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Surculosphaeridium longifurcatum
Surculosphaeridium? longifurcatum (Firtion, 1952, p.157–158, pl.9, fig.1; text-figs.1H–M) Davey et al., 1966, p.163.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Acritarch), thirdly (and now) Surculosphaeridium, fourthly Surculosphaeridium?. Questionable assignment: Stover and Evitt (1978, p.83) — however, Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.517) considered that this species should be assigned to Surculosphaeridium without question.
Holotype: Firtion, 1952, pl.9, fig.1; lost according to Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.517).
Neotype: Foucher, 1976, pl.5, figs.7–8, designated by Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.518); Fauconnier and Masure, 2004, pl.74, figs.2–3.
Locus typicus: Nouvion-en-ThiÚrache, France
Stratum typicum: Cenomanian
Translation, Firton: LPP
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Surculosphaeridium longifurcatum (Firtion, 1952) Davey et al., 1966. From Davey et al. (1966). Central body subspherical. Periphragm smooth with about 26 processes in a complete specimen. Processes closed distally and rather variable, being simple, lobate, foliate or digitate. Some of the processes, especially on the cingulum, are deeply notched. Sometimes there appear to be two cingular processes. Tabulation given as 4', 6", 6c, 6"’, 1p, 3"”. Archeopyle apical, type (tA). Size: type material, central body diameter 40.6 µm, processes 20.4 µm.
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Original description: Firtion, p. 157-158: Hystrichospaeridium longifurcatum.
In this species, the pale body is globular. It differs from H. multifurcatum Deflandre by its longer processes and deeper bifurcations.
Emended description: Davey et al., 1966, p. 163-164
The central body is subspherical. The periphragm is smooth and gives rise to a more or less constant 26 processes in a complete specimen. An angular archaeopyle is commonly present, the detached apical region bearing 4 apical processes. The processes are closed distally and are rather variable in form, being simple, lobate foliate or digitate. Some of the processes, particularly those marking the cingulum, are deeply branched. In the Upper Cenomanian particularly, the cingular processes, each reflecting a cingular plate, may be completely subdivided. Thus there appears to be two instead of one cingular process for each plate. The presence of an apical archaeopyle and the distinctive deeply furcate cingular processes make orientation of this species relatively easy. A number of well preserved specimens were studied and from the positions of the intratabular processes the reflected tabulation appeared to be 4', 6'', 6c, 6''', 1p, 3''''. The test of the original dinoflagellate is tentatively reconstructed in the accompanying figure (Text-fig. 41). The reflected tabulation of S. longifurcatum is the same as in S. cribrotubiferum (Sarjeant, 1960); however, the latter possesses characteristically perforate processes.
Dimensions: Figured specimens: diameter of central body 32 by 37 µm, length processes 20-24 µm. Range, lateral view: diameter of central body 30-47 µm; apical view: diameter of central body 36-50 µm; length of processes 14-29 µm. Mean diameter of archaeopyle, 20 µm. Number of specimens measured, 24.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Acritarch), thirdly (and now) Surculosphaeridium, fourthly Surculosphaeridium?. Questionable assignment: Stover and Evitt (1978, p.83) — however, Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.517) considered that this species should be assigned to Surculosphaeridium without question.
Holotype: Firtion, 1952, pl.9, fig.1; lost according to Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.517).
Neotype: Foucher, 1976, pl.5, figs.7–8, designated by Fauconnier and Pourtoy in Fauconnier and Masure (2004, p.518); Fauconnier and Masure, 2004, pl.74, figs.2–3.
Locus typicus: Nouvion-en-ThiÚrache, France
Stratum typicum: Cenomanian
Translation, Firton: LPP
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Surculosphaeridium longifurcatum (Firtion, 1952) Davey et al., 1966. From Davey et al. (1966). Central body subspherical. Periphragm smooth with about 26 processes in a complete specimen. Processes closed distally and rather variable, being simple, lobate, foliate or digitate. Some of the processes, especially on the cingulum, are deeply notched. Sometimes there appear to be two cingular processes. Tabulation given as 4', 6", 6c, 6"’, 1p, 3"”. Archeopyle apical, type (tA). Size: type material, central body diameter 40.6 µm, processes 20.4 µm.
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Original description: Firtion, p. 157-158: Hystrichospaeridium longifurcatum.
In this species, the pale body is globular. It differs from H. multifurcatum Deflandre by its longer processes and deeper bifurcations.
Emended description: Davey et al., 1966, p. 163-164
The central body is subspherical. The periphragm is smooth and gives rise to a more or less constant 26 processes in a complete specimen. An angular archaeopyle is commonly present, the detached apical region bearing 4 apical processes. The processes are closed distally and are rather variable in form, being simple, lobate foliate or digitate. Some of the processes, particularly those marking the cingulum, are deeply branched. In the Upper Cenomanian particularly, the cingular processes, each reflecting a cingular plate, may be completely subdivided. Thus there appears to be two instead of one cingular process for each plate. The presence of an apical archaeopyle and the distinctive deeply furcate cingular processes make orientation of this species relatively easy. A number of well preserved specimens were studied and from the positions of the intratabular processes the reflected tabulation appeared to be 4', 6'', 6c, 6''', 1p, 3''''. The test of the original dinoflagellate is tentatively reconstructed in the accompanying figure (Text-fig. 41). The reflected tabulation of S. longifurcatum is the same as in S. cribrotubiferum (Sarjeant, 1960); however, the latter possesses characteristically perforate processes.
Dimensions: Figured specimens: diameter of central body 32 by 37 µm, length processes 20-24 µm. Range, lateral view: diameter of central body 30-47 µm; apical view: diameter of central body 36-50 µm; length of processes 14-29 µm. Mean diameter of archaeopyle, 20 µm. Number of specimens measured, 24.