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Dapsilidinium fucosum
Dapsilidinium? fucosum (Valensi, 1955) Lentin and Williams, 1981
Holotype: Valensi, 1955a, text-fig.2b; Fauconnier and Masure, pl.52, figs.8-11. Originally Micrhystridium, subsequently Hystrichosphaeridium, thirdly Polysphaeridium?, fourthly Dapsilidinium?, fifthly (and now) Litosphaeridium. Taxonomic junior synonyms (at specific rank): Hystrichosphaeridium tubiferum subsp. brevispinum, according to Below (1982c, p.29); Hystrichosphaeridium (as and now Litosphaeridium) arundum, according to Below (1982c, p.29) - however, Lentin and Williams (1985, p.190,227) retained Hystrichosphaeridium tubiferum subsp. brevispinum and Litosphaeridium arundum. Age: Late Cretaceous.
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Original description: [Valensi, 1955] (translated from French):
Holotype (unique): Cretaceous flint from Venesmes.
The ovoid shell has about twenty tube-like processes whose length is between a third and a half of its diameter. These tubes are hollow, of circular section, and their cavity does not seem to communicate with that of the shell; slightly widened at their base, they flare out a little at their end. The surface of the shell is granular and the color light brown.
The size is 20 to 24 μ for the shell alone, 7 to 10 μ for the processes and 30 to 35 μ for the total span.
Despite the absence of spines on the edges of the terminal funnel of the processes, Micrhystridium fucosum is undoubtedly a "Tubifer", but its small size and short processes distance it from Hystrichosphaeridium tubiferum and its more than double size, from Micrhystridium paulinae Val. of the Jurassic.
Holotype: Valensi, 1955a, text-fig.2b; Fauconnier and Masure, pl.52, figs.8-11. Originally Micrhystridium, subsequently Hystrichosphaeridium, thirdly Polysphaeridium?, fourthly Dapsilidinium?, fifthly (and now) Litosphaeridium. Taxonomic junior synonyms (at specific rank): Hystrichosphaeridium tubiferum subsp. brevispinum, according to Below (1982c, p.29); Hystrichosphaeridium (as and now Litosphaeridium) arundum, according to Below (1982c, p.29) - however, Lentin and Williams (1985, p.190,227) retained Hystrichosphaeridium tubiferum subsp. brevispinum and Litosphaeridium arundum. Age: Late Cretaceous.
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Original description: [Valensi, 1955] (translated from French):
Holotype (unique): Cretaceous flint from Venesmes.
The ovoid shell has about twenty tube-like processes whose length is between a third and a half of its diameter. These tubes are hollow, of circular section, and their cavity does not seem to communicate with that of the shell; slightly widened at their base, they flare out a little at their end. The surface of the shell is granular and the color light brown.
The size is 20 to 24 μ for the shell alone, 7 to 10 μ for the processes and 30 to 35 μ for the total span.
Despite the absence of spines on the edges of the terminal funnel of the processes, Micrhystridium fucosum is undoubtedly a "Tubifer", but its small size and short processes distance it from Hystrichosphaeridium tubiferum and its more than double size, from Micrhystridium paulinae Val. of the Jurassic.