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Polystephanephorus urnaformis
Polystephanephorus urnaformis (Cookson, 1953) Downie and Sarjeant, 1965
Now Emmetrocysta. Originally Cannosphaeropsis, subsequently Polystephanephorus, thirdly (and now) Emmetrocysta. The transfer of this species to Polystephanephorus by Sarjeant, 1961 was effected under the International Code of Zoological Nomenclature and therefore was validly published.
Holotype: Cookson, 1953, pl. 2, fig. 41-42
Locus typicus: Victoria, Anglesea, Australia
Stratum typicum: Oligocene
Original description: Cookson, 1953, p. 118: Cannosphaeropsis urnaformis
Diagnosis: The type specimen of Cannosphaeropsis urnaformis is a smooth ovoid shell 44 x 55 µm with approximately twelve short, broad radially arranged vase-shaped appendages. The latter measure about 20 µm across the base and about 30 µm across the rim and are 15-18 µm long. The walls of the appendages are much perforated, the holes frequently extending from the rim to the prominent annular thickening present at the point of junction of an appendage with the shell-membrane. The rim is entire and slightly fluted. The appendages of this specimen are free from one another. A second example, however, suggests that they may not have always been so, since two of its appendages are definitely attached to one another by a short and delicate strand. The surface of the shell is finely granular.
Now Emmetrocysta. Originally Cannosphaeropsis, subsequently Polystephanephorus, thirdly (and now) Emmetrocysta. The transfer of this species to Polystephanephorus by Sarjeant, 1961 was effected under the International Code of Zoological Nomenclature and therefore was validly published.
Holotype: Cookson, 1953, pl. 2, fig. 41-42
Locus typicus: Victoria, Anglesea, Australia
Stratum typicum: Oligocene
Original description: Cookson, 1953, p. 118: Cannosphaeropsis urnaformis
Diagnosis: The type specimen of Cannosphaeropsis urnaformis is a smooth ovoid shell 44 x 55 µm with approximately twelve short, broad radially arranged vase-shaped appendages. The latter measure about 20 µm across the base and about 30 µm across the rim and are 15-18 µm long. The walls of the appendages are much perforated, the holes frequently extending from the rim to the prominent annular thickening present at the point of junction of an appendage with the shell-membrane. The rim is entire and slightly fluted. The appendages of this specimen are free from one another. A second example, however, suggests that they may not have always been so, since two of its appendages are definitely attached to one another by a short and delicate strand. The surface of the shell is finely granular.