid; some are simple with unbranched or slightly branched apices or with terminal bifurcations which extend laterally and are upwardly or downwardly curved, others are broadly flattened and perforated to varying degrees with broad apices which narrow gradually as they curve backwards towards the shell. The upper surface of the apices and their extensions are consistently finely denticulate (Pl. 15, fig. 8, 9). The bases of the larger appendages are semicircular to, occasionally, almost circular, and similarly the tips of the apical prolongations sometimes appear to touch but, in reality, are never connected. The appendages are sometimes faintly and longitudinally striated; shorter and more pronounced striations may be evident at or near their points of origin. The surface of the shell is faintly granular.
The archeopyle is apical, the operculum bearing four appendages, two relatively large and two small.
At the antapex an approximately circular area, outlined either completely (Pl. 15, fig. 6) or incompletely by a ridge to which a few small simple appendages may or may not be attached, has been seen. Such an area is suggestive of an antapical field.
Dimensions:
Holotype - overall width c. 78 µm, width of shell c. 52 µm.
Range - overall width c. 70-94 µm, width of shell c. 43-52 µm; appendages c. 18-30 µm long.