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Fromea expolita
Fromea expolita (Brideaux, 1977) Lentin and Williams, 1981
Originally Palaeostomocystis, subsequently (and now) Fromea.
Holotype: Brideaux, 1977, pl.7, figs.12-14
Locus typicus: Richardson Mountains, District of Mackenzie, Canada
Stratum typicum: Barremian
Original diagnosis: Brideaux, 1977, p. 20: Palaeostomocystis expolita
Shape: Autocyst length equal to or greater than maximum width; pear-shaped to trianguloid outline; autocyst narrowest apically, the sides straight or slightly convex, widening abruptly at about two thirds of the total length; straight or slightly invaginated in the median antapical part; lower third of the autocyst bilobed or at least expanded, the corners rounded; well-developed lobations commonly compressed and folded, rarely extended. Dorso-ventral compression.
Phragma: Autophragm from 1.0-1.5 Ám thick; smooth or faintly scabrate.
Paratabulation: Evidence for determinable paratabulation lacking, the subangular outline of the apical archeopyle on many specimens indicating presence of apical paratabulation.
Archeopyle/operculum: Archeopyle apical, formed by the loss of a subcircular to subangular part of the apex, the archeopyle opening indistinctly to recognizably angular. Operculum flat, subrounded; generally detached, but occasionally in place (holotype) or lying in the autocoel. Formula A.
Pericingulum/perisulcus: Not observed.
Affinities:
Brideaux, 1977, p. 20: Palaeostomocystis expolita
Palaeostomocystis expolita differs from Palaeostomocystis triquetra in possessing a smooth or scabrate autophragm, and from other published species of the genus in its shape Horologinella sp. indet. of Cookson and Eisenack, 1962, possesses apiculate sculpture and is smaller. Other remarks made in the comparison section under Palaeostomocystis triquetra also apply here in part.
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Fromea aff. expolita of Nohr-Hansen 1993
Comments: Norh-Hansen 1993, p. 68
The specimens recorded in the present study resemble Fromea expolita (brideaux, 1977) Lentin & Williams, 1981 in their pear-shaped to triangular outline and in their smooth to scabrate surface, but differ by a smaller length (50-60Á) and width (50-60Á) compared to the length (65-100Á) and width (70-86Á) for the type material.
Occurence in east Greenland: Restricted to the uppermost Albian. Sections 24, 25, 30 and 37.
Preveious occurence: Fromea expolita was previously only recorded from the Hauterivian and Barremian in the district of MacKenzie, Canada (Brideaux, 1977).
Originally Palaeostomocystis, subsequently (and now) Fromea.
Holotype: Brideaux, 1977, pl.7, figs.12-14
Locus typicus: Richardson Mountains, District of Mackenzie, Canada
Stratum typicum: Barremian
Original diagnosis: Brideaux, 1977, p. 20: Palaeostomocystis expolita
Shape: Autocyst length equal to or greater than maximum width; pear-shaped to trianguloid outline; autocyst narrowest apically, the sides straight or slightly convex, widening abruptly at about two thirds of the total length; straight or slightly invaginated in the median antapical part; lower third of the autocyst bilobed or at least expanded, the corners rounded; well-developed lobations commonly compressed and folded, rarely extended. Dorso-ventral compression.
Phragma: Autophragm from 1.0-1.5 Ám thick; smooth or faintly scabrate.
Paratabulation: Evidence for determinable paratabulation lacking, the subangular outline of the apical archeopyle on many specimens indicating presence of apical paratabulation.
Archeopyle/operculum: Archeopyle apical, formed by the loss of a subcircular to subangular part of the apex, the archeopyle opening indistinctly to recognizably angular. Operculum flat, subrounded; generally detached, but occasionally in place (holotype) or lying in the autocoel. Formula A.
Pericingulum/perisulcus: Not observed.
Affinities:
Brideaux, 1977, p. 20: Palaeostomocystis expolita
Palaeostomocystis expolita differs from Palaeostomocystis triquetra in possessing a smooth or scabrate autophragm, and from other published species of the genus in its shape Horologinella sp. indet. of Cookson and Eisenack, 1962, possesses apiculate sculpture and is smaller. Other remarks made in the comparison section under Palaeostomocystis triquetra also apply here in part.
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Fromea aff. expolita of Nohr-Hansen 1993
Comments: Norh-Hansen 1993, p. 68
The specimens recorded in the present study resemble Fromea expolita (brideaux, 1977) Lentin & Williams, 1981 in their pear-shaped to triangular outline and in their smooth to scabrate surface, but differ by a smaller length (50-60Á) and width (50-60Á) compared to the length (65-100Á) and width (70-86Á) for the type material.
Occurence in east Greenland: Restricted to the uppermost Albian. Sections 24, 25, 30 and 37.
Preveious occurence: Fromea expolita was previously only recorded from the Hauterivian and Barremian in the district of MacKenzie, Canada (Brideaux, 1977).