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Dapsilidinium
From Williams et al., 2017:
[Dapsilidinium, Bujak et al., 1980, p.27-28
Type species: originally as Polysphaeridium pastielsii, Davey and Williams, 1966b (pl.4, fig.10)] ; Dapsilidinium pastielsii, Bujak et al., 1980
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Original description: [Bujak et al., 1980]:
Diagnosis:
Chorate cysts with a subspherical to ovoidal central body bearing numerous processes. Processes intratabular, generally exceeding on per paraplate, mostly uniform in length but sometimes varying slightly in width. Processes hollow, open distally, tubiform, or tapering.
Periphragm ornament smooth, chagrinate, granulate, or spinate, often extending on to the processes.
Archaeopyle apical, tetratabular. Operculum detached.
Affinities:
The genus Polysphaeridium Davey and Williams, 1966, was erected for chorate cysts with numerous tubiform processes and an apical archaeopyle. Davey and Williams designated Polysphaeridium subtile Davey and Williams, 1966, as type of the genus. Eaton (1976, p. 280) stated that the holotype of P. subtile appears to have an epicystal archaeopyle and recommended that the diagnoses of Polysphaeridium and P. subtile should be emended accordingly. Bujak (present study, pl. 3, figs. 9, 12) subsequently examined and photographed the holotype of P. subtile. Although the operculum, which consists of the apical and precingular paraplates, is still attached, principal and accessory archaeopyle sutures are developed and demonstrate that the archaeopyle is epicystal. Topotype material unequivocably confirms that the archaeopyle of this species is epicystal. This has necessitated the present emendation of the genus Polysphaeridium. Species known to have an apical archaeopyle that were previously included in Polysphaeridium are herein transferred to the new genus Dapsilidinium.
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Modified description:
Stover and Williams 1987, p. 69:
Synopsis:
Cysts skolochorate, body subspherical with numerous hollow, nontabular processes of similar size and shape, which are normally open distally; endophragm and periphragm, when discernible, appressed between processes; indications of paratabulation other than archeopyle characteristically lacking; archeopyle apical, type [tA].
Description:
Shape: Body subspherical.
Wall relationships: Undifferentiated autophragm or endophragm and periphragm. Endophragm and periphragm appressed between processes.
Wall features: No parasutural features. Nontabular processes numerous, hollow, similar in size and shape, and normally open distally; process tips typically slightly expanded, rarely branched. Autophragm or periphragm smooth or ornamented with features of low relief.
Archeopyle: Apical, type [tA], principal suture zigzag, but angularity rarely clearly discernible; operculum free.
Paratabulation: Indicated by archeopyle only.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small to large, about 35 µm to nearly 160 µm.
Affinities:
Dapsilidinium differs from Cleistosphaeridium Davey et al. 1966 in having tubiform processes, which are typically open distally rather than closed as in Cleistosphaeridium. Dapsilidinium lacks the single, prominent antapical process possessed by Diphyes Cookson 1965, emended Davey and Williams in Davey et al., 1966.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Dapsilidinium Bujak et al., 1980. Diagnosis, from Bujak et al. (1980, p.27), Chorate cysts with a subspherical to ovoidal central body bearing numerous processes. Processes intratabular, generally exceeding one per paraplate, mostly uniform in length but sometimes varying slightly in width. Processes hollow, open distally, tubiform or tapering. Periphragm ornament smooth, chagrinate, granulate, or spinate, often extending on to the processes. Archeopyle apical, tetratabular. Operculum detached.
[Dapsilidinium, Bujak et al., 1980, p.27-28
Type species: originally as Polysphaeridium pastielsii, Davey and Williams, 1966b (pl.4, fig.10)] ; Dapsilidinium pastielsii, Bujak et al., 1980
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Original description: [Bujak et al., 1980]:
Diagnosis:
Chorate cysts with a subspherical to ovoidal central body bearing numerous processes. Processes intratabular, generally exceeding on per paraplate, mostly uniform in length but sometimes varying slightly in width. Processes hollow, open distally, tubiform, or tapering.
Periphragm ornament smooth, chagrinate, granulate, or spinate, often extending on to the processes.
Archaeopyle apical, tetratabular. Operculum detached.
Affinities:
The genus Polysphaeridium Davey and Williams, 1966, was erected for chorate cysts with numerous tubiform processes and an apical archaeopyle. Davey and Williams designated Polysphaeridium subtile Davey and Williams, 1966, as type of the genus. Eaton (1976, p. 280) stated that the holotype of P. subtile appears to have an epicystal archaeopyle and recommended that the diagnoses of Polysphaeridium and P. subtile should be emended accordingly. Bujak (present study, pl. 3, figs. 9, 12) subsequently examined and photographed the holotype of P. subtile. Although the operculum, which consists of the apical and precingular paraplates, is still attached, principal and accessory archaeopyle sutures are developed and demonstrate that the archaeopyle is epicystal. Topotype material unequivocably confirms that the archaeopyle of this species is epicystal. This has necessitated the present emendation of the genus Polysphaeridium. Species known to have an apical archaeopyle that were previously included in Polysphaeridium are herein transferred to the new genus Dapsilidinium.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Williams 1987, p. 69:
Synopsis:
Cysts skolochorate, body subspherical with numerous hollow, nontabular processes of similar size and shape, which are normally open distally; endophragm and periphragm, when discernible, appressed between processes; indications of paratabulation other than archeopyle characteristically lacking; archeopyle apical, type [tA].
Description:
Shape: Body subspherical.
Wall relationships: Undifferentiated autophragm or endophragm and periphragm. Endophragm and periphragm appressed between processes.
Wall features: No parasutural features. Nontabular processes numerous, hollow, similar in size and shape, and normally open distally; process tips typically slightly expanded, rarely branched. Autophragm or periphragm smooth or ornamented with features of low relief.
Archeopyle: Apical, type [tA], principal suture zigzag, but angularity rarely clearly discernible; operculum free.
Paratabulation: Indicated by archeopyle only.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small to large, about 35 µm to nearly 160 µm.
Affinities:
Dapsilidinium differs from Cleistosphaeridium Davey et al. 1966 in having tubiform processes, which are typically open distally rather than closed as in Cleistosphaeridium. Dapsilidinium lacks the single, prominent antapical process possessed by Diphyes Cookson 1965, emended Davey and Williams in Davey et al., 1966.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Dapsilidinium Bujak et al., 1980. Diagnosis, from Bujak et al. (1980, p.27), Chorate cysts with a subspherical to ovoidal central body bearing numerous processes. Processes intratabular, generally exceeding one per paraplate, mostly uniform in length but sometimes varying slightly in width. Processes hollow, open distally, tubiform or tapering. Periphragm ornament smooth, chagrinate, granulate, or spinate, often extending on to the processes. Archeopyle apical, tetratabular. Operculum detached.