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Vectensia
From Williams et al., 2017:
[Vectensia, Batten and Lister, 1988, p. 348–349
Type species: Vectensia varians, Batten and Lister, 1988 (fig.3c)]
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Original description: [Batten and Lister, 1988]:
Diagnosis:
Small, spherical to subspherical cyst. Wall two-layered, consisting of a finely granulate, perforate or sometimes microreticulate endophragm. Periphragm thin, membraneous, sometimes only partially developed; may be closely adpressed to endocyst or separated by a narrow pericoel, frequently forming crest-like folds at apex, antapex, and bordering parasulcal area, occasionally with associated fine reticulation; typically also bears simple ridges which delineate circular to subpolygonal fields.
Archeopyle type (tA) or (tAtI), operculum usually adherent, possibly adnate. Margin of archeopyle angular, sometimes with accessory sutures indicating precingular paraplates and a parasulcal notch.
Affinities:
The variable morphology of the periphragm is unknown in any previously described taxa; hence the decision to erect a new genus. Vectensia resembles Cassiculosphaeridia to some extent but lacks the complex reticulate network of crests on the periphragm of that form.
[Vectensia, Batten and Lister, 1988, p. 348–349
Type species: Vectensia varians, Batten and Lister, 1988 (fig.3c)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Batten and Lister, 1988]:
Diagnosis:
Small, spherical to subspherical cyst. Wall two-layered, consisting of a finely granulate, perforate or sometimes microreticulate endophragm. Periphragm thin, membraneous, sometimes only partially developed; may be closely adpressed to endocyst or separated by a narrow pericoel, frequently forming crest-like folds at apex, antapex, and bordering parasulcal area, occasionally with associated fine reticulation; typically also bears simple ridges which delineate circular to subpolygonal fields.
Archeopyle type (tA) or (tAtI), operculum usually adherent, possibly adnate. Margin of archeopyle angular, sometimes with accessory sutures indicating precingular paraplates and a parasulcal notch.
Affinities:
The variable morphology of the periphragm is unknown in any previously described taxa; hence the decision to erect a new genus. Vectensia resembles Cassiculosphaeridia to some extent but lacks the complex reticulate network of crests on the periphragm of that form.