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Hystrichosphaeridium pumile
Hystrichosphaeridium pumile (O.Wetzel, 1932 ex O.Wetzel, 1933) Deflandre, 1937
Name illegitimate; nomenclatural jr. synonym of Hystrichosphaera longispinosa forma longispinosa, the potential autonym since, in proposing Hystrichosphaera longispinosa forma pumilis, O.Wetzel, 1933, included in synonymy the holotype of the species.
See also Hystrichosphaera longispinosa forma pumilis (name illegitimate), Micrhystridium pumile (name illegitimate), Diacrocanthidium? pumile (name illegitimate) and Baltisphaeridium pumile (name illegitimate).
Deflandre, 1937, proposed the elevation of this taxon to specific rank as Hystrichosphaeridium pumile.
The name Hystrichosphaera longispinosa forma pumilis, although accompanied by a description, was not validly published by O. Wetzel, 1932, since the generic name Hystrichosphaera was not validated until 1933.
In validly publishing, but not legitimizing, the name Hystrichosphaera longispinosa forma pumilis, O. Wetzel, 1933, illustrated only one specimen but listed in synonymy several more, including the holotype of the species; he did not designate any of these specimens as holotype.
Based on reexamination of the single specimen illustrated by O. Wetzel, 1933, which he indicated as holotype, Sarjeant, 1985, proposed the transfer of this taxon (questionably) to Diacrocanthidium Deflandre and Foucher, 1967.
Holotype: O.Wetzel, 1933, pl.4, fig.24 (designated by Sarjeant, 1985)
Age: Late Cretaceous (based on material from an erratic)
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Emended description: [Valensi, 1949, p. 541] (translated from French):
Plesiotype: Lower Bathonian, flint from the Mouchedune farm near Saint-Benoît (Vienne).
The fairly large shell, with a roughly hexagonal outline and a smooth surface, bears about thirty long processes (fig. 2). These processes are hollow, they are slightly but clearly widened at their base and their cavity is separated from that of the shell; generally straight, they can also be curved like a sabre blade, or even spiraled, as a result of alteration during fossilization, their end is very tapered when they are intact. The diameter of the shell varies from 26 μ to 30 μ, the longest processes, which are also the most numerous, measure 30 μ, that is to say the diameter of the shell, the others are only about twenty microns long. The color of the only specimen observed is dark brown.
This species, a plesiotype of which was described by M. Deflandre in the Cretaceous [5], presents great analogies with Hystrichosphaeridium longispinosum described by Eisenack in the Silurian of the Baltic domain. However, it is much smaller, and its less regularly shaped processes offer a more convoluted appearance and are less regularly distributed around the periphery of the shell. If these are indeed, in the various stages, forms that are actually related, this species would appear to have evolved very little over geological time and would possess only a mediocre stratigraphic value.
Name illegitimate; nomenclatural jr. synonym of Hystrichosphaera longispinosa forma longispinosa, the potential autonym since, in proposing Hystrichosphaera longispinosa forma pumilis, O.Wetzel, 1933, included in synonymy the holotype of the species.
See also Hystrichosphaera longispinosa forma pumilis (name illegitimate), Micrhystridium pumile (name illegitimate), Diacrocanthidium? pumile (name illegitimate) and Baltisphaeridium pumile (name illegitimate).
Deflandre, 1937, proposed the elevation of this taxon to specific rank as Hystrichosphaeridium pumile.
The name Hystrichosphaera longispinosa forma pumilis, although accompanied by a description, was not validly published by O. Wetzel, 1932, since the generic name Hystrichosphaera was not validated until 1933.
In validly publishing, but not legitimizing, the name Hystrichosphaera longispinosa forma pumilis, O. Wetzel, 1933, illustrated only one specimen but listed in synonymy several more, including the holotype of the species; he did not designate any of these specimens as holotype.
Based on reexamination of the single specimen illustrated by O. Wetzel, 1933, which he indicated as holotype, Sarjeant, 1985, proposed the transfer of this taxon (questionably) to Diacrocanthidium Deflandre and Foucher, 1967.
Holotype: O.Wetzel, 1933, pl.4, fig.24 (designated by Sarjeant, 1985)
Age: Late Cretaceous (based on material from an erratic)
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Emended description: [Valensi, 1949, p. 541] (translated from French):
Plesiotype: Lower Bathonian, flint from the Mouchedune farm near Saint-Benoît (Vienne).
The fairly large shell, with a roughly hexagonal outline and a smooth surface, bears about thirty long processes (fig. 2). These processes are hollow, they are slightly but clearly widened at their base and their cavity is separated from that of the shell; generally straight, they can also be curved like a sabre blade, or even spiraled, as a result of alteration during fossilization, their end is very tapered when they are intact. The diameter of the shell varies from 26 μ to 30 μ, the longest processes, which are also the most numerous, measure 30 μ, that is to say the diameter of the shell, the others are only about twenty microns long. The color of the only specimen observed is dark brown.
This species, a plesiotype of which was described by M. Deflandre in the Cretaceous [5], presents great analogies with Hystrichosphaeridium longispinosum described by Eisenack in the Silurian of the Baltic domain. However, it is much smaller, and its less regularly shaped processes offer a more convoluted appearance and are less regularly distributed around the periphery of the shell. If these are indeed, in the various stages, forms that are actually related, this species would appear to have evolved very little over geological time and would possess only a mediocre stratigraphic value.