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Pilosidinium echinatum
Pilosidinium echinatum (Gitmez and Sarjeant, 1972) Courtinat, 1989
Originally Tenua Eisenack, 1958, subsequently Sentusidinium, thirdly
Batiacasphaera, fourthly (and now) Pilosidinium.
Holotype: Gitmez and Sarjeant, 1972, pl.1, fig.1
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Osmington Mills, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Gitmez and Sarjeant, 1972, p.190: Tenua echinata
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 50µm, breadth 50µm; length without apex 43µm; length of the spines 2µm. Paratype: overall length 72µm, breadth 60µm; length of the spines 2-5µm. Overall range of the English specimens (15 specimens measured): length 45-50µm breadth 40-80µm, length without apex (3 specimens were observed without apex) 43µm; length of the spines 1.5-2.5µm.
Dimensions of the single French specimen encountered: length (apex lacking) 38µm, breadth 40µm; length of spines 2µm.
Original description: Gitmez and Sarjeant, 1972, p.190: Tenua echinata
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: Tenua echinata
This new species of Tenua differs from previously described species of the genus in its characteristic shape and in the nature of its spines.
Originally Tenua Eisenack, 1958, subsequently Sentusidinium, thirdly
Batiacasphaera, fourthly (and now) Pilosidinium.
Holotype: Gitmez and Sarjeant, 1972, pl.1, fig.1
Paratype: Gitmez and Sarjeant, 1972
Locus typicus: Osmington Mills, Dorset, England
Stratum typicum: Kimmeridgian
Original diagnosis: Gitmez and Sarjeant, 1972, p.190: Tenua echinata
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 50µm, breadth 50µm; length without apex 43µm; length of the spines 2µm. Paratype: overall length 72µm, breadth 60µm; length of the spines 2-5µm. Overall range of the English specimens (15 specimens measured): length 45-50µm breadth 40-80µm, length without apex (3 specimens were observed without apex) 43µm; length of the spines 1.5-2.5µm.
Dimensions of the single French specimen encountered: length (apex lacking) 38µm, breadth 40µm; length of spines 2µm.
Original description: Gitmez and Sarjeant, 1972, p.190: Tenua echinata
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: Tenua echinata
This new species of Tenua differs from previously described species of the genus in its characteristic shape and in the nature of its spines.