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Kilwacysta
From Fensome et al., 2019:
Kilwacysta, Schrank, 2005, p.62. Type: Schrank, 2005, pl.6, figs.2,4, as Kilwacysta semiseptata.
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Original description: [Schrank, 2005]:
Diagnosis:
Skolochorate dinoflagellate cysts with an ellipsoidal central body and an apical archeopyle that may be accompanied by six accessory archeopyle sutures. Six precingular and five to six postcingular process complexes arise from arcuate, septate ridges; a cingular process series is absent. Major process complexes are wide and membraneous. They may be strongly expanded and deeply furcate or spinose distally. Branching may occur at various levels. The antapical process complex is characterized by a tubiform base or a shallow annulate, septate ridge.
Discussion/Affinities:
Kilwacysta is a genus transitional in morphology between certain species of Systematophora Klement (1960) and Oligosphaeridium Davey and Williams (1966). It shares the pre- and postcingular process complexes arising from arcuate ridges with Systematophora! daveyi Riding and Thomas 1988 (questionably placed in Systematophora by Stancliffe and Sarjeant, 1990) and Systematophorapalmula Davey 1982. It is distinguished from these and other species of Systematophora by the absence of a cingular process series. The type species of Systematophora, Systematophora areolata Klement 1960 and several other species (e.g. Systematophora orbifera Klement 1960, Systematophora penicillata (Ehrenberg 1843) Sarjeant 1980 and Systematophora valensii (Sarjeant 1960) Sarjeant 1961) are also different because of their annulate process complexes (Brenner, 1988). Oligosphaeridium (see emended diagnosis by Davey, 1982) is similar to Kilwacysta in the arrangement of the major processes and the absence of a cingular process series, but it is different because of its basically tubiform processes.
Kilwacysta, Schrank, 2005, p.62. Type: Schrank, 2005, pl.6, figs.2,4, as Kilwacysta semiseptata.
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Original description: [Schrank, 2005]:
Diagnosis:
Skolochorate dinoflagellate cysts with an ellipsoidal central body and an apical archeopyle that may be accompanied by six accessory archeopyle sutures. Six precingular and five to six postcingular process complexes arise from arcuate, septate ridges; a cingular process series is absent. Major process complexes are wide and membraneous. They may be strongly expanded and deeply furcate or spinose distally. Branching may occur at various levels. The antapical process complex is characterized by a tubiform base or a shallow annulate, septate ridge.
Discussion/Affinities:
Kilwacysta is a genus transitional in morphology between certain species of Systematophora Klement (1960) and Oligosphaeridium Davey and Williams (1966). It shares the pre- and postcingular process complexes arising from arcuate ridges with Systematophora! daveyi Riding and Thomas 1988 (questionably placed in Systematophora by Stancliffe and Sarjeant, 1990) and Systematophorapalmula Davey 1982. It is distinguished from these and other species of Systematophora by the absence of a cingular process series. The type species of Systematophora, Systematophora areolata Klement 1960 and several other species (e.g. Systematophora orbifera Klement 1960, Systematophora penicillata (Ehrenberg 1843) Sarjeant 1980 and Systematophora valensii (Sarjeant 1960) Sarjeant 1961) are also different because of their annulate process complexes (Brenner, 1988). Oligosphaeridium (see emended diagnosis by Davey, 1982) is similar to Kilwacysta in the arrangement of the major processes and the absence of a cingular process series, but it is different because of its basically tubiform processes.