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Maghrebinia chleuh
Maghrebinia chleuh Below, 1981; emend. Masure, 1988
NOW Montanarocysta. Originally Maghrebinia, subsequently Atopodinium, thirdly (and now) Montanarocysta.
Holotype: Below, 1981a, pl.1, figs.5a–b; text-figs.13a–b; Masure, 1988a, pl.2, figs.1–8; text-figs.3a–b; Fensome et al., 1991, figs.1–4 — p.619; Fauconnier and Masure, 2004, pl.9, figs.1–3.
Paratypes: Below, 1981
Locus typicus: Imi Quadder, Morocco
Stratum typicum: Vraconian-Cenomanian
Translations Below, 1981 and Masure, 1988: LPP
Original description: Below, 1981, p. 22-23
Diagnosis: Chorate, bilayered cyst, consisting of, in outline, semispherical epicyst and slightly larger trapezoidal to nearly trigonal hypocyst. Periphragm and endophragm smooth to psilate. Parasutures bear isolated or sometimes proximally partially interconnected, perforate, distally polyfurcate processes. Along with four apicals, several precingulars and postcingulars, an antapical paraplate is fixed in this way. They are arranged as in Maghrebinia perforata (Clarke and Verdier, 1967) Below, 1981. Equatorially arranged processes of similar construction mark the spiral paracingulum. A very wide, undifferentiated parasulcal zone is developed ventrally. An archaeopyle was not observed. the surface is smooth to psilate.
Description (annotated): Striking characteristic of the new species are the processes, arranged on the on the parasutures and paracingulum, consisting of coarsely perforated endophragm, standing on the smooth periphragm. They stand isolated gonally or they are proximally partially interconnected by low membranes. Hollow or solid at the bases, round or taeniate in cross section, they broaden distally and terminate unbranched with concave, convex or straight, finely denticulate margin, or are first and second order furcate. The processes correspond to the reinforcement band in the straight parasutural membranes in Magrebinia perforata (Clarke and Verdier, 1967) Below, 1981. Both species are thus related. Transitional forms with more or less strongly reduced membranes and numerous, isolated processes are present in the Moroccan material. Both species also correspond in paratabulation. Especially interesting is the apical region of M. chleuh, since because it helps to clarify the paraplate arrangement in M. perforata, which remained unclear due to the variable reduction of the apical processes: around the apex we find four processes. They are all considered remnants of membranes between the four apical paraplates. Posterior to these, a second crown of several (in the holotype 10) processes occurs - the remnants of hollow membranes betweeen precingular and apical paraplates.
An archaeopyle was not observed in any specimeen. Based on the relation to M. perforata, an apical archaeopyle can be expected.
Dimensions: Holotype: Length (without processes) 55 Ám; width (without processes) 48 Ám; processes 12-18 Ám; other specimens: length (without processes) 45-60 Ám (average 53 Ám); width (without processes) 40-54 Ám (average 47 Ám); processes 7-18 Ám. 28 specimens.
Emended description: Masure, 1988, p. 365-366
Diagnosis: Chorate to proximochorate dinoflagellate cyst, acavate, subspherical, in outline rounded polygonal. Wall formed consisting of autophragm or closely appressed endophragm and periphragm, surface smooth to scabrate, granular at the bases of the processes. Paratabulation sexiform gonyaulacoid, indicated by intratabular, penitabular and parasutural processes. Ventral area undifferentiated. Processes granular and perforate, distally free, frequently interconnected proximally. Archaeopyle apical, type (tA)a, with accessory precingular sutures. Operculum composite adnate.
Emended description: Chorate to proximochorate, subspherical cyst, slightly dorsoventrally compressed. The polygonal outline is rounded asymmetrical, the epicystsmaller than the hypocyst. Wall consisting of autophragm or closely appressed endophragm and periphragm. Surface smooth to scabrate, granular at the bases of the processes. The granular and perforate processes, distally free, truncate or ramified, are frequently interconnected proximally. The paratabulation follows the sexiform gonyaulacoid model. According to the distribution of the processes, the apparent paratabulation is formed by 0-?2 preapical(s), 4 apicals, 6 precingulars, X cingulars, 5 postcingulars, ?1 postintercalary, 1 antapical, X sulcals. The sulcal paraplates and the sutures between the sulcus and adjacent paraplates (2, 1i, X, II and IV) are not expressed by reliefs. A preapical process may be present. Four or more processes ornament the apicals. penitabular processes, with adcingular interruptions, border the anterior part of the precingular paraplates. The sagging paracingulum is indicated by intratabular processes. Only the four postcingular parasutures II/III, III/IV, IV/V and V/VI bear processes. The antapical paraplate Y is delimited by parasutural processes; it may bear a bifid process. The apical archaeopyle is of the (tA)a type, with accessory sutures developed between the precingulars. The composite opeculum is adnate.
Affinities:
Masure, 1988, p. 365
Maghrebinia chleuh differs from the other Maghrebinia species in its distally isolated and proximally interconnected processes. According to Below, 1984, transitional forms between M. chleuh and M. mirabilis do exist.
