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Litosphaeridium truncigerum
Litosphaeridium? truncigerum (Deflandre, 1937) Davey and Williams, 1969
Now Raetiaedinium. Originally Hystrichosphaeridium, subsequently Litosphaeridium?, thirdly Cordosphaeridium, fourthly Exochosphaeridium, fifthly Pervosphaeridium, sixthly Tityrosphaeridium?, seventhly Florentinia, eighthly Pervosphaeridium?, ninethly (and now) Raetiaedinium.
Tax. jr. synonym of Xanthidium (now Hystrichokolpoma) crassipes Reade, 1839, by implication, according to Yun, 1981, who considered Litosphaeridium? (as Pervosphaeridium) truncigerum to be the sr. synonym. Lentin and Williams, 1985, retained Lithosphaeridium (as Pervosphaeridium) truncigerum as a separate species.
At the time of the transfer, Davey and Williams, 1969, questionably included this species in Litosphaeridium.
Lentin and Williams, 1973, retained this species in Hystrichosphaeridium Deflandre, 1937.
This combination was not validly published in Davey and Williams, 1966, who questionably transferred the species to Litosphaeridium, but did not fully reference the basionym.
Holotype: Deflandre, 1937, pl.13 [al. pl.10], fig.6
Age: Senonian
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Original description: [Deflandre, 1937b] (translated from French):
HYSTRICHOSPHERIDIUM TRUNCIGERUM n. sp.
PI. XIIIL, fig. 6, 7.
Holotype: AF 38, flint S. 35, pebble, Paris.
Paratypes: AF 40, AF 42, from the same flint; AJ 37, from flint S. 17, AH 38, AH 49, AH 68, from flint S. 48, both, pebbles, near Paris.
The shell, roughly spherical, bears appendages of two kinds: some have pointed horns, others are widely open cone-like truncated cones, the edges of which are generally jagged or denticulated. These cone-like truncated cones appear stretched and bear slight striations parallel to their axis. From their base, radiating striations of varying degrees of severity extend onto the shell itself, joining similar striations emanating from the neighboring cone truncates. Furthermore, the surface of the shell is finely punctuated. Despite individual variations, the general appearance of the individuals remains remarkably constant, and this species is very easy to distinguish from all others. The average diameter of the shell alone is about forty microns; with the longest processes, it reaches approximately 75 to 80 microns. The appendages other than the cone truncates generally have the shape of blunt-tipped horns; some are occasionally forked.
Hystrichosphæridium truncigerum is not very rare and has already been found in several flint pebbles in Paris or the surrounding area.
Now Raetiaedinium. Originally Hystrichosphaeridium, subsequently Litosphaeridium?, thirdly Cordosphaeridium, fourthly Exochosphaeridium, fifthly Pervosphaeridium, sixthly Tityrosphaeridium?, seventhly Florentinia, eighthly Pervosphaeridium?, ninethly (and now) Raetiaedinium.
Tax. jr. synonym of Xanthidium (now Hystrichokolpoma) crassipes Reade, 1839, by implication, according to Yun, 1981, who considered Litosphaeridium? (as Pervosphaeridium) truncigerum to be the sr. synonym. Lentin and Williams, 1985, retained Lithosphaeridium (as Pervosphaeridium) truncigerum as a separate species.
At the time of the transfer, Davey and Williams, 1969, questionably included this species in Litosphaeridium.
Lentin and Williams, 1973, retained this species in Hystrichosphaeridium Deflandre, 1937.
This combination was not validly published in Davey and Williams, 1966, who questionably transferred the species to Litosphaeridium, but did not fully reference the basionym.
Holotype: Deflandre, 1937, pl.13 [al. pl.10], fig.6
Age: Senonian
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Original description: [Deflandre, 1937b] (translated from French):
HYSTRICHOSPHERIDIUM TRUNCIGERUM n. sp.
PI. XIIIL, fig. 6, 7.
Holotype: AF 38, flint S. 35, pebble, Paris.
Paratypes: AF 40, AF 42, from the same flint; AJ 37, from flint S. 17, AH 38, AH 49, AH 68, from flint S. 48, both, pebbles, near Paris.
The shell, roughly spherical, bears appendages of two kinds: some have pointed horns, others are widely open cone-like truncated cones, the edges of which are generally jagged or denticulated. These cone-like truncated cones appear stretched and bear slight striations parallel to their axis. From their base, radiating striations of varying degrees of severity extend onto the shell itself, joining similar striations emanating from the neighboring cone truncates. Furthermore, the surface of the shell is finely punctuated. Despite individual variations, the general appearance of the individuals remains remarkably constant, and this species is very easy to distinguish from all others. The average diameter of the shell alone is about forty microns; with the longest processes, it reaches approximately 75 to 80 microns. The appendages other than the cone truncates generally have the shape of blunt-tipped horns; some are occasionally forked.
Hystrichosphæridium truncigerum is not very rare and has already been found in several flint pebbles in Paris or the surrounding area.