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Hystrichokolpoma stellatum
Hystrichokolpoma stellatum (Maier, 1959) Truswell et al., 1985
Originally Hystrichosphaeridium, subsequently Hystrichosphaeridium?, thirdly Florentinia, fourthly Hystrichokolpoma.
Tax. jr. synonym of Hystrichokolpoma rigaudiae Deflandre and Cookson, 1955, according to Sarjeant, 1983.
Holotype: Maier, 1959, pl.33, fig.3; Sarjeant, 1983, pl.7, figs.1-2
Age: Middle Oligocene-Middle Miocene
Original description: Maier, 1959, p. 320
Diagnosis: A species of the genus Hystrichosphaeridium with the following special characteristics: On the spherical body, broad and narrow processes are arranged regularly in a triangular form.
Description: The spherical shell has a membrane with a fibrous structure. Broad and narrow processes are symmetrically arranged. If the broad processes, arranged in a plane, are connected, then an isosceles triangle arises. This figure repeats slightly displaced in other planes. The slender processes stand on the sides of the triangles. The paratypes are not as regularly developed. 3 specimens.
Dimensions: Sphere diameter 62 Ám, length of broad processes 34 Ám, length of slender processes 38 Ám.
Affinities:
Maier, 1959, p. 321: The combination of broad and slender processes has been described repeatedly. Most conspicuous is the similarity with Hystricchosphaera bulbosa (Ehrenberg). However, in that species the bottle-shaped proccesses taper more strongly and are distally hardly serrate, whilst H. stellatum has distally serrate proceses, which widen in a funnel-like fashion. A relation with Hystrichosphaeridium biformoides Eisenack musst be excluded. The wide processes of that species are distally closed, those of H. stellatum open. The broad processes of H. biformoides Eisenack bear accessory tips and the slender appendices are partly pointed, partly branched. In H. flosculus Deflandre and H. truncigerum Deflandre the wide protruberances are cylindrical and partly sculptured, so that here as well a direct connection must be excluded.
Originally Hystrichosphaeridium, subsequently Hystrichosphaeridium?, thirdly Florentinia, fourthly Hystrichokolpoma.
Tax. jr. synonym of Hystrichokolpoma rigaudiae Deflandre and Cookson, 1955, according to Sarjeant, 1983.
Holotype: Maier, 1959, pl.33, fig.3; Sarjeant, 1983, pl.7, figs.1-2
Age: Middle Oligocene-Middle Miocene
Original description: Maier, 1959, p. 320
Diagnosis: A species of the genus Hystrichosphaeridium with the following special characteristics: On the spherical body, broad and narrow processes are arranged regularly in a triangular form.
Description: The spherical shell has a membrane with a fibrous structure. Broad and narrow processes are symmetrically arranged. If the broad processes, arranged in a plane, are connected, then an isosceles triangle arises. This figure repeats slightly displaced in other planes. The slender processes stand on the sides of the triangles. The paratypes are not as regularly developed. 3 specimens.
Dimensions: Sphere diameter 62 Ám, length of broad processes 34 Ám, length of slender processes 38 Ám.
Affinities:
Maier, 1959, p. 321: The combination of broad and slender processes has been described repeatedly. Most conspicuous is the similarity with Hystricchosphaera bulbosa (Ehrenberg). However, in that species the bottle-shaped proccesses taper more strongly and are distally hardly serrate, whilst H. stellatum has distally serrate proceses, which widen in a funnel-like fashion. A relation with Hystrichosphaeridium biformoides Eisenack musst be excluded. The wide processes of that species are distally closed, those of H. stellatum open. The broad processes of H. biformoides Eisenack bear accessory tips and the slender appendices are partly pointed, partly branched. In H. flosculus Deflandre and H. truncigerum Deflandre the wide protruberances are cylindrical and partly sculptured, so that here as well a direct connection must be excluded.