NOW Montanarocysta. Originally Maghrebinia, subsequently Atopodinium, thirdly (and now) Montanarocysta.
Holotype: Below, 1981a, pl.1, figs.5a–b; text-figs.13a–b; Masure, 1988a, pl.2, figs.1–8; text-figs.3a–b; Fensome et al., 1991, figs.1–4 — p.619; Fauconnier and Masure, 2004, pl.9, figs.1–3.
Paratypes: Below, 1981
Locus typicus: Imi Quadder, Morocco
Stratum typicum: Vraconian-Cenomanian
Translations Below, 1981 and Masure, 1988: LPP
Original description: Below, 1981, p. 22-23
Diagnosis: Chorate, bilayered cyst, consisting of, in outline, semispherical epicyst and slightly larger trapezoidal to nearly trigonal hypocyst. Periphragm and endophragm smooth to psilate. Parasutures bear isolated or sometimes proximally partially interconnected, perforate, distally polyfurcate processes. Along with four apicals, several precingulars and postcingulars, an antapical paraplate is fixed in this way. They are arranged as in Maghrebinia perforata (Clarke and Verdier, 1967) Below, 1981. Equatorially arranged processes of similar construction mark the spiral paracingulum. A very wide, undifferentiated parasulcal zone is developed ventrally. An archaeopyle was not observed. the surface is smooth to psilate.
Description (annotated): Striking characteristic of the new species are the processes, arranged on the on the parasutures and paracingulum, consisting of coarsely perforated endophragm, standing on the smooth periphragm. They stand isolated gonally or they are proximally partially interconnected by low membranes. Hollow or solid at the bases, round or taeniate in cross section, they broaden distally and terminate unbranched with concave, convex or straight, finely denticulate margin, or are first and second order furcate. The processes correspond to the reinforcement band in the straight parasutural membranes in Magrebinia perforata (Clarke and Verdier, 1967) Below, 1981. Both species are thus related. Transitional forms with more or less strongly reduced membranes and numerous, isolated processes are present in the Moroccan material. Both species also correspond in paratabulation. Especially interesting is the apical region of M. chleuh, since because it helps to clarify the paraplate arrangement in M. perforata, which remained unclear due to the variable reduction of the apical processes: around the apex we find four processes. They are all considered remnants of membranes between the four apical paraplates. Posterior to these, a second crown of several (in the holotype 10) processes occurs - the remnants of hollow membranes betweeen precingular and apical paraplates.
An archaeopyle was not observed in any specimeen. Based on the relation to M. perforata, an apical archaeopyle can be expected.
Dimensions: Holotype: Length (without processes) 55 Ám; width (without processes) 48 Ám; processes 12-18 Ám; other specimens: length (without processes) 45-60 Ám (average 53 Ám); width (without processes) 40-54 Ám (average 47 Ám); processes 7-18 Ám. 28 specimens.
Emended description: Masure, 1988, p. 365-366
Diagnosis: Chorate to proximochorate dinoflagellate cyst, acavate, subspherical, in outline rounded polygonal. Wall formed consisting of autophragm or closely appressed endophragm and periphragm, surface smooth to scabrate, granular at the bases of the processes. Paratabulation sexiform gonyaulacoid, indicated by intratabular, penitabular and parasutural processes. Ventral area undifferentiated. Processes granular and perforate, distally free, frequently interconnected proximally. Archaeopyle apical, type (tA)a, with accessory precingular sutures. Operculum composite adnate.
Emended description: Chorate to proximochorate, subspherical cyst, slightly dorsoventrally compressed. The polygonal outline is rounded asymmetrical, the epicystsmaller than the hypocyst. Wall consisting of autophragm or closely appressed endophragm and periphragm. Surface smooth to scabrate, granular at the bases of the processes. The granular and perforate processes, distally free, truncate or ramified, are frequently interconnected proximally. The paratabulation follows the sexiform gonyaulacoid model. According to the distribution of the processes, the apparent paratabulation is formed by 0-?2 preapical(s), 4 apicals, 6 precingulars, X cingulars, 5 postcingulars, ?1 postintercalary, 1 antapical, X sulcals. The sulcal paraplates and the sutures between the sulcus and adjacent paraplates (2, 1i, X, II and IV) are not expressed by reliefs. A preapical process may be present. Four or more processes ornament the apicals. penitabular processes, with adcingular interruptions, border the anterior part of the precingular paraplates. The sagging paracingulum is indicated by intratabular processes. Only the four postcingular parasutures II/III, III/IV, IV/V and V/VI bear processes. The antapical paraplate Y is delimited by parasutural processes; it may bear a bifid process. The apical archaeopyle is of the (tA)a type, with accessory sutures developed between the precingulars. The composite opeculum is adnate.
Affinities:
Masure, 1988, p. 365
Maghrebinia chleuh differs from the other Maghrebinia species in its distally isolated and proximally interconnected processes. According to Below, 1984, transitional forms between M. chleuh and M. mirabilis do exist.