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Meiourogonyaulax maculata
Meiourogonyaulax maculata Backhouse, 1988, p.96
Originally (and now) Meiourogonyaulax, subsequently Lithodinia. This species is here retained in Meiourogonyaulax following the retention of the genus by Riding and Helby (2001d, p.81,83).
Holotype: Backhouse, 1988, pl.32, figs.9a-b text-figs. 29A-B
Locus typicus: Perth Basin, W Australia
Stratum typicum: Early Barremian
Original description: Backhouse, 1988, p.96
Small to medium proxlmate cyst, ovoid to lenticular, compressed laterally. Autophragm, less than 0.5 µm thick, usually entirely covered with small round dark grana of no descernible height, up to 1 µm in basal diameter; grana imparting a spotted appearance to the cyst. Some populations lack visible grana. Paracingulum approximately 5 µm wide, clearly expressed by low (less than 1 µm) narrow septa, offset 2 paracingulum widths. Details of parasulcus not usually observed because of lateral compression. Paratabulation on remainder of cyst weakly expressed by low septa; formula: ?4", 6"", Xc, 6""", 1p, 1"""". Archeopyle apical, type [tA], operculum free. Operculum bears a small truncate apical spine, 2 µm long.
Dimensions: Length of holotype without operculum 50 µm, width 51 µm. Range of length without operculum (31 specimens) 33(43)52 µm, width 41(40)60 mm. Length of one complete specimen 57 µm.
Affinities:
Backhouse, 1988, p.96: The spotted appearance, thin autophragm, and lateral compression distinguish if Meiourogonyaulax maculata from other species of the genus.
Originally (and now) Meiourogonyaulax, subsequently Lithodinia. This species is here retained in Meiourogonyaulax following the retention of the genus by Riding and Helby (2001d, p.81,83).
Holotype: Backhouse, 1988, pl.32, figs.9a-b text-figs. 29A-B
Locus typicus: Perth Basin, W Australia
Stratum typicum: Early Barremian
Original description: Backhouse, 1988, p.96
Small to medium proxlmate cyst, ovoid to lenticular, compressed laterally. Autophragm, less than 0.5 µm thick, usually entirely covered with small round dark grana of no descernible height, up to 1 µm in basal diameter; grana imparting a spotted appearance to the cyst. Some populations lack visible grana. Paracingulum approximately 5 µm wide, clearly expressed by low (less than 1 µm) narrow septa, offset 2 paracingulum widths. Details of parasulcus not usually observed because of lateral compression. Paratabulation on remainder of cyst weakly expressed by low septa; formula: ?4", 6"", Xc, 6""", 1p, 1"""". Archeopyle apical, type [tA], operculum free. Operculum bears a small truncate apical spine, 2 µm long.
Dimensions: Length of holotype without operculum 50 µm, width 51 µm. Range of length without operculum (31 specimens) 33(43)52 µm, width 41(40)60 mm. Length of one complete specimen 57 µm.
Affinities:
Backhouse, 1988, p.96: The spotted appearance, thin autophragm, and lateral compression distinguish if Meiourogonyaulax maculata from other species of the genus.