Back
Dioxya villosa
Dioxya villosa Eisenack and Cookson 1960; emend. Morgan 1977
Originally (and now) Dioxya, subsequently Vozzhennikovia.
Stover and Evitt, 1978, and Burger, 1980, transferred this species to Vozzhennikovia Lentin and Williams, 1976. Lentin and Williams, 1981, retained it in Dioxya.
Holotype: Eisenack and Cookson, 1960, pl.2, fig.15; Morgan, 1977, pl.2, fig.6a-b
Locus typicus: Moora Bore, Perth Basin, Australia
Stratum typicum: Albian
Original description: Eisenack and Cookson, 1960, p. 10
Shell broadly fusiform to almost sphaerical, with a truncate apical process surmounded by two short bristles; antapical process inconspicuous, pointed, situated in the mid-line or somewhat laterally. Shell-membrane thin, completely invested with minute spinules.
Emended description: Morgan, 1977, p. 134
Pericyst ambitus ovoidal, apex drawn into a broad, truncate apical horn, antapex drawn into two, short, symmetrically located antapical horns which are unequal in length. Epipericyst slightly larger than hypopericyst. Ambital outline widest in pericingular region. Endocyst ovoidal, with two unequal antapical horns, closely appressed against pericyst except in the vicinity of the apical horn, where a small pericoel is developed. Periphragm bears dense, nontabular, 2-3 Ám, sharp spines, aligned only in two rows delineating the pericingulum. Perisulcus not discernible. Endophragm psilate. Archeopyle standard hexa la, periphragm and endophragm closely appressed in archeopyle region.
Dimensions: 52-60 Ám long and 32-43 Ám broad.
Comments: An intercalary archeopyle is visibly open only along the right side of the operculum on the holotype (Pl. 2, fig. 6) but is fully developed on other specimens.
Affinities:
Morgan, 1977, p. 134: Ovoidal to subpentagonal ambitus, dense, 2-3 Ám, sharp, nontabular spines and normal hexa Ia archaeopyle are characteristic for D. villosa. For detailed comparison see treatment of D. armata.
Originally (and now) Dioxya, subsequently Vozzhennikovia.
Stover and Evitt, 1978, and Burger, 1980, transferred this species to Vozzhennikovia Lentin and Williams, 1976. Lentin and Williams, 1981, retained it in Dioxya.
Holotype: Eisenack and Cookson, 1960, pl.2, fig.15; Morgan, 1977, pl.2, fig.6a-b
Locus typicus: Moora Bore, Perth Basin, Australia
Stratum typicum: Albian
Original description: Eisenack and Cookson, 1960, p. 10
Shell broadly fusiform to almost sphaerical, with a truncate apical process surmounded by two short bristles; antapical process inconspicuous, pointed, situated in the mid-line or somewhat laterally. Shell-membrane thin, completely invested with minute spinules.
Emended description: Morgan, 1977, p. 134
Pericyst ambitus ovoidal, apex drawn into a broad, truncate apical horn, antapex drawn into two, short, symmetrically located antapical horns which are unequal in length. Epipericyst slightly larger than hypopericyst. Ambital outline widest in pericingular region. Endocyst ovoidal, with two unequal antapical horns, closely appressed against pericyst except in the vicinity of the apical horn, where a small pericoel is developed. Periphragm bears dense, nontabular, 2-3 Ám, sharp spines, aligned only in two rows delineating the pericingulum. Perisulcus not discernible. Endophragm psilate. Archeopyle standard hexa la, periphragm and endophragm closely appressed in archeopyle region.
Dimensions: 52-60 Ám long and 32-43 Ám broad.
Comments: An intercalary archeopyle is visibly open only along the right side of the operculum on the holotype (Pl. 2, fig. 6) but is fully developed on other specimens.
Affinities:
Morgan, 1977, p. 134: Ovoidal to subpentagonal ambitus, dense, 2-3 Ám, sharp, nontabular spines and normal hexa Ia archaeopyle are characteristic for D. villosa. For detailed comparison see treatment of D. armata.