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Membranilarnacia angustivela
From Fensome et al., 2019:
Membranilarnacia angustivela (Deflandre and Cookson, 1955, p.290, pl.7, figs.4–5) McMinn, 1988, p.150. Holotype: Deflandre and Cookson, 1955, pl.7, fig.4; McMinn, 1988, fig.8C. Originally Membranilarnax, subsequently Samlandia, thirdly (and now) Membranilarnacia. Taxonomic junior synonym: Samlandia solida (name not validly published), according to May (1980, p.24) — however, see discussion under Samlandia solida. Age: Eocene.
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Locus typicus: Birregurra bore No. 1, Victoria, Australia
Stratum typicum: Eocene
Original diagnosis: Deflandre and Cookson, 1955, p.290: Membranilarnax angustivela
Shell ellipsoidal or almost globular, with a rather thick membrane enveloped in a 2nd delicate membrane that is supported by short processes. These processes are either simple or more often grouped so as to form twisted lamellae which have a worm-like appearance in surface view. External outline irregularly wavy.
Dimensions: Holotype: shell 54 by 41 µm, overall 67 by 54 µm, height c. 5 µm. Range: shell alone 41-59 µm, overall diameter 51-72 µm.
Affinities (annotated):
Deflandre and Cookson, 1955, p.290: Membranilarnax angustivela
This species . . . differs very clearly from the known species, particularly in the short distance that separates the outer veil from the true shell membrane.
Membranilarnacia angustivela (Deflandre and Cookson, 1955, p.290, pl.7, figs.4–5) McMinn, 1988, p.150. Holotype: Deflandre and Cookson, 1955, pl.7, fig.4; McMinn, 1988, fig.8C. Originally Membranilarnax, subsequently Samlandia, thirdly (and now) Membranilarnacia. Taxonomic junior synonym: Samlandia solida (name not validly published), according to May (1980, p.24) — however, see discussion under Samlandia solida. Age: Eocene.
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Locus typicus: Birregurra bore No. 1, Victoria, Australia
Stratum typicum: Eocene
Original diagnosis: Deflandre and Cookson, 1955, p.290: Membranilarnax angustivela
Shell ellipsoidal or almost globular, with a rather thick membrane enveloped in a 2nd delicate membrane that is supported by short processes. These processes are either simple or more often grouped so as to form twisted lamellae which have a worm-like appearance in surface view. External outline irregularly wavy.
Dimensions: Holotype: shell 54 by 41 µm, overall 67 by 54 µm, height c. 5 µm. Range: shell alone 41-59 µm, overall diameter 51-72 µm.
Affinities (annotated):
Deflandre and Cookson, 1955, p.290: Membranilarnax angustivela
This species . . . differs very clearly from the known species, particularly in the short distance that separates the outer veil from the true shell membrane.