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Pilosidinium neophytensum
Pilosidinium neophytensum (Ioannides et al., 1977) Courtinat, 1989
Originally Tenua Eisenack, 1958, subsequently Sentusidinium?, thirdly (and now)
Pilosidinium.
Holotype: Ioannides et al. 1977, pl.5, fig.5
Locus typicus: Clavell"s Hard, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Ioannides et al. 1977, p. 463: Tenua neophytensa
Proximate cysts with ovoidal shell; surface densely covered with short processes of variable shape. Apex invariably surmounted by process longer and stronger than others. No indication of tabulation observed but cingulum and sulcus sometimes vaguely suggested by narrow folds. Archaeopyle apical with zigzag margin; operculum frequently attached to shell.
Original description: Ioannides et al. 1977, p. 463: Tenua neophytensa
Shell densely covered with short acuminate to capitate, rarely bifurcate, slender solid processes, sometimes of unequal size on individual specimen. An apical prominent process always present, approximately twice the length and thickness of other processes. One of the antapical processes sometimes slightly longer than others. Tabulation never observed but cingulum and sulcus may be weakly suggested by disposition of narrow folds in median and longitudinal zones, respectively. Archaeopyle, when developed, apical: operculum often remains attached to shell.
Dimensions. Range: shell length 34-46 µm, breadth 26-35 µm: length of processes 1-4 µm apical process 4-6.5 µm (22 specimens measured).
Affinities:
Ioannides et al. 1977, p. 463: Tenua neophytensa
The prominent apical process renders the species highly distinguishable. Cometodinium obscurum Deflandre and Courteville, 1939, has long, hairlike processes and a definite cingulum.
Originally Tenua Eisenack, 1958, subsequently Sentusidinium?, thirdly (and now)
Pilosidinium.
Holotype: Ioannides et al. 1977, pl.5, fig.5
Locus typicus: Clavell"s Hard, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Ioannides et al. 1977, p. 463: Tenua neophytensa
Proximate cysts with ovoidal shell; surface densely covered with short processes of variable shape. Apex invariably surmounted by process longer and stronger than others. No indication of tabulation observed but cingulum and sulcus sometimes vaguely suggested by narrow folds. Archaeopyle apical with zigzag margin; operculum frequently attached to shell.
Original description: Ioannides et al. 1977, p. 463: Tenua neophytensa
Shell densely covered with short acuminate to capitate, rarely bifurcate, slender solid processes, sometimes of unequal size on individual specimen. An apical prominent process always present, approximately twice the length and thickness of other processes. One of the antapical processes sometimes slightly longer than others. Tabulation never observed but cingulum and sulcus may be weakly suggested by disposition of narrow folds in median and longitudinal zones, respectively. Archaeopyle, when developed, apical: operculum often remains attached to shell.
Dimensions. Range: shell length 34-46 µm, breadth 26-35 µm: length of processes 1-4 µm apical process 4-6.5 µm (22 specimens measured).
Affinities:
Ioannides et al. 1977, p. 463: Tenua neophytensa
The prominent apical process renders the species highly distinguishable. Cometodinium obscurum Deflandre and Courteville, 1939, has long, hairlike processes and a definite cingulum.