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Valensiella clathroderma
Valensiella clathrodermata (Deflandre and Cookson, 1955) Eisenack, 1963
Originally Membranilarnax, subsequently Valensiella, thirdly (and now) Valensiella?.
Tax. sr. synonym of Membranilarnacia densa Cookson and Eisenack, 1974, according to Stover and Evitt, 1978.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Valensiella.
Holotype: Deflandre and Cookson, 1955, pl.7, fig.6; text-fig.51
Locus typicus: Birregurra, Victoria, bore No. 1, at 842 - 843 ft.
Stratum typicum: ?Early Eocene
Original diagnosis: Deflandre and Cookson, 1955, p.290: Membranilanax clathrodermata
Shell practically spherical with an angular outline and thin wall surrounded by a 2nd very fine membrane that is indistinctly punctate and perforated with relatively large rounded holes. External membrane attached to the shell, not by individual processes but by membranous lamellae, which form a kind of wide-meshed reticulate surface design wholly independent of the above mentioned holes. External outline irregularly rounded, not exactly concentric with the shell.
Dimensions: Diameter of shell 34 µm, overall diameter 46 µm.
Affinities:
Deflandre and Cookson, 1955, p.290: Membranilanax clathrodermata
At first sight this species seems to closely resemble Membranilarnax cf. liradiscoides from a Senonian flint of the Paris basin, the species having much the same dimensions, but direct comparison of the two specimens shows important differences The external membrane of the Senonian specimen is not clathrate, the trabeculae which attach it to the shell are thicker and more closely arranged and above all, their insertion on the shell is more strongly marked. However, the two forms are clearly closely related.
Originally Membranilarnax, subsequently Valensiella, thirdly (and now) Valensiella?.
Tax. sr. synonym of Membranilarnacia densa Cookson and Eisenack, 1974, according to Stover and Evitt, 1978.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Valensiella.
Holotype: Deflandre and Cookson, 1955, pl.7, fig.6; text-fig.51
Locus typicus: Birregurra, Victoria, bore No. 1, at 842 - 843 ft.
Stratum typicum: ?Early Eocene
Original diagnosis: Deflandre and Cookson, 1955, p.290: Membranilanax clathrodermata
Shell practically spherical with an angular outline and thin wall surrounded by a 2nd very fine membrane that is indistinctly punctate and perforated with relatively large rounded holes. External membrane attached to the shell, not by individual processes but by membranous lamellae, which form a kind of wide-meshed reticulate surface design wholly independent of the above mentioned holes. External outline irregularly rounded, not exactly concentric with the shell.
Dimensions: Diameter of shell 34 µm, overall diameter 46 µm.
Affinities:
Deflandre and Cookson, 1955, p.290: Membranilanax clathrodermata
At first sight this species seems to closely resemble Membranilarnax cf. liradiscoides from a Senonian flint of the Paris basin, the species having much the same dimensions, but direct comparison of the two specimens shows important differences The external membrane of the Senonian specimen is not clathrate, the trabeculae which attach it to the shell are thicker and more closely arranged and above all, their insertion on the shell is more strongly marked. However, the two forms are clearly closely related.