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Hystrichosphaeridium centrocarpum var. centrocarpum
Hystrichosphaeridium centrocarpum var. centrocarpumvar
Autonym, now redundant.
Holotype: Deflandre and Cookson, 1955, pl.8, figs.3-4
Locus typicus: Balcombe Bay, Victoria, Australia
Stratum typicum: Middle Miocene
Original description: Deflandre and Cookson, 1955, p. 273
Shell globular, more or less ellipsoidal (probably by deformation), covered with numerous straight, slender processes placed irregulary or with a certain alignment. Processes solid, showing radiating fibrils at their point of insertion on the shell, which is clearly ornamented with a fine reticulum. The slightly widened apices of the processes are fringed with 10 or more small curved spines (this structure is only visible with a high-powered objective).
Dimensions: Diameter of shell 54-80 Ám, length of processes 13-18 Ám, total diameter c. 97-115 Ám.
As a result of the relative thinness of the shell membrane none of the specimens has been completely intact. Most of the examples have a large irregular or more or less angular opening.
Affinities:
Deflandre and Cookson, 1955, p. 273: H. centrocarpum, in spite of its generally similar appearance, does not belong to the species group of H. recurvatum Delf. - H. major Lej.-Carp. known from the European Cretaceous flints. In these species the hollow processes have a quite different structure.
Autonym, now redundant.
Holotype: Deflandre and Cookson, 1955, pl.8, figs.3-4
Locus typicus: Balcombe Bay, Victoria, Australia
Stratum typicum: Middle Miocene
Original description: Deflandre and Cookson, 1955, p. 273
Shell globular, more or less ellipsoidal (probably by deformation), covered with numerous straight, slender processes placed irregulary or with a certain alignment. Processes solid, showing radiating fibrils at their point of insertion on the shell, which is clearly ornamented with a fine reticulum. The slightly widened apices of the processes are fringed with 10 or more small curved spines (this structure is only visible with a high-powered objective).
Dimensions: Diameter of shell 54-80 Ám, length of processes 13-18 Ám, total diameter c. 97-115 Ám.
As a result of the relative thinness of the shell membrane none of the specimens has been completely intact. Most of the examples have a large irregular or more or less angular opening.
Affinities:
Deflandre and Cookson, 1955, p. 273: H. centrocarpum, in spite of its generally similar appearance, does not belong to the species group of H. recurvatum Delf. - H. major Lej.-Carp. known from the European Cretaceous flints. In these species the hollow processes have a quite different structure.