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Cobricosphaeridium
From Williams et al., 2017:
[Cobricosphaeridium, Harland and Sarjeant, 1970, p. 216-217; Emendation: Head et al., 2003, p. 1164–1165, 1167).
Acritarch genus, according to McMinn, 1991; see McMinn et al. (1992, p.316) and Head et al. (2003, p.1161,1163), who considered that this genus may represent copepod eggs
Type species: Cobricosphaeridium hebes, Harland and Sarjeant, 1970 (pl.21, figs.1–2; text-fig.2)]
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Original description: [Harland and Sarjeant, 1970]:
Diagnosis:
Spherical to sub-spherical proximochorate cysts, bearing two distinct process types.
Processes of the first type are relatively long, up to a quarter of the cyst diameter, of very variable form, slender, tapering to cylindrical, erect or sinuous, wart-like, evexate to digitate and foliate, occasionally forked at their tips; bases of processes usually ornamented with granules.
Processes of the second type are short, slender, cylindrical and may also be forked at their distal extremities. These processes are approximately one-half to one-sixth the length of the first type, so that distinguishing between these two process types is always readily possible.
Cingulum and sulcus are present, but not often clearly defined: tabulation is otherwise absent.
Archaeopyle apical (A in terms of the symbols proposed by Evitt, 1967).
Affinities:
This genus is erected to accommodate sub-spherical dinoflagellate cysts that exhibit two distinct process types. One type is conspicuous, the other obvious only under an oil immersion objective. Many of the longer processes appear to be either gonal or intratabular in position, but no overall pattern could be discerned. The processes are solid, do not connect to the interior of the cyst and are closed distally. This genus is similar to Tenua Eisenack emend. Sarjeant in all respects apart from ornamentation; in no case is the simultaneous possession of two distinct process types described from any of the species attributed to the latter genus. Cobricosphaeridium is also similar to Cleistosphaeridium Davey, Downie, Sarjeant and Williams, 1966, but again the distinctive ornamentation and the overall cyst form differentiates the two.
The extent to which the unusual habitat (freshwater sediments) distinguishes this genus can only be surmised at present.
[Cobricosphaeridium, Harland and Sarjeant, 1970, p. 216-217; Emendation: Head et al., 2003, p. 1164–1165, 1167).
Acritarch genus, according to McMinn, 1991; see McMinn et al. (1992, p.316) and Head et al. (2003, p.1161,1163), who considered that this genus may represent copepod eggs
Type species: Cobricosphaeridium hebes, Harland and Sarjeant, 1970 (pl.21, figs.1–2; text-fig.2)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Harland and Sarjeant, 1970]:
Diagnosis:
Spherical to sub-spherical proximochorate cysts, bearing two distinct process types.
Processes of the first type are relatively long, up to a quarter of the cyst diameter, of very variable form, slender, tapering to cylindrical, erect or sinuous, wart-like, evexate to digitate and foliate, occasionally forked at their tips; bases of processes usually ornamented with granules.
Processes of the second type are short, slender, cylindrical and may also be forked at their distal extremities. These processes are approximately one-half to one-sixth the length of the first type, so that distinguishing between these two process types is always readily possible.
Cingulum and sulcus are present, but not often clearly defined: tabulation is otherwise absent.
Archaeopyle apical (A in terms of the symbols proposed by Evitt, 1967).
Affinities:
This genus is erected to accommodate sub-spherical dinoflagellate cysts that exhibit two distinct process types. One type is conspicuous, the other obvious only under an oil immersion objective. Many of the longer processes appear to be either gonal or intratabular in position, but no overall pattern could be discerned. The processes are solid, do not connect to the interior of the cyst and are closed distally. This genus is similar to Tenua Eisenack emend. Sarjeant in all respects apart from ornamentation; in no case is the simultaneous possession of two distinct process types described from any of the species attributed to the latter genus. Cobricosphaeridium is also similar to Cleistosphaeridium Davey, Downie, Sarjeant and Williams, 1966, but again the distinctive ornamentation and the overall cyst form differentiates the two.
The extent to which the unusual habitat (freshwater sediments) distinguishes this genus can only be surmised at present.