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Cordosphaeridium inodes ssp. inodes
Cordosphaeridium inodes ssp. inodes
Autonym
Originally Hystrichosphaeridium inodes ssp. inodes, subsequently (and now) Cordosphaeridium inodes ssp. inodes.
Holotype: Klumpp, 1953, pl.18, fig.1-2
Paratypes: Klumpp, 1953
Locus typicus: W÷hrden near Heide, Holstein, Germany
Stratum typicum: Late Eocene
Translations Klumpp, 1953, Eisenack, 1963 and Morgenroth, 1968: LPP
Translation Gocht, 1969: Geological Survey of Canada
Original description: Klumpp, 1953, p. 391-392: Hystrichosphaeridium inodes Diagnosis: A species of the genus Hystrichosphaeridium with the following special charaterictics: the shell membrane is bilayered, the outer layer consists of short fibres, standing perpendicular to the surface. From this fibrous layer the processes, irregularly fraying distally, are built.
Dimensions: diameter 64 Ám, process length 28-36 Ám. Variation: diameter 52-76 Ám, process length 20-40 Ám.
The size of the processes is very variable per specimen, and their number in several specimens is very diverse.
Davey and Williams, 1966, p. 84: Cordosphaeridium inodes
C. inodes has a fibrous body wall, bearing processes which give the reflected tabulation typical of this genus. The variability of processes, noticed by Klumpp, has also been observed in the London Clay forms, especially in the sulcal region. The processes are either hollow, open distally with an ellipsoidal cross-section or taeniate. The process walls of the London Clay specimens are extremely fibrous and appear to be thinner than in the type material, perhaps due to oxidation within the sediment.
Emended diagnosis: Morgenroth, 1968, p. 550: Cordosphaeridium inodes
(supplementary to the diagnosis of the genus) Theca generally clearly ellipsoidal, sometimes with small apical and antapical bulges. The massive processes are built from the fibrous layer of the thecal wall, tapering distally in a trumpet-shaped fashion. The length of the processes varies considerably per specimen (differences in lenght of up to 15 Ám have been observed). A number of specimens shows the tendency of a distal interconnection of neighbouring processes. The arrangement of processes is as follows: 4 apical processes - sometimes coalescing - characterize the apex. A further apical process is located on the epitheca in direct line with the ventral longitudinal zone. Above the girdle zone, 6 precingular processes are present. In some specimens, the laevorotatory girdle is characterized by an continuous fibrous band. In most of the specimens, 6 processes, more or less stretched in the direction of the girdle, can be observed in that place. The girdle is interrupted ventrally by a narrow longitudinal zone, on the hypothecal part of which a small process is sometimes present. On the hypotheca, 6 postequatorial and 1 long antapical process can be discerned. In a few specimens, however, a further small process is located below 1""", taking the position of an intercalary plate. (Presumably, the intercalary process sometimes fuses with 1""" into a more robust process.)
Dimensions: theca length 68 (53/81) µm, theca width 59 (50/70) µm, process length c. 25-30 (19/43) µm. 150 measurements, 1200 specimens studied.
Gocht, 1969, p.41:
This subspecies is recognizable by its broad, usually somewhat flattened processes of very variable length. The fibrous structure of the processes is distinct; they widen distally and frequently end as if cut along a straight or convex line. However, also deeply slit or branched ends occur, or the processes may be coming apart into separate fibers down deep into the shaft, or perforated. There are transitional forms toward the other subspecies, particularly C. inodes gracilis. Both subspecies are included in the tables. Forms with broad, relatively fragile processes approach C. exilimurum Davey and Williams, 1966.
Material and occurence: see remarks Gocht, 1969 C. i. gracilis.
Autonym
Originally Hystrichosphaeridium inodes ssp. inodes, subsequently (and now) Cordosphaeridium inodes ssp. inodes.
Holotype: Klumpp, 1953, pl.18, fig.1-2
Paratypes: Klumpp, 1953
Locus typicus: W÷hrden near Heide, Holstein, Germany
Stratum typicum: Late Eocene
Translations Klumpp, 1953, Eisenack, 1963 and Morgenroth, 1968: LPP
Translation Gocht, 1969: Geological Survey of Canada
Original description: Klumpp, 1953, p. 391-392: Hystrichosphaeridium inodes Diagnosis: A species of the genus Hystrichosphaeridium with the following special charaterictics: the shell membrane is bilayered, the outer layer consists of short fibres, standing perpendicular to the surface. From this fibrous layer the processes, irregularly fraying distally, are built.
Dimensions: diameter 64 Ám, process length 28-36 Ám. Variation: diameter 52-76 Ám, process length 20-40 Ám.
The size of the processes is very variable per specimen, and their number in several specimens is very diverse.
Davey and Williams, 1966, p. 84: Cordosphaeridium inodes
C. inodes has a fibrous body wall, bearing processes which give the reflected tabulation typical of this genus. The variability of processes, noticed by Klumpp, has also been observed in the London Clay forms, especially in the sulcal region. The processes are either hollow, open distally with an ellipsoidal cross-section or taeniate. The process walls of the London Clay specimens are extremely fibrous and appear to be thinner than in the type material, perhaps due to oxidation within the sediment.
Emended diagnosis: Morgenroth, 1968, p. 550: Cordosphaeridium inodes
(supplementary to the diagnosis of the genus) Theca generally clearly ellipsoidal, sometimes with small apical and antapical bulges. The massive processes are built from the fibrous layer of the thecal wall, tapering distally in a trumpet-shaped fashion. The length of the processes varies considerably per specimen (differences in lenght of up to 15 Ám have been observed). A number of specimens shows the tendency of a distal interconnection of neighbouring processes. The arrangement of processes is as follows: 4 apical processes - sometimes coalescing - characterize the apex. A further apical process is located on the epitheca in direct line with the ventral longitudinal zone. Above the girdle zone, 6 precingular processes are present. In some specimens, the laevorotatory girdle is characterized by an continuous fibrous band. In most of the specimens, 6 processes, more or less stretched in the direction of the girdle, can be observed in that place. The girdle is interrupted ventrally by a narrow longitudinal zone, on the hypothecal part of which a small process is sometimes present. On the hypotheca, 6 postequatorial and 1 long antapical process can be discerned. In a few specimens, however, a further small process is located below 1""", taking the position of an intercalary plate. (Presumably, the intercalary process sometimes fuses with 1""" into a more robust process.)
Dimensions: theca length 68 (53/81) µm, theca width 59 (50/70) µm, process length c. 25-30 (19/43) µm. 150 measurements, 1200 specimens studied.
Gocht, 1969, p.41:
This subspecies is recognizable by its broad, usually somewhat flattened processes of very variable length. The fibrous structure of the processes is distinct; they widen distally and frequently end as if cut along a straight or convex line. However, also deeply slit or branched ends occur, or the processes may be coming apart into separate fibers down deep into the shaft, or perforated. There are transitional forms toward the other subspecies, particularly C. inodes gracilis. Both subspecies are included in the tables. Forms with broad, relatively fragile processes approach C. exilimurum Davey and Williams, 1966.
Material and occurence: see remarks Gocht, 1969 C. i. gracilis.