Back
Hemiplacophora semilunifera
Hemiplacophora semilunifera Cookson and Eisenack, 1965, p.126
Holotype: Cookson and Eisenack, 1965, pl.14, fig.4-5
Paratypes: Cookson and Eisenack, 1965
Locus typicus: Browns Creek Clays, SW Victoria, Australia
Stratum typicum: Late Eocene
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hemiplacophora semilunifera Cookson and Eisenack, 1965a. Gonyaulacaceae, subfamily uncertain. This species has soleate ridges, which on the pre- and postcingular plates are open towards the cingulum and have migrated towards the apical and antapical poles respectively. The wall is finely granulate. The archeopyle is apical. Schematophora speciosa differs in having annulate ridges on each plate. Size: overall length 60-70 µm, width 56-62 µm.
--------------------------------------------------
Original description: Cookson and Eisenack 1965, p. 126
Shell small, broadly oval with slightly flattened apex and antapex, in one specimen five typical fields have been seen in the "epitheca" and four or five in the "hypotheca". Ledges of the ventral surface usually low, not enclosing fields, very variable as to shape and length, occasionally almost circular outline. The wing-like expansions of the ledges are variable in width, height, and degree of perforation; they are frequently inconspicuous on the ventral surface. Wall of shell relatively thick, closely and finely granular. The operculum bears two approx. circular ledges and two short straight ones.
Dimensions: holotype over all length c. 60-70 µm, overall width c. 57 µm; shell c. 54x50 µm. Range overall length c. 60-70 µm, overall width c. 56-62 µm.
Holotype: Cookson and Eisenack, 1965, pl.14, fig.4-5
Paratypes: Cookson and Eisenack, 1965
Locus typicus: Browns Creek Clays, SW Victoria, Australia
Stratum typicum: Late Eocene
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hemiplacophora semilunifera Cookson and Eisenack, 1965a. Gonyaulacaceae, subfamily uncertain. This species has soleate ridges, which on the pre- and postcingular plates are open towards the cingulum and have migrated towards the apical and antapical poles respectively. The wall is finely granulate. The archeopyle is apical. Schematophora speciosa differs in having annulate ridges on each plate. Size: overall length 60-70 µm, width 56-62 µm.
--------------------------------------------------
Original description: Cookson and Eisenack 1965, p. 126
Shell small, broadly oval with slightly flattened apex and antapex, in one specimen five typical fields have been seen in the "epitheca" and four or five in the "hypotheca". Ledges of the ventral surface usually low, not enclosing fields, very variable as to shape and length, occasionally almost circular outline. The wing-like expansions of the ledges are variable in width, height, and degree of perforation; they are frequently inconspicuous on the ventral surface. Wall of shell relatively thick, closely and finely granular. The operculum bears two approx. circular ledges and two short straight ones.
Dimensions: holotype over all length c. 60-70 µm, overall width c. 57 µm; shell c. 54x50 µm. Range overall length c. 60-70 µm, overall width c. 56-62 µm.