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Micrhystridium mastigophorum
Original description: [Valensi, 1949, p. 547-548] (translated from French):
Micrhystridium mastigophorum nov. sp.
7 and. 8 of fig. 5.
Holotype: Lower Bathonian, flint from the Mouchedune farm near Saint-Benoit (Vienne).
The shell (7 of fig. 5) is oval in shape and has a slightly undulating outline; its surface is covered with numerous longitudinal and parallel striations cut by three transverse lines, one equatorial, the other two polar; it bears about fifteen flagelliform processes (8 of fig. 5). The large diameter of the shell is 16 μ, the small one 14 μ, the equatorial transverse line is separated by a distance of 7 μ from the transverse line of the upper pole, and 4 μ from that of the lower pole, the striations perpendicular to these lines are some thin, others distinctly thicker, they circumscribe elongated polygonal spaces; their density is about fifteen on a length of 10 μ of the transverse line, and in general they are
found one opposite the other on either side of this line. The median region of the fields is often occupied by a series of points; I observed the insertion of a flagelliform process on one of these points; but I could not distinguish exactly the connections from the others which most often have a length varying from 5 to 10 μ; some are shorter (up to 2 μ), but they are certainly damaged; all are variously curved, convoluted and folded back on themselves, recalling in this the true flagella of the Ophiobolaceae of the Cretaceous flints. Until further information it does not seem that they are, in Micrhystridium mastigophorum, organelles similar to flagella, but rather superficial appendages not endowed with motility, as has already been observed in certain current microplanktonites.
The color of this organism is dark brown.
This species is so far represented by a single specimen: it has a very particular appearance that is not found in any of the forms described so far.
Micrhystridium mastigophorum nov. sp.
7 and. 8 of fig. 5.
Holotype: Lower Bathonian, flint from the Mouchedune farm near Saint-Benoit (Vienne).
The shell (7 of fig. 5) is oval in shape and has a slightly undulating outline; its surface is covered with numerous longitudinal and parallel striations cut by three transverse lines, one equatorial, the other two polar; it bears about fifteen flagelliform processes (8 of fig. 5). The large diameter of the shell is 16 μ, the small one 14 μ, the equatorial transverse line is separated by a distance of 7 μ from the transverse line of the upper pole, and 4 μ from that of the lower pole, the striations perpendicular to these lines are some thin, others distinctly thicker, they circumscribe elongated polygonal spaces; their density is about fifteen on a length of 10 μ of the transverse line, and in general they are
found one opposite the other on either side of this line. The median region of the fields is often occupied by a series of points; I observed the insertion of a flagelliform process on one of these points; but I could not distinguish exactly the connections from the others which most often have a length varying from 5 to 10 μ; some are shorter (up to 2 μ), but they are certainly damaged; all are variously curved, convoluted and folded back on themselves, recalling in this the true flagella of the Ophiobolaceae of the Cretaceous flints. Until further information it does not seem that they are, in Micrhystridium mastigophorum, organelles similar to flagella, but rather superficial appendages not endowed with motility, as has already been observed in certain current microplanktonites.
The color of this organism is dark brown.
This species is so far represented by a single specimen: it has a very particular appearance that is not found in any of the forms described so far.