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Cordosphaeridium callosum
From Fensome et al., 2019:
Cordosphaeridium? callosum Morgenroth, 1966a, p.21, pl.4, figs.8–10. Holotype: Morgenroth, 1966a, pl.4, figs.9–10. Originally Cordosphaeridium, subsequently (and now) Cordosphaeridium?, thirdly Tityrosphaeridium?. Lentin and Williams (1985, p.70) retained this species in Cordosphaeridium?. Questionable assignment: Stover and Evitt (1978, p.147). Age: Early Eocene.
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Original description: [Morgenroth, 1966a] (translated from German):
Cordosphaeridium callosum n. sp.
Plate 4 Fig. 8-10
Derivio nominis: callosus lat.: thick-skinned.
Holotype: The specimen preserved in specimen no. HF 6 and illustrated on Plate 4 Fig. 9-10.
Paratypoids: HF41, HF50, HF53, H73, H82.
Locus typicus: Fehmarn, Katbarinenhof.
Stratum typicalum: Lower Eocene (?2).
Diagnosis: A very small species of the genus Cordosphaeridium with a very pronounced fibrous layer (3 μ!). The capsule is spherical. The distal processes are trumpet-shaped.
Description: The wall of the very small, spherical capsule consists of two layers, of which the smooth inner layer is very thin, while the outer layer is approximately 3 μ thick. At the highest magnification, it can be seen that the latter is composed of a very loose fibrous network (cf. Figs. 9 and 10), which appears like a tangle of fibers on the capsule surface. The numerous massive processes are formed from these fibers. A slender central section is followed distally by a funnel-shaped expansion. Pyrite deposits in some cases indicate the occasional presence of isolated cavities. One capsule has a rounded rectangular opening (Ø 11 μ), which can probably be interpreted as a pyloma!
Remarks: Cordosphaeridium callosum differs from the already known species of this genus by:
1. the exceptionally thick fibrous layer of the capsule wall, from which up to approximately 30 uniform, slender processes are formed.
2. its smaller dimensions.
Dimensions: Inner capsule Ø 20μ (17μ/22μ), length of the processes 8μ-11μ, thickness of the capsule wall 3μ (7 measurements!). Number of specimens examined: 7.
Cordosphaeridium? callosum Morgenroth, 1966a, p.21, pl.4, figs.8–10. Holotype: Morgenroth, 1966a, pl.4, figs.9–10. Originally Cordosphaeridium, subsequently (and now) Cordosphaeridium?, thirdly Tityrosphaeridium?. Lentin and Williams (1985, p.70) retained this species in Cordosphaeridium?. Questionable assignment: Stover and Evitt (1978, p.147). Age: Early Eocene.
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Original description: [Morgenroth, 1966a] (translated from German):
Cordosphaeridium callosum n. sp.
Plate 4 Fig. 8-10
Derivio nominis: callosus lat.: thick-skinned.
Holotype: The specimen preserved in specimen no. HF 6 and illustrated on Plate 4 Fig. 9-10.
Paratypoids: HF41, HF50, HF53, H73, H82.
Locus typicus: Fehmarn, Katbarinenhof.
Stratum typicalum: Lower Eocene (?2).
Diagnosis: A very small species of the genus Cordosphaeridium with a very pronounced fibrous layer (3 μ!). The capsule is spherical. The distal processes are trumpet-shaped.
Description: The wall of the very small, spherical capsule consists of two layers, of which the smooth inner layer is very thin, while the outer layer is approximately 3 μ thick. At the highest magnification, it can be seen that the latter is composed of a very loose fibrous network (cf. Figs. 9 and 10), which appears like a tangle of fibers on the capsule surface. The numerous massive processes are formed from these fibers. A slender central section is followed distally by a funnel-shaped expansion. Pyrite deposits in some cases indicate the occasional presence of isolated cavities. One capsule has a rounded rectangular opening (Ø 11 μ), which can probably be interpreted as a pyloma!
Remarks: Cordosphaeridium callosum differs from the already known species of this genus by:
1. the exceptionally thick fibrous layer of the capsule wall, from which up to approximately 30 uniform, slender processes are formed.
2. its smaller dimensions.
Dimensions: Inner capsule Ø 20μ (17μ/22μ), length of the processes 8μ-11μ, thickness of the capsule wall 3μ (7 measurements!). Number of specimens examined: 7.