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Achomosphaera verdieri
From Fensome et al., 2019:
Achomosphaera verdieri, Below, 1982c, p.3, pl.8, figs.10a–b,11a–c; text-figs.1a–d.
Emendation: Lister and Batten, 1988b, p.32.
Holotype: Below, 1982c, pl.8, figs.11a–c.
NOW Spiculodinium.
Originally Achomosphaera, subsequently (and now) Spiculodinium.
Age: Hauterivian–Albian.
Locus typicus: Tizi, Morocco
Stratum typicum: Albian
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Original description: [Below, 1982, p. 3] (Translation: LPP):
Diagnosis:
Two-layered, sphaeroidal cyst. Periphragm of the central body smooth or finely reticulate. Periphragm of the solid processes smooth. Gonal and sutural processes bifurcate or trifurcate, second order bifurcation possible. From the widened base, the processes taper continuously to the furcation. The precingulare archaeopyle is type P (3'').
Description:
The cyst is sphaeroidal, sometimes weakly pointed apical. Surface of central body finely reticulate, processes smooth. The length of the gonal, parasutural and occasionally intratabular processes vary between 1/6 and 1/3 of the central bodies diameter. One specimen consists of just delicate or stout processes, which are bi- or trifurcate, independent of their position. The number of the parasutural processes varies. If they are rare and getting stouter, close affinities to A. neptunii (Eisenack, 1958) Davey and Williams, 1966 become obvious.
Dimensions:
Holotype: diameter of central body - 62 µm, length of processes - 8-12 µm; range: diameter of the central body 42 - 51 µm, length of processes - 6-15 µm.
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Emended description:
Lister and Batten, 1988, p. 32
Diagnosis:
A two-layered proximochorate to skolochorate dinoflagellate cyst, ovoidal to subspherical in shape, occasionally surmounted by a small apical boss. Periphragm finely granulate to microreticulate bearing numerous, smooth to slightly fibrous processes which are occasionally simple and acuminate but usually bifurcate or trifurcate and sometimes with a secondary bifurcation. Position of processes usually parasutural; rarely, intratabular processes also present.
Archeopyle precingular, type P3".
Dimensions:
Length 48 (51) 55 µm; width, 38 (42) 45 µm; length of processes 5 (12) 20 µm.
Affinities:
The diagnosis is emended to include the presence of simple acuminate processes, illustrated by Below (1982, p.3, text-fig.1d) but not mentioned in his diagnosis. They are generally few in number and intratabular but may be present along one side of the archeopyle margin or bordering the paracingulum. They are most common on cysts that have generally small processes and rare or absent when these are stout.
A few specimens were found which bear a small apical boss and display a large number of intratabular, simple processes, as well as clearly aligned bi- and trifurcate processes. These to some extent resemble Exochosphaeridium.
A. verdieri differs from A. neptunii in not being as large, and in bearing more numerous and smaller processes that are also sometimes intratabular.
Achomosphaera verdieri, Below, 1982c, p.3, pl.8, figs.10a–b,11a–c; text-figs.1a–d.
Emendation: Lister and Batten, 1988b, p.32.
Holotype: Below, 1982c, pl.8, figs.11a–c.
NOW Spiculodinium.
Originally Achomosphaera, subsequently (and now) Spiculodinium.
Age: Hauterivian–Albian.
Locus typicus: Tizi, Morocco
Stratum typicum: Albian
---------------------------------------------------------------------------------------------------
Original description: [Below, 1982, p. 3] (Translation: LPP):
Diagnosis:
Two-layered, sphaeroidal cyst. Periphragm of the central body smooth or finely reticulate. Periphragm of the solid processes smooth. Gonal and sutural processes bifurcate or trifurcate, second order bifurcation possible. From the widened base, the processes taper continuously to the furcation. The precingulare archaeopyle is type P (3'').
Description:
The cyst is sphaeroidal, sometimes weakly pointed apical. Surface of central body finely reticulate, processes smooth. The length of the gonal, parasutural and occasionally intratabular processes vary between 1/6 and 1/3 of the central bodies diameter. One specimen consists of just delicate or stout processes, which are bi- or trifurcate, independent of their position. The number of the parasutural processes varies. If they are rare and getting stouter, close affinities to A. neptunii (Eisenack, 1958) Davey and Williams, 1966 become obvious.
Dimensions:
Holotype: diameter of central body - 62 µm, length of processes - 8-12 µm; range: diameter of the central body 42 - 51 µm, length of processes - 6-15 µm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Lister and Batten, 1988, p. 32
Diagnosis:
A two-layered proximochorate to skolochorate dinoflagellate cyst, ovoidal to subspherical in shape, occasionally surmounted by a small apical boss. Periphragm finely granulate to microreticulate bearing numerous, smooth to slightly fibrous processes which are occasionally simple and acuminate but usually bifurcate or trifurcate and sometimes with a secondary bifurcation. Position of processes usually parasutural; rarely, intratabular processes also present.
Archeopyle precingular, type P3".
Dimensions:
Length 48 (51) 55 µm; width, 38 (42) 45 µm; length of processes 5 (12) 20 µm.
Affinities:
The diagnosis is emended to include the presence of simple acuminate processes, illustrated by Below (1982, p.3, text-fig.1d) but not mentioned in his diagnosis. They are generally few in number and intratabular but may be present along one side of the archeopyle margin or bordering the paracingulum. They are most common on cysts that have generally small processes and rare or absent when these are stout.
A few specimens were found which bear a small apical boss and display a large number of intratabular, simple processes, as well as clearly aligned bi- and trifurcate processes. These to some extent resemble Exochosphaeridium.
A. verdieri differs from A. neptunii in not being as large, and in bearing more numerous and smaller processes that are also sometimes intratabular.