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Dapsilidinium langii

Dapsilidinium? langii (Wall, 1965) Lentin and Williams, 1981

Now Beaumontella. Originally Hystrichosphaeridium, subsequently Polysphaeridium?, thirdly Dapsilidinium?, fourthly (and now) Beaumontella.
At the time of the transfer, Lentin and Williams, 1981, questionably included this species in Dapsilidinium.
Morbey, 1975, emended the diagnosis of this species, as Hystrichosphaeridium langii.
Holotype: Wall, 1965, pl.9, fig.9
Locus typicus: England
Stratum typicum: Hettangian-Sinemurian

Original diagnosis: Wall 1965, p. 165: Hystrichosphaeridium langii
Hystrichosphaeridium langii a small species of Hystrichosphaeridium with a microgranular test and a relatively small number (25-40) of short, open appendages with a minute lateral rim or divided tip.

Original description: Wall 1965, p. 165: Hystrichosphaeridium langii
The test is round, ovoid or subrectangular in outline, its wall thin and microgranular. approximately twenty spines are visible in optical section, and they are equal to approximately 25 percent of the test diameter in length. The spines are small, and precise determination of the nature of the spine tip is difficult. They usually appear to be minutely bifurcate or trifurcate or even to produce several projections. Often the test is broken at one end, but not regularly so.
Dimensions: maximum test dimensions 21-32 µm, spines 3-6.5 µm; holotype test 24x22 µm, spines 5.5 µm maximum.
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