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Homotryblium tenuispinosum
Homotryblium tenuispinosum Davey and Williams, 1966, p.101-102
Taxonomic junior synonym: Homotryblium pallidum, according to Edwards (1996, p.989).
Holotype: Davey and Williams, 1966, pl.12, fig.5
Locus typicus: London Clay, Enborn, Berkshire, England
Stratum typicum: Early Eocene
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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.
Homotryblium tenuispinosum Davey and Williams, 1966b, has a spherical central body with wall composed of thin layers, smooth endophragm and strongly granular periphragm. Processes erect or curved, tubiform simple, open distally with serrate or aculeate margin, rarely perforate. Width of processes variable. Size: diameter of central body 41-57 µm, process length 13-32 µm.
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Davey and Williams 1966, p. 101-102
Diagnosis: Spherical central body with wall composed of thin layers-smooth inner endophragm, outer strongly granular periphragm. Processes erect or curved, tubiform, simple, open distally with serrate or aculeate margin, rarely perforate.
Width of processes variable.
Dimensions: Range: diameter of the central body: 41-57 Ám; length of processes: 13-32 Ám. Number of specimens measured: 8.
Description: The processes are restricted to one per plate area and indicate a reflected tabulation of 3', 6'', 6c, 5''', 1p, 1'''' and 1-5s. The equatorial and sulcal processes are frequently more slender than the others. Distally the processes often have a margin bearing short bifid aculei. The length of the processes is about half the diameter of the central body. The margin of the archaeopyle is interrupted on the epitract by a short projection, the sulcal tongue (Evitt). This has a corresponding sulcal notch on the hypotract. The number of sulcalprocesses varies from 1 to 5. In some specimens the plates readily separate, save for three apicals which have never been observed as individual plates.
Affinities:
Davey and Williams, 1966, p. 102
From the nature of the archaeopyle, the coarsely granular wall and the tabulation, H. tenuispinosum is distinct from all previously described species.
Taxonomic junior synonym: Homotryblium pallidum, according to Edwards (1996, p.989).
Holotype: Davey and Williams, 1966, pl.12, fig.5
Locus typicus: London Clay, Enborn, Berkshire, England
Stratum typicum: Early Eocene
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Homotryblium tenuispinosum Davey and Williams, 1966b, has a spherical central body with wall composed of thin layers, smooth endophragm and strongly granular periphragm. Processes erect or curved, tubiform simple, open distally with serrate or aculeate margin, rarely perforate. Width of processes variable. Size: diameter of central body 41-57 µm, process length 13-32 µm.
--------------------------------------------------
Davey and Williams 1966, p. 101-102
Diagnosis: Spherical central body with wall composed of thin layers-smooth inner endophragm, outer strongly granular periphragm. Processes erect or curved, tubiform, simple, open distally with serrate or aculeate margin, rarely perforate.
Width of processes variable.
Dimensions: Range: diameter of the central body: 41-57 Ám; length of processes: 13-32 Ám. Number of specimens measured: 8.
Description: The processes are restricted to one per plate area and indicate a reflected tabulation of 3', 6'', 6c, 5''', 1p, 1'''' and 1-5s. The equatorial and sulcal processes are frequently more slender than the others. Distally the processes often have a margin bearing short bifid aculei. The length of the processes is about half the diameter of the central body. The margin of the archaeopyle is interrupted on the epitract by a short projection, the sulcal tongue (Evitt). This has a corresponding sulcal notch on the hypotract. The number of sulcalprocesses varies from 1 to 5. In some specimens the plates readily separate, save for three apicals which have never been observed as individual plates.
Affinities:
Davey and Williams, 1966, p. 102
From the nature of the archaeopyle, the coarsely granular wall and the tabulation, H. tenuispinosum is distinct from all previously described species.