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Labyrinthodinium truncatum var. truncatum
Labyrinthodinium truncatum var. truncatum
Autonym
Holotype: Piasecki, 1980, pl. 2, fig. 9-11
Paratypes: Piasecki, 1980
Locus typicus: Gram Bore (DGU file 141 423), Gram, Denmark
Stratum typicum: Middle Miocene
Original description: Piasecki, 1980, p. 67.
Diagnosis: Small chorate cysts with spherical main body, composed of two wall layers. Endophragma is hyalin and structureless, periphragma is smooth to spongeous at the surface of the main body, and smooth with scattered microgranulaes when forming crests and processes. Periphragma form an open reticulum of crests from which membraneous processes arise. All the processes are equal length and slightly expanded distally into small platforms. The archaeopyle is large and polygonal of type (tA).
Description (annotated): Endophragma is constant thickness, while periphragma may be thin an smooth or thick and spongeous. The wall thickness range from 1-3 Á, mainly because of the variation of periphragma. The two wall layers are not clearly separable when periphragma is thin and smooth. The crests on the surface of the cysts may either form a dense reticulum with a large number of processes or a rude pattern with open meshes and few processes. The reticulum may reflect a undeterminable paratabulation, because some of the crests appear to form a superior pattern from which the processes arise. Further, the archaeopyle suture does not cross the crests, which are conformable with archaeopyle margin and partly with the accessory archaeopyle sutures. The processes are formed of several adjoining crests or membranes, and are all of the same length on one cyst.
They are expanded distally building up a small platform. No structures reflecting paratabulation, paracingulum or parasulcus have been observed, except for the archaeopyle sutures. The archaeopyle is apical: type (tA). It is large and polygonal, and small accessory sutures are present along the margin.
Dimensions: Holotype: diameter 25 Ám, length of processes 5 Ám, wall thickness 1 Ám. Range: diameter 23(29)40 Ám, proces length 4(6)10 Ám, wall thickness 1-3 Ám.
Affinities:
Piasecki, 1980: These cysts do not belong to Cordosphaeridium (Eisenack) Davey, because they do not have intratabular fibrous processes and a precingular archaeopyle.
Autonym
Holotype: Piasecki, 1980, pl. 2, fig. 9-11
Paratypes: Piasecki, 1980
Locus typicus: Gram Bore (DGU file 141 423), Gram, Denmark
Stratum typicum: Middle Miocene
Original description: Piasecki, 1980, p. 67.
Diagnosis: Small chorate cysts with spherical main body, composed of two wall layers. Endophragma is hyalin and structureless, periphragma is smooth to spongeous at the surface of the main body, and smooth with scattered microgranulaes when forming crests and processes. Periphragma form an open reticulum of crests from which membraneous processes arise. All the processes are equal length and slightly expanded distally into small platforms. The archaeopyle is large and polygonal of type (tA).
Description (annotated): Endophragma is constant thickness, while periphragma may be thin an smooth or thick and spongeous. The wall thickness range from 1-3 Á, mainly because of the variation of periphragma. The two wall layers are not clearly separable when periphragma is thin and smooth. The crests on the surface of the cysts may either form a dense reticulum with a large number of processes or a rude pattern with open meshes and few processes. The reticulum may reflect a undeterminable paratabulation, because some of the crests appear to form a superior pattern from which the processes arise. Further, the archaeopyle suture does not cross the crests, which are conformable with archaeopyle margin and partly with the accessory archaeopyle sutures. The processes are formed of several adjoining crests or membranes, and are all of the same length on one cyst.
They are expanded distally building up a small platform. No structures reflecting paratabulation, paracingulum or parasulcus have been observed, except for the archaeopyle sutures. The archaeopyle is apical: type (tA). It is large and polygonal, and small accessory sutures are present along the margin.
Dimensions: Holotype: diameter 25 Ám, length of processes 5 Ám, wall thickness 1 Ám. Range: diameter 23(29)40 Ám, proces length 4(6)10 Ám, wall thickness 1-3 Ám.
Affinities:
Piasecki, 1980: These cysts do not belong to Cordosphaeridium (Eisenack) Davey, because they do not have intratabular fibrous processes and a precingular archaeopyle.