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Hystrichosphaeridium langii

Hystrichosphaeridium langii Wall, 1965a, p.165, pl.6, figs.9–11; pl.9, fig.9. Emendations: Morbey, 1975, p.41–42, as Hystrichosphaeridium langii; Below, 1987a, p.70–71, as Beaumontella langii.

Now Beaumontella. Originally Hystrichosphaeridium, subsequently Polysphaeridium?, thirdly Dapsilidinium?, fourthly (and now) Beaumontella.

Holotype: Wall, 1965, pl.6, fig.9, pl.9, fig.9
Locus typicus: Britain
Stratum typicum: Hettangian-Sinemurian

Original diagnosis: Wall 1965, p. 165
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
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.

Emended diagnosis: Morbey, 1975, p. 41-42
Cyst chorate, cylindroidal, spheroidal, ovoidal or spherical. Wall thin, microgranulate, rarely folded. Archaeopyle apical, represented by rupture of cyst at apex of longitudinal axis, not discernible on all specimens. Processes hollow, compound or simple heteromorphic, possibly open distally, generally of equal
length per individual, 25-75 in number, less than or equal to 50% of cyst length/diameter in length. Process bases constricted to widely curved, seldom confluent; stems cylindrical, tapered, conical, or lagenate, often slender and sinuous in development; terminations seemingly bifid, bifurcate, or trifurcate, with pointed or rounded tips-occasionally terminations collarette (ectophragm), or simple with truncate or pointed tips (?preservation). Dimensions: cyst legth/diameter 14-30 µm; breadth 12-25 µm; process length 3-10 µm, diameter up to 2 µm; cyst length:breadth 1:1-3:1.

Affinities:
Wall, 1965, p. 165: Hystrichosphaeridium langii is similar to H. capitatum Cookson and Eisenack and H. rhabdophorum Valensi, but is smaller and bears less
numerous spines.
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