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Hystrichokolpoma tridactylites
Hystrichokolpoma tridactylites (Valensi, 1955) Williams and Downie, 1966
Combination not validly published since Williams and Downie, 1966, did not fully reference the basionym.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Hystrichokolpoma (combination not validly published), fourthly Achomosphaera, fifthly Silicisphaera, sixthly (and now) Florentinia.
Holotype: Valensi, 1955, fig.1D
Age: Cretaceous
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Original description: [Valensi, 1955a, p. 37-38] (translated from French):
Holotype (unique): Cretaceous flint from the Venesmes.
The shell, with an ellipsoidal, almost quadrangular outline, bears about fifteen processes, simple or with three branches and always slightly longer than half of its major axis. The insertion of these processes on the surface of the shell is marked by a dark line; it is surrounded by a system of radiating striae resolving into fine aligned granulations and circumscribed by a polygon of denser and diversely arranged granulations. This structure is not without analogy with that of the forms related to Hystrichosphaeridium tubiferum (Ehr.) Defl. and with that of Hystrichosphaeridium horridum Defl. and Hystrichosphaeridium ferox Defl.
The simple processes are conical in shape. Those with three branches have a base that seemed to me to be a flattened blade, relatively wide, longitudinally striated and sometimes openwork.
The terminal branches arise at mid-length of processes; they are generally arranged in a triangle and rarely align in the same plane; they are straight, sometimes curved and can end in fine spines.
The surface of the shell is granular; the color is dark brown.
The total span of Hystrichosphaeridium tridactylites is 60 to 90 μ; the major axis of the shell measures 40 μ and its minor axis 33 μ. The processes are 20 to 25 μ long.
Hystrichosphaeridium tridactylites is similar to Hystrichosphaeridium ferox from the Cretaceous in its general appearance; it differs, however, in the shape and length of its processes.
Combination not validly published since Williams and Downie, 1966, did not fully reference the basionym.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Hystrichokolpoma (combination not validly published), fourthly Achomosphaera, fifthly Silicisphaera, sixthly (and now) Florentinia.
Holotype: Valensi, 1955, fig.1D
Age: Cretaceous
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Original description: [Valensi, 1955a, p. 37-38] (translated from French):
Holotype (unique): Cretaceous flint from the Venesmes.
The shell, with an ellipsoidal, almost quadrangular outline, bears about fifteen processes, simple or with three branches and always slightly longer than half of its major axis. The insertion of these processes on the surface of the shell is marked by a dark line; it is surrounded by a system of radiating striae resolving into fine aligned granulations and circumscribed by a polygon of denser and diversely arranged granulations. This structure is not without analogy with that of the forms related to Hystrichosphaeridium tubiferum (Ehr.) Defl. and with that of Hystrichosphaeridium horridum Defl. and Hystrichosphaeridium ferox Defl.
The simple processes are conical in shape. Those with three branches have a base that seemed to me to be a flattened blade, relatively wide, longitudinally striated and sometimes openwork.
The terminal branches arise at mid-length of processes; they are generally arranged in a triangle and rarely align in the same plane; they are straight, sometimes curved and can end in fine spines.
The surface of the shell is granular; the color is dark brown.
The total span of Hystrichosphaeridium tridactylites is 60 to 90 μ; the major axis of the shell measures 40 μ and its minor axis 33 μ. The processes are 20 to 25 μ long.
Hystrichosphaeridium tridactylites is similar to Hystrichosphaeridium ferox from the Cretaceous in its general appearance; it differs, however, in the shape and length of its processes.