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Tehamadinium sousense
Tehamadinium sousense (Below, 1981) Jan du Chêne et al. in Jan du Chêne et al., 1986a; emend. Jan du Chêne et al., 1986b
Originally Occisucysta, subsequently (and now) Tehamadinium.
This combination was not validly published in Jan du Chêne et al. (1986a, p.352), since the generic name Tehamadinium was not validly published.
Holotype: Below, 1981, pl.8, figs.1a-b; Jan du Chêne et al., 1986a, pl.117, figs.7-10; Jan du Chene et al., 1986b, pl.22, figs.1-5
Locus typicus: Ravine northwest of Amalou, southwest Morocco
Stratum typicum: Aptian: Gargasian
Translation Below, 1981: Fensome, 1991, p. 744-745
Translation Jan du Chêne et al., 1986: Fensome et al., 1991, p. 745-746
Original diagnosis: Below, 1981, p. 62: Occisucysta sousense
Spherical, proximate cyst with a gonyaulacoid tabulation. Epicyst and hypocyst of approximately equal size, separated by a weakly helicoid paracingulum. Parasulcus subdivided. Cyst subdivided into paraplates according to the following scheme: 4", 6"", Xc, 6""", lpc, 1"""", lps. Field boundaries marked by low, arcade-like ridges. Intratabular appendages absent. Endophragm delicate and smooth, periphragm irregularly and finely reticulate. Archeopyle type 2P(2""-3"").
Original description: Below, 1981, p. 62 for Occisucysta sousense
The cyst is usually spheroidal. Rounded pentagonal or rhomboidal forms rarely occur. Changes in outline are common and are due to the instability of the thin-walled body, which results from development of the large precingular archeopyle. I believe that the common tendency of the cyst to break along the anterior paracingular margin can be attributed to the same cause. The epicyst, with its small apical horn which occasionally may be absent, is approximately of the same size as the hypocyst. The paracingulum separating the two halves of the cyst, is equatorial and is offset at the short parasulcus by a distance equal to its own width and is thus only moderately helicoidal. There is a suggestion of individual paraplates; however, it cannot be determined due to extremely weak development of parasutural ridges. Low, perforate ridges, laterally changing irregularly into a reticulum, with smooth, undulate or occasionally weakly spiny crests follow the paraplate boundaries. In some specimens, some of these ridges have been enlarged and constitute high, perforate septa of the type known to occur in Occisucysta tenuiceras (Eisenack 1958) comb. nov. thus indicating the close relationship of the two species. The paratabuiation of both forms is also similar, even in detail so that the description of Occisucysta tenuiceras (Eisenack 1958) comb. nov. ([Below, 1981a] p.63) can be referred to.
Intratabular ornamentation is usually absent. The surface consists of an even, irregularly perforated periphragm which is superimposed on a smooth endophragm. Occasional intratabular spines are only rarely developed.
Emended diagnosis: Jan du Chêne et al., 1986, p. 28 for Tehamadinium sousense
Proximate, subspherical to slightly ovoidal dinoflagellate cyst with paratabulation of the gonyaulacoid type lpr, 4", 6"", 6c, 5s, 6""", lp, 1"""". The autophragm is thick and vacuolate. The cyst is surmounted by a slight apical protuberance. The parasutural septa are irregularly and finely fenestrate. Their crests are adorned with short, well spaced spines with pointed distal extremities. The intratabular areas are adorned with occasional, irregularly arranged spines, which occur especially on the precingular, postcingular and antapical paraplates. The precingular archeopyle is of type 2P (2" + 3"). Operculum compound, free.
Emended description: Jan du Chêne et al., 1986, p. 28 for Tehamadinium sousense
Proximate, subspherical to slightly ovoidal dinoflagellate cyst with paratabulation of the gonyaulacoid type lpr, 4", 6", 6c, 5s, 6""", lp, 1"""". The autophragm is thick and vacuolate. The cyst is surmounted by a slight apical protuberance. The parasutural septa are always well developed, even those delimiting cingular and sulcal paraplates. These parasutural septa are fine, irregularly and finely fenestrate. Their crests are adorned with short and fine, well spaced spines, pointed distally. The intratabular areas are densely punctate, the punctation being due to the vacuolate structure of the autophragm. Some irregularly arranged spines may ornament the precingular and postcingular paraplates. These spines seem more abundant on the antapical paraplate. The parasutural septa marking the anterior margin of the cingulum at the contact of the opening (2" + 3") are generally absent where the opercular plates are detached, whereas the parasutural septa delimiting the anterior margin of the opening are preserved. The paracingulum is composed of six plates. It is weakly sinistrally spiral.
