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Maghrebinia perforata ssp. mirabilis
Maghrebinia perforata ssp. mirabilis Below, 1984; Emendation: Masure, 1988a, p.366–368, as Maghrebinia mirabilis.
NOW Montanarocysta mirabilis. Originally Maghrebinia perforata subsp. mirabilis, subsequently Maghrebinia mirabilis, thirdly Atopodinium mirabile, fourthly (and now) Montanarocysta mirabilis.
Holotype: Below, 1981a, pl.1, figs.1a–c, as Maghrebinia perforata; Masure, 1988a, pl.3, figs.1–11; text-figs.4a–c; Fauconnier and Masure, 2004, pl.10, figs.1–4.
Locus typicus: Section Ida ou Tanane in the north of Agadir, Morocco
Stratum typicum: Late Albian-Early Cenomanian
Original diagnosis: Below, 1984, p. 635
Chorate, somewhat lenticular cyst with bitrapezoidal size. Divided into a small epicyst and a greater hypocyst by an equatorial planispiral intratabular membrane. Paraplates bordered by high, distally denticulated, perforated or unperforated membranes, which are often irregularly and deeply slit. An apical area with few intratabular processes as well as the antapical, four precingular, and three postcingular paraplates are bordered by these septa. Nevertheless, the paraplate scheme could be 3"-?4", 5"", 0c, 4""", 1"""" because the large ventral area between polar plates is undifferentiated. The right end of the paracingulum extends into this area. The cyst surface is microfrangate (see Below, 1981, p. 23). Endophragmal gonal membranal thickening is often perforated. Archeopyle type [A].
Dimensions. Holotype: length 80 µm; paratypes: length 62-96 µm, breadth 60-90 µm.
Affinities:
Below, 1984, p.636: The subspecies Maghrebinia perforata (Clarke and Verdier, 1967) Below, 1981 ssp. mirabilis n.ssp. differs from M. perforata (Clarke and Verdier, 1967) Below, 1981 ssp. perforata by its coarse and deep, irregular splitting of the high parasutural membranes. Septures of the letter subspecies are lower, are nearly constant in height, and are finely distally denticulated.
Two types of parasutural septa variations are now known: (1) the successive reduction of membrane height from M. perforata ssp. mirabilis to M. perforata ssp. perforata; (2) the second type is the interruption of membranes by deep splits and consequently the total absence of membranes between gonal thickenings, as occurs in the range of variation between M. perforata ssp. mirabilis and M. chleuh Below, 1981.
NOW Montanarocysta mirabilis. Originally Maghrebinia perforata subsp. mirabilis, subsequently Maghrebinia mirabilis, thirdly Atopodinium mirabile, fourthly (and now) Montanarocysta mirabilis.
Holotype: Below, 1981a, pl.1, figs.1a–c, as Maghrebinia perforata; Masure, 1988a, pl.3, figs.1–11; text-figs.4a–c; Fauconnier and Masure, 2004, pl.10, figs.1–4.
Locus typicus: Section Ida ou Tanane in the north of Agadir, Morocco
Stratum typicum: Late Albian-Early Cenomanian
Original diagnosis: Below, 1984, p. 635
Chorate, somewhat lenticular cyst with bitrapezoidal size. Divided into a small epicyst and a greater hypocyst by an equatorial planispiral intratabular membrane. Paraplates bordered by high, distally denticulated, perforated or unperforated membranes, which are often irregularly and deeply slit. An apical area with few intratabular processes as well as the antapical, four precingular, and three postcingular paraplates are bordered by these septa. Nevertheless, the paraplate scheme could be 3"-?4", 5"", 0c, 4""", 1"""" because the large ventral area between polar plates is undifferentiated. The right end of the paracingulum extends into this area. The cyst surface is microfrangate (see Below, 1981, p. 23). Endophragmal gonal membranal thickening is often perforated. Archeopyle type [A].
Dimensions. Holotype: length 80 µm; paratypes: length 62-96 µm, breadth 60-90 µm.
Affinities:
Below, 1984, p.636: The subspecies Maghrebinia perforata (Clarke and Verdier, 1967) Below, 1981 ssp. mirabilis n.ssp. differs from M. perforata (Clarke and Verdier, 1967) Below, 1981 ssp. perforata by its coarse and deep, irregular splitting of the high parasutural membranes. Septures of the letter subspecies are lower, are nearly constant in height, and are finely distally denticulated.
Two types of parasutural septa variations are now known: (1) the successive reduction of membrane height from M. perforata ssp. mirabilis to M. perforata ssp. perforata; (2) the second type is the interruption of membranes by deep splits and consequently the total absence of membranes between gonal thickenings, as occurs in the range of variation between M. perforata ssp. mirabilis and M. chleuh Below, 1981.