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Occisucysta mazaganensis
Occisucysta mazaganensis Below, 1984
Now Tehamadinium. Originally Occisucysta, subsequently (and now) Tehamadinium.
Holotype: Below, 1984, pl.7, figs.1A-B; Jan du Chêne et al., 1986(a), pl.117, figs.4-6; Jan du Chêne et al., 1986(b), pl.21, figs.1-9
Locus typicus: Mazagan Plateau, off NW Africa
Stratum typicum: Late Albian
Original diagnosis: Below, 1984, p.636
Large, proximate, spheroidal, two-layered, acavate or cornucavate cyst with a low apical bulge. Endophragma smooth, periphragma reticulated, bearing solid, irregularly interconnected spines that are strung together on parasutures. Paratabulation goniaulacacean ?XPR, 4", 6"", Xc, as, rs, Is, ps, pv, 6""", 1"""", with torsion of hypocyst against epicyst so that the 3"""/4""" paraplate boundary is mid-dorsal. One or two additional, isolated, solid spines per paraplate. Archeopyle type 2P[2""-3""].
Dimensions. Holotype: length 86 µm, breadth 72 µm, length of spines 6 µm to 10 µm; other specimens: length 78-95 µm, breadth 68-81 µm, length of spines 2-12 µm.
Original description: Below, 1984, p.636-637
The large, two-layered cyst has an overall oval to subspheroidal ambitus. It tapers apically, forming an apical horn or a low, apical bulge. The smooth endophragma and the reticulated periphragma are attached. Only in a few cases do they form a cornucavatepericoel in the apical region. The cyst wall gives rise to solid acuminate spines of varying height and width, which are arranged on parasutures. Spines are irregularly connected at different heights (Fig. 7). Generally, there are one or two solid, acuminate intratabular spines in the center of most paraplates. A goniaulacacean paratabulation is defined: ?XPR, 4", 6"", Xc, as, rs, Is, ps, pv, 6""", 1"""". The preapical plates are difficult to distinguish because the apical horn builds a complicated trestle, formed by the junctions of the parasutural spine-rows between apical paraplates. Nevertheless, the crownlike morphology of the apical horn tip implies the existence of such preapical paraplates. The apical series is comprised of a narrow, long 1", pentagonal 2" and 3" and a rhombic 4". Paraplate 4" fills the angle between 5"" and 6"", as is typical for the species of the genus Occisucysta. The paraplates of the precingular series are trapezoidal or pentagonal and equally large, except for the smaller pentagonal 6"". The equatorially situated paracingulum is offset by its width at the parasulcus. In contrast to other paraplates, the paracingulum bottom is built up of a very coarse periphragmal net. The postcingular series begins with a small rectangular 1""" and continues with the equilateral triangular 2""" and trapezoidal 3""" to 6""". The pv plate is elongate and polygonal. In the parasulcus, it is possible to observe the anterior/posteriorly elongated rs and Is and an arched ps. The trapezoidal 1"""" is indented by this ps paraplate. Epicyst and hypocyst series are distorted so that the 3"""/4""" boundary is mid-dorsal. Archeopyle type 2P[2""-3""].
Affinities:
Below, 1984, p.637: The irregularly connected rows of parasutural spines, which look like a crown of thorns, are typical for this species, which resembles only Occisucysta paucispina (Eisenack and Cookson, 1960) Below, 1981. This species has few parasutural spines which are not connected or are only basally interconnected.
Now Tehamadinium. Originally Occisucysta, subsequently (and now) Tehamadinium.
Holotype: Below, 1984, pl.7, figs.1A-B; Jan du Chêne et al., 1986(a), pl.117, figs.4-6; Jan du Chêne et al., 1986(b), pl.21, figs.1-9
Locus typicus: Mazagan Plateau, off NW Africa
Stratum typicum: Late Albian
Original diagnosis: Below, 1984, p.636
Large, proximate, spheroidal, two-layered, acavate or cornucavate cyst with a low apical bulge. Endophragma smooth, periphragma reticulated, bearing solid, irregularly interconnected spines that are strung together on parasutures. Paratabulation goniaulacacean ?XPR, 4", 6"", Xc, as, rs, Is, ps, pv, 6""", 1"""", with torsion of hypocyst against epicyst so that the 3"""/4""" paraplate boundary is mid-dorsal. One or two additional, isolated, solid spines per paraplate. Archeopyle type 2P[2""-3""].
Dimensions. Holotype: length 86 µm, breadth 72 µm, length of spines 6 µm to 10 µm; other specimens: length 78-95 µm, breadth 68-81 µm, length of spines 2-12 µm.
Original description: Below, 1984, p.636-637
The large, two-layered cyst has an overall oval to subspheroidal ambitus. It tapers apically, forming an apical horn or a low, apical bulge. The smooth endophragma and the reticulated periphragma are attached. Only in a few cases do they form a cornucavatepericoel in the apical region. The cyst wall gives rise to solid acuminate spines of varying height and width, which are arranged on parasutures. Spines are irregularly connected at different heights (Fig. 7). Generally, there are one or two solid, acuminate intratabular spines in the center of most paraplates. A goniaulacacean paratabulation is defined: ?XPR, 4", 6"", Xc, as, rs, Is, ps, pv, 6""", 1"""". The preapical plates are difficult to distinguish because the apical horn builds a complicated trestle, formed by the junctions of the parasutural spine-rows between apical paraplates. Nevertheless, the crownlike morphology of the apical horn tip implies the existence of such preapical paraplates. The apical series is comprised of a narrow, long 1", pentagonal 2" and 3" and a rhombic 4". Paraplate 4" fills the angle between 5"" and 6"", as is typical for the species of the genus Occisucysta. The paraplates of the precingular series are trapezoidal or pentagonal and equally large, except for the smaller pentagonal 6"". The equatorially situated paracingulum is offset by its width at the parasulcus. In contrast to other paraplates, the paracingulum bottom is built up of a very coarse periphragmal net. The postcingular series begins with a small rectangular 1""" and continues with the equilateral triangular 2""" and trapezoidal 3""" to 6""". The pv plate is elongate and polygonal. In the parasulcus, it is possible to observe the anterior/posteriorly elongated rs and Is and an arched ps. The trapezoidal 1"""" is indented by this ps paraplate. Epicyst and hypocyst series are distorted so that the 3"""/4""" boundary is mid-dorsal. Archeopyle type 2P[2""-3""].
Affinities:
Below, 1984, p.637: The irregularly connected rows of parasutural spines, which look like a crown of thorns, are typical for this species, which resembles only Occisucysta paucispina (Eisenack and Cookson, 1960) Below, 1981. This species has few parasutural spines which are not connected or are only basally interconnected.