Originally Occisucysta, subsequently (and now) Tehamadinium.
This combination was not validly published in Jan du Chêne et al. (1986a, p.352), since the generic name Tehamadinium was not validly published.
Holotype: Below, 1981, pl.8, figs.1a-b; Jan du Chêne et al., 1986a, pl.117, figs.7-10; Jan du Chene et al., 1986b, pl.22, figs.1-5
Locus typicus: Ravine northwest of Amalou, southwest Morocco
Stratum typicum: Aptian: Gargasian
Translation Below, 1981: Fensome, 1991, p. 744-745
Translation Jan du Chêne et al., 1986: Fensome et al., 1991, p. 745-746
Original diagnosis: Below, 1981, p. 62: Occisucysta sousense
Spherical, proximate cyst with a gonyaulacoid tabulation. Epicyst and hypocyst of approximately equal size, separated by a weakly helicoid paracingulum. Parasulcus subdivided. Cyst subdivided into paraplates according to the following scheme: 4", 6"", Xc, 6""", lpc, 1"""", lps. Field boundaries marked by low, arcade-like ridges. Intratabular appendages absent. Endophragm delicate and smooth, periphragm irregularly and finely reticulate. Archeopyle type 2P(2""-3"").
Original description: Below, 1981, p. 62 for Occisucysta sousense
The cyst is usually spheroidal. Rounded pentagonal or rhomboidal forms rarely occur. Changes in outline are common and are due to the instability of the thin-walled body, which results from development of the large precingular archeopyle. I believe that the common tendency of the cyst to break along the anterior paracingular margin can be attributed to the same cause. The epicyst, with its small apical horn which occasionally may be absent, is approximately of the same size as the hypocyst. The paracingulum separating the two halves of the cyst, is equatorial and is offset at the short parasulcus by a distance equal to its own width and is thus only moderately helicoidal. There is a suggestion of individual paraplates; however, it cannot be determined due to extremely weak development of parasutural ridges. Low, perforate ridges, laterally changing irregularly into a reticulum, with smooth, undulate or occasionally weakly spiny crests follow the paraplate boundaries. In some specimens, some of these ridges have been enlarged and constitute high, perforate septa of the type known to occur in Occisucysta tenuiceras (Eisenack 1958) comb. nov. thus indicating the close relationship of the two species. The paratabuiation of both forms is also similar, even in detail so that the description of Occisucysta tenuiceras (Eisenack 1958) comb. nov. ([Below, 1981a] p.63) can be referred to.
Intratabular ornamentation is usually absent. The surface consists of an even, irregularly perforated periphragm which is superimposed on a smooth endophragm. Occasional intratabular spines are only rarely developed.
Emended diagnosis: Jan du Chêne et al., 1986, p. 28 for Tehamadinium sousense
Proximate, subspherical to slightly ovoidal dinoflagellate cyst with paratabulation of the gonyaulacoid type lpr, 4", 6"", 6c, 5s, 6""", lp, 1"""". The autophragm is thick and vacuolate. The cyst is surmounted by a slight apical protuberance. The parasutural septa are irregularly and finely fenestrate. Their crests are adorned with short, well spaced spines with pointed distal extremities. The intratabular areas are adorned with occasional, irregularly arranged spines, which occur especially on the precingular, postcingular and antapical paraplates. The precingular archeopyle is of type 2P (2" + 3"). Operculum compound, free.
Emended description: Jan du Chêne et al., 1986, p. 28 for Tehamadinium sousense
Proximate, subspherical to slightly ovoidal dinoflagellate cyst with paratabulation of the gonyaulacoid type lpr, 4", 6", 6c, 5s, 6""", lp, 1"""". The autophragm is thick and vacuolate. The cyst is surmounted by a slight apical protuberance. The parasutural septa are always well developed, even those delimiting cingular and sulcal paraplates. These parasutural septa are fine, irregularly and finely fenestrate. Their crests are adorned with short and fine, well spaced spines, pointed distally. The intratabular areas are densely punctate, the punctation being due to the vacuolate structure of the autophragm. Some irregularly arranged spines may ornament the precingular and postcingular paraplates. These spines seem more abundant on the antapical paraplate. The parasutural septa marking the anterior margin of the cingulum at the contact of the opening (2" + 3") are generally absent where the opercular plates are detached, whereas the parasutural septa delimiting the anterior margin of the opening are preserved. The paracingulum is composed of six plates. It is weakly sinistrally spiral.