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Pseudoceratium aulaeum
Pseudoceratium aulaeum Harding, 1990 ex Harding in Williams et al., 1998, p.512.
Name not validly published in Harding 1990 since lodgment of holotype was not specified (I.C.B.N. Article 37.5).
Holotype: Harding, 1990, pl.1, fig.1
Locus typicus: Warlingham borehole, England
Stratum typicum: Late Barremian
Original diagnosis: Harding, 1990, p.18
Shape: Ambitus typically ceratioid, with long apical horn and shorter antapical and postcingular horns. Epicyst longer than hypocyst by virtue of the long apical horn. Greatest width across post-cingular horn. Strong dorso-ventral compression.
Phragma: Autophragm ca. 0.2 µm thick, surface laevigate. Intratabular sculptural elements consist of irregularly distributed processes supporting an ectophragmal trabecular reticulum. Reticulum very variable, may be developed over the whole cyst (rare) or restricted to parts of the intratabular areas. Muri ca. 0.4 µm in diameter.
Paratabulation: Paratabulation corniform gonyaulacoid, expressed by parasutural areas devoid of sculpture: 4", 6", Xc, 7""", 1"""", 1p, Xs.
Archaeopyle: Type (tA), involving apical paraplates as a free, simple, polyplacoid operculum.
Paracingulum: Evidenced by lack of sculpture, individual paraplates not determined.
Parasulcus: Precise paratabulation not known, usually area of reduced sculpture, ai offset to the left.
Dimensions: Length, plus operculum (165) 144.1(130) µm. Width (56) 50.0 (39) µm. Length, less operculum (104) 89.8 (77) µm. Specimens = 29 (21).
Affinities:
Harding, 1990, p.18: This species has only been found in the presumed low-salinity assemblages of late Barremian age in the Warlingham borehole. It is distinguished from the other members of the genus by its surface sculpture. Most other species in the genus (including P. pelliferum) have intratabular processes of variable nature and of variable height but these are never connected distally by ectophragmal trabeculae as in P. auleum. Specimens identified as this new species were recorded by Lister & Batten (1988) as P. pelliferum.
Name not validly published in Harding 1990 since lodgment of holotype was not specified (I.C.B.N. Article 37.5).
Holotype: Harding, 1990, pl.1, fig.1
Locus typicus: Warlingham borehole, England
Stratum typicum: Late Barremian
Original diagnosis: Harding, 1990, p.18
Shape: Ambitus typically ceratioid, with long apical horn and shorter antapical and postcingular horns. Epicyst longer than hypocyst by virtue of the long apical horn. Greatest width across post-cingular horn. Strong dorso-ventral compression.
Phragma: Autophragm ca. 0.2 µm thick, surface laevigate. Intratabular sculptural elements consist of irregularly distributed processes supporting an ectophragmal trabecular reticulum. Reticulum very variable, may be developed over the whole cyst (rare) or restricted to parts of the intratabular areas. Muri ca. 0.4 µm in diameter.
Paratabulation: Paratabulation corniform gonyaulacoid, expressed by parasutural areas devoid of sculpture: 4", 6", Xc, 7""", 1"""", 1p, Xs.
Archaeopyle: Type (tA), involving apical paraplates as a free, simple, polyplacoid operculum.
Paracingulum: Evidenced by lack of sculpture, individual paraplates not determined.
Parasulcus: Precise paratabulation not known, usually area of reduced sculpture, ai offset to the left.
Dimensions: Length, plus operculum (165) 144.1(130) µm. Width (56) 50.0 (39) µm. Length, less operculum (104) 89.8 (77) µm. Specimens = 29 (21).
Affinities:
Harding, 1990, p.18: This species has only been found in the presumed low-salinity assemblages of late Barremian age in the Warlingham borehole. It is distinguished from the other members of the genus by its surface sculpture. Most other species in the genus (including P. pelliferum) have intratabular processes of variable nature and of variable height but these are never connected distally by ectophragmal trabeculae as in P. auleum. Specimens identified as this new species were recorded by Lister & Batten (1988) as P. pelliferum.