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Membranilarnacia angustivela
Membranilarnacia angustivela (Deflandre and Cookson, 1955) McMinn, 1988
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.
Holotype: Deflandre and Cookson, 1955, pl.7, fig.4; McMinn, 1988, fig.8C
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 Ám, overall 67 by 54 Ám, height c. 5 Ám. Range: shell alone 41-59 Ám, overall diameter 51-72 Ám.
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.
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.
Holotype: Deflandre and Cookson, 1955, pl.7, fig.4; McMinn, 1988, fig.8C
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 Ám, overall 67 by 54 Ám, height c. 5 Ám. Range: shell alone 41-59 Ám, overall diameter 51-72 Ám.
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.