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Pyxidiella scrobiculata
Pyxidiella? scrobiculata (Deflandre and Cookson, 1955) Cookson and Eisenack, 1958
Originally Leiosphaera (an acritarch genus), subsequently Pyxidiella, thirdly Leiosphaeridia (an acritarch genus), fourthly Palaeostomocystis, fifthly (and now) Pyxidiella?, sixthly Batiacasphaera. Stover and Evitt, 1978 considered this to be a "provisionally accepted species" of Pyxidiella. Burger, 1980 transferred this species to Batiacasphaera Drugg, 1970; however, de Coninck, 1986 questionably retained it in Pyxidiella.
Holotype: Deflandre and Cookson, 1955, pl.3, fig.3
Locus typicus: W. A., Perth Basin, Gingin
Stratum typicum: Senonian-Eocene
Original diagnosis: Cookson and Eisenack, 19558, p.291: Leiosphaera scrobiculata
Shell ovoidal or ellipsoidal, generally with an irregular polygonal opening at the narrower end, the cover of which is sometimes in position. Wall of shell about 3-5 µm thick, finely punctate, and closely dotted with irregular scrobiculi.
Dimensions: Cretaceous examples: 61-94 µm long, 48-72 µm broad. Tertiary examples: 38-54 µm long, 31-41 µm broad.
Comments: Cookson and Eisenack 1958, p. 52
The Upper Cretaceous and Tertiary shells described by Deflandre and Cookson (1955) appear to be related to Pyxidiella. For this reason they have been removed from Leiosphaera (Eisenack 1938), a genus which we think should be used, as originally intended, for spherical forms only.
Originally Leiosphaera (an acritarch genus), subsequently Pyxidiella, thirdly Leiosphaeridia (an acritarch genus), fourthly Palaeostomocystis, fifthly (and now) Pyxidiella?, sixthly Batiacasphaera. Stover and Evitt, 1978 considered this to be a "provisionally accepted species" of Pyxidiella. Burger, 1980 transferred this species to Batiacasphaera Drugg, 1970; however, de Coninck, 1986 questionably retained it in Pyxidiella.
Holotype: Deflandre and Cookson, 1955, pl.3, fig.3
Locus typicus: W. A., Perth Basin, Gingin
Stratum typicum: Senonian-Eocene
Original diagnosis: Cookson and Eisenack, 19558, p.291: Leiosphaera scrobiculata
Shell ovoidal or ellipsoidal, generally with an irregular polygonal opening at the narrower end, the cover of which is sometimes in position. Wall of shell about 3-5 µm thick, finely punctate, and closely dotted with irregular scrobiculi.
Dimensions: Cretaceous examples: 61-94 µm long, 48-72 µm broad. Tertiary examples: 38-54 µm long, 31-41 µm broad.
Comments: Cookson and Eisenack 1958, p. 52
The Upper Cretaceous and Tertiary shells described by Deflandre and Cookson (1955) appear to be related to Pyxidiella. For this reason they have been removed from Leiosphaera (Eisenack 1938), a genus which we think should be used, as originally intended, for spherical forms only.