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Oligosphaeridium asterigerum
Oligosphaeridium? asterigerum (Gocht, 1959) Davey and Williams, 1969
Originally Hystrichosphaeridium, subsequently (and now) Oligosphaeridium?.
Tax. sr. synonym of Oligosphaeridium vasiformum (Neale and Sarjeant, 1962) Davey and Williams, 1966, according to Duxbury, 1977. McIntyre and Brideaux, 1980, retained Oligosphaeridium vasiformum as a separate species.
At the time of the transfer, Davey and Williams, 1969, questionably included this species in Oligosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Oligosphaeridium.
This combination was not validly published in Davey and Williams, 1966, since these authors did not fully reference the basionym.
Davey and Williams, 1966, questionably included the species in Oligosphaeridium.
Holotype: Gocht, 1959, pl.3, fig.1
Locus typicus: Ruehlertwist, Emsland, NW Germany
Stratum typicum: Hauterivian
Translation Gocht, 1959: LPP
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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.
Oligosphaeridium asterigerum (Gocht, 1959) Davey and Williams, 1969. Diagnosis from Gocht (1959, p.67): Central body spherical, bearing 12-18 slender, tubular processes, which are more or less cylindrical, frequently even narrowed distally ; distally the tubular processes split suddenly into 3-6 very long aculei, which are generally at right angles to the process stem. Smaller irregular processes can occur. O.asterigerum differs from O. complex in the shape of the processes, which are more slender and do not broaden out into a funnel-shaped ending. However, some specimens approach O. complex in structure. Size: overall 83-154 µm. Holotype: main body 51 µm maximum, processes without spines 21-25 µm, spines 10-15 µm.
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Original description: Gocht, 1959, p. 67: Hystrichosphaeridium asterigerum
Diagnosis: Central body spherical, bearing 12 to 18 slender, tubiform appendices. Tubes distally hardly widened, often even slightly narrowed; at their extremes suddenly split into 3 to 6 long thin spines, which mostly stand spread at right angless to the axis-channel. Smaller, irregular processes may occur subsidiary. membrane always delicate and transparent.
Dimensions: Holotype: Main body at most 51 µm, proceses without spines 21 to 15 µm, spines 10-17 µm. Largest total diameter about 116 µm. Other specimens between 83 and 154 µm largest total diameter (generally around 115 µm).
Affinities:
Gocht, 1959, p. 67-68
H. asterigerum differs from H. complex in the form of the processes, the shafts of which are more slender and not funnel-shaped distally. The distal spines are normally hardly widened at the bases and not connected by skinlike extensions. They mostly spring at one height, thus resembling umbrella-frameworks. This architectura principle is also found in H. recurvatum (White) as well as -although less clear- in H. tubiferum; in both species the spines are shorter. single, simple processes, which are disttally hardly or very irregularly split, occur in many of my specimens.
Originally Hystrichosphaeridium, subsequently (and now) Oligosphaeridium?.
Tax. sr. synonym of Oligosphaeridium vasiformum (Neale and Sarjeant, 1962) Davey and Williams, 1966, according to Duxbury, 1977. McIntyre and Brideaux, 1980, retained Oligosphaeridium vasiformum as a separate species.
At the time of the transfer, Davey and Williams, 1969, questionably included this species in Oligosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Oligosphaeridium.
This combination was not validly published in Davey and Williams, 1966, since these authors did not fully reference the basionym.
Davey and Williams, 1966, questionably included the species in Oligosphaeridium.
Holotype: Gocht, 1959, pl.3, fig.1
Locus typicus: Ruehlertwist, Emsland, NW Germany
Stratum typicum: Hauterivian
Translation Gocht, 1959: LPP
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Oligosphaeridium asterigerum (Gocht, 1959) Davey and Williams, 1969. Diagnosis from Gocht (1959, p.67): Central body spherical, bearing 12-18 slender, tubular processes, which are more or less cylindrical, frequently even narrowed distally ; distally the tubular processes split suddenly into 3-6 very long aculei, which are generally at right angles to the process stem. Smaller irregular processes can occur. O.asterigerum differs from O. complex in the shape of the processes, which are more slender and do not broaden out into a funnel-shaped ending. However, some specimens approach O. complex in structure. Size: overall 83-154 µm. Holotype: main body 51 µm maximum, processes without spines 21-25 µm, spines 10-15 µm.
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Original description: Gocht, 1959, p. 67: Hystrichosphaeridium asterigerum
Diagnosis: Central body spherical, bearing 12 to 18 slender, tubiform appendices. Tubes distally hardly widened, often even slightly narrowed; at their extremes suddenly split into 3 to 6 long thin spines, which mostly stand spread at right angless to the axis-channel. Smaller, irregular processes may occur subsidiary. membrane always delicate and transparent.
Dimensions: Holotype: Main body at most 51 µm, proceses without spines 21 to 15 µm, spines 10-17 µm. Largest total diameter about 116 µm. Other specimens between 83 and 154 µm largest total diameter (generally around 115 µm).
Affinities:
Gocht, 1959, p. 67-68
H. asterigerum differs from H. complex in the form of the processes, the shafts of which are more slender and not funnel-shaped distally. The distal spines are normally hardly widened at the bases and not connected by skinlike extensions. They mostly spring at one height, thus resembling umbrella-frameworks. This architectura principle is also found in H. recurvatum (White) as well as -although less clear- in H. tubiferum; in both species the spines are shorter. single, simple processes, which are disttally hardly or very irregularly split, occur in many of my specimens.