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Beaumontella delicata
Beaumontella? delicata, (Wall, 1965), Below, 1987
Beaumontella delicata was first described as Baltisphaeridium delicatum, Wall, new species Plate 1, figures 11-13 ; plate 7, figure 6
Originally Baltisphaeridium, subsequently (and now) Beaumontella?; see also Solisphaeridium (combination not validly published). At the time of the transfer, Below, 1987, questionably included this species in Beaumontella and noted that it may represent acritarchs.
Holotype: Wall, 1965, pl.1, fig.11
Occurrence: Lower Lias (S. angulala to C. turneri Zones), Lyme Regis, Dorset.
Age: Hettangian-Sinemurian
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Original description as Baltisphaeridium delicatum: [Wall, 1965]:
Diagnosis:
An acritarch species with a delicate, ovoid to globular test bearing 20 to 40 simple, hollow spines of medium length.
Description:
The test wall is very thin and easily folded. Its spines are hollow, mostly straight, and taper from bases 2 to 3 a wide to minutely rounded tips, which may be solid. Individual spines vary between one-fifth and one-half of the maximum test dimension in length. Occasionally the test is broken at one end; this is not a constant feature but is due to the delicate nature of the test wall.
Dimensions:
Test only, 16 X 15 µm to 24 X 17 µm; spines 2.5 to 9 µm: holotype 24 X 16 µm, spines 4 µm. (twenty-five specimens).
Affinities:
This species closely resembles Baltisphaeridium brevispinosum Eisenack var. wenlockensts Downie , 1959, p. 59, from the Silurian Wenlock Shale in England. I n addition to their considerably different geological ages, the Liassic species differs in its delicate test and some times blunt spine tips.
Beaumontella delicata was first described as Baltisphaeridium delicatum, Wall, new species Plate 1, figures 11-13 ; plate 7, figure 6
Originally Baltisphaeridium, subsequently (and now) Beaumontella?; see also Solisphaeridium (combination not validly published). At the time of the transfer, Below, 1987, questionably included this species in Beaumontella and noted that it may represent acritarchs.
Holotype: Wall, 1965, pl.1, fig.11
Occurrence: Lower Lias (S. angulala to C. turneri Zones), Lyme Regis, Dorset.
Age: Hettangian-Sinemurian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Baltisphaeridium delicatum: [Wall, 1965]:
Diagnosis:
An acritarch species with a delicate, ovoid to globular test bearing 20 to 40 simple, hollow spines of medium length.
Description:
The test wall is very thin and easily folded. Its spines are hollow, mostly straight, and taper from bases 2 to 3 a wide to minutely rounded tips, which may be solid. Individual spines vary between one-fifth and one-half of the maximum test dimension in length. Occasionally the test is broken at one end; this is not a constant feature but is due to the delicate nature of the test wall.
Dimensions:
Test only, 16 X 15 µm to 24 X 17 µm; spines 2.5 to 9 µm: holotype 24 X 16 µm, spines 4 µm. (twenty-five specimens).
Affinities:
This species closely resembles Baltisphaeridium brevispinosum Eisenack var. wenlockensts Downie , 1959, p. 59, from the Silurian Wenlock Shale in England. I n addition to their considerably different geological ages, the Liassic species differs in its delicate test and some times blunt spine tips.