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Tenua echinata
Tenua echinata Gitmez and Sarjeant, 1972
Now Pilosidinium. Originally Tenua Eisenack, 1958, subsequently Sentusidinium, thirdly Batiacasphaera, fourthly (and now) Pilosidinium.
Holotype: Gitmez and Sarjeant, 1972, pl.1, fig.1; Fauconnier and Masure, 2004, pl.63, fig.14.
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Osmington Mills, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Gitmez and Sarjeant, 1972, p.190
Cyst spherical, subspherical or broadly ovoidal, covered with spines and looking like a prickly ball. Spines very short, broad-based and conical, uniformly distributed over the whole surface, over 200 in number. There is no indication of tabulation, cingulum or sulcus. Archaeopyle usually present, apical in position; the operculum usually remains attached on one side but is sometimes completely lost.
Dimensions: Holotype: overall length 50 µm, breadth 50 µm; length without apex 43 µm; length of the spines 2 µm. Paratype: overall length 72 µm, breadth 60 µm; length of the spines 2-5 µm. Overall range of the English specimens (15 specimens measured): length 45-50 µm breadth 40-80 µm, length without apex (3 specimens were observed without apex) 43 µm; length of the spines 1.5-2.5 µm.
Dimensions of the single French specimen encountered: length (apex lacking) 38 µm, breadth 40 µm; length of spines 2 µm.
Original description: Gitmez and Sarjeant, 1972, p.190
The shell surface is smooth. The apex is typically detached in archaeopyle formation. The margin of the archaeopyle is roughly polygonal, with tears extending from the angles along the presumed lines of a reflected tabulation. When the operculum remains attached on one side, this side is probably the ventral side. The spines appear to be solid.
Affinities:
Gitmez and Sarjeant, 1972, p.190: This new species of Tenua differs from previously described species of the genus in its characteristic shape and in the nature of its spines.
Now Pilosidinium. Originally Tenua Eisenack, 1958, subsequently Sentusidinium, thirdly Batiacasphaera, fourthly (and now) Pilosidinium.
Holotype: Gitmez and Sarjeant, 1972, pl.1, fig.1; Fauconnier and Masure, 2004, pl.63, fig.14.
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Osmington Mills, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Gitmez and Sarjeant, 1972, p.190
Cyst spherical, subspherical or broadly ovoidal, covered with spines and looking like a prickly ball. Spines very short, broad-based and conical, uniformly distributed over the whole surface, over 200 in number. There is no indication of tabulation, cingulum or sulcus. Archaeopyle usually present, apical in position; the operculum usually remains attached on one side but is sometimes completely lost.
Dimensions: Holotype: overall length 50 µm, breadth 50 µm; length without apex 43 µm; length of the spines 2 µm. Paratype: overall length 72 µm, breadth 60 µm; length of the spines 2-5 µm. Overall range of the English specimens (15 specimens measured): length 45-50 µm breadth 40-80 µm, length without apex (3 specimens were observed without apex) 43 µm; length of the spines 1.5-2.5 µm.
Dimensions of the single French specimen encountered: length (apex lacking) 38 µm, breadth 40 µm; length of spines 2 µm.
Original description: Gitmez and Sarjeant, 1972, p.190
The shell surface is smooth. The apex is typically detached in archaeopyle formation. The margin of the archaeopyle is roughly polygonal, with tears extending from the angles along the presumed lines of a reflected tabulation. When the operculum remains attached on one side, this side is probably the ventral side. The spines appear to be solid.
Affinities:
Gitmez and Sarjeant, 1972, p.190: This new species of Tenua differs from previously described species of the genus in its characteristic shape and in the nature of its spines.