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Kleithriasphaeridium loffrense
Kleithriasphaeridium loffrensis Davey and Verdier, 1976, p.310-312
Taxonomic junior synonym: Florentinia aculeata, according to Fensome et al. (2009, p.42).
Holotype: Davey and Verdier, 1976, pl.1, figs,1-2
Paratype: Davey and Verdier, 1976
Locus typicus: Loffre Borehole, Nord, France
Stratum typicum: Senonian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Kleithriasphaeridium loffrense Davey and Verdier, 1974. The central body is smooth-walled, and bears one tubular process per paraplate. The processes are all of comparable length but variable in width. The most slender processes are in the sulcal area and the broadest are postcingular. The processes are approximately parallel sided for most of their length; they widen proximally and distally are open, terminating with a spiny to secate margin. Central body diameter 45-52 µm, process length 30-38 µm.
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Original diagnosis: Davey and Verdier, 1976, p.310-311
The central body is spherical to subspherical, smooth-walled and bears one tubular process per reflected area. The processes are all of comparable length but vary somewhat in width--the finest processes are in the sulcal region and the broadest occupy the postcingular region. The processes are approximately parallel-sided for most of their length; they widen proximally and distally are open terminating with a spiny to secate margin. A precingular (3") archaeopyle is typically developed.
Dimensions: Range: Central body diameter: 45-52 µm; length of processes: 30-38 µm.
Original description: Davey and Verdier, 1976, p.312
This is a simple species with relatively little morphological variation being apparent. The central body is thin-walled and is easily distorted. Hence, although the archaeopyle may be visible, its characteristic precingular shape is not observable and, using it as the only criterion, orientation is usually impossible. Orientation is considerably assisted by the location of a small apical boss which may or may not be present. On an individual, variation in process width is not great and the variation is continuous from the widest to the thinnest. Thus assignation of a process to a particular series is difficult and size variation does not help significantly in cyst orientation.
Affinities:
Davey and Verdier, 1976, p. 312: The most similar species to K. Ioffrensis is Florentinia deanei (Davey et Williams 1966) which differs primarily in having a precingular (3")-apical combination archaeopyle and a distinctively large, lagenate antapical process which is rounded distally. The processes on an individual F. deanei are also more variable in size than on a specimen of K. Ioffrensis.
K. loffrensis has up to now been confused with Hystrichosphaeridium stellatum Maier (1959) from the Oligocene to Miocene of Germany because of difficulties in onentating and defining the former species and comparing the two species. However, it is now apparent that H. stellatum has two types of processes, one wide, the other relatively narrow, and may be better placed in the genus Hystrichokolpoma if the archaeopyle is indeed apical.
A third species which apparently can only be reliably differentiated from K. loffrensis by its apical archaeopyle is Hystrichosphaeridium tubiferum (Ehrenberg 1838).
Taxonomic junior synonym: Florentinia aculeata, according to Fensome et al. (2009, p.42).
Holotype: Davey and Verdier, 1976, pl.1, figs,1-2
Paratype: Davey and Verdier, 1976
Locus typicus: Loffre Borehole, Nord, France
Stratum typicum: Senonian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Kleithriasphaeridium loffrense Davey and Verdier, 1974. The central body is smooth-walled, and bears one tubular process per paraplate. The processes are all of comparable length but variable in width. The most slender processes are in the sulcal area and the broadest are postcingular. The processes are approximately parallel sided for most of their length; they widen proximally and distally are open, terminating with a spiny to secate margin. Central body diameter 45-52 µm, process length 30-38 µm.
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Original diagnosis: Davey and Verdier, 1976, p.310-311
The central body is spherical to subspherical, smooth-walled and bears one tubular process per reflected area. The processes are all of comparable length but vary somewhat in width--the finest processes are in the sulcal region and the broadest occupy the postcingular region. The processes are approximately parallel-sided for most of their length; they widen proximally and distally are open terminating with a spiny to secate margin. A precingular (3") archaeopyle is typically developed.
Dimensions: Range: Central body diameter: 45-52 µm; length of processes: 30-38 µm.
Original description: Davey and Verdier, 1976, p.312
This is a simple species with relatively little morphological variation being apparent. The central body is thin-walled and is easily distorted. Hence, although the archaeopyle may be visible, its characteristic precingular shape is not observable and, using it as the only criterion, orientation is usually impossible. Orientation is considerably assisted by the location of a small apical boss which may or may not be present. On an individual, variation in process width is not great and the variation is continuous from the widest to the thinnest. Thus assignation of a process to a particular series is difficult and size variation does not help significantly in cyst orientation.
Affinities:
Davey and Verdier, 1976, p. 312: The most similar species to K. Ioffrensis is Florentinia deanei (Davey et Williams 1966) which differs primarily in having a precingular (3")-apical combination archaeopyle and a distinctively large, lagenate antapical process which is rounded distally. The processes on an individual F. deanei are also more variable in size than on a specimen of K. Ioffrensis.
K. loffrensis has up to now been confused with Hystrichosphaeridium stellatum Maier (1959) from the Oligocene to Miocene of Germany because of difficulties in onentating and defining the former species and comparing the two species. However, it is now apparent that H. stellatum has two types of processes, one wide, the other relatively narrow, and may be better placed in the genus Hystrichokolpoma if the archaeopyle is indeed apical.
A third species which apparently can only be reliably differentiated from K. loffrensis by its apical archaeopyle is Hystrichosphaeridium tubiferum (Ehrenberg 1838).