Back
Montanarocysta

From Williams et al., 2017:

[Montanarocysta, Corradini, 1973, p. 183; Emendation: Slimani, 2004, p.177

Type species: Montanarocysta aemiliana, Corradini, 1973 (pl.30, figs.3a–b)]

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Original description: [Corradini, 1973]:

Description:
Dinoflagellate cyst with dorso-flattened central body, subhexagonal in shape, surrounded by a flat membrane, typically irregular in outline. Fibres and processes arising from the central body may sometimes support the membrane itself. Precingular archeopyle.

-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:

Stover and Evitt, 1978, p. 174-175:

Synopsis:
Cyst circumcavate, dorso-ventrally flattened; body subcircular in outline; ectophragm continuous, supported by an unknown number of fibers and tubular or branched processes, of which some are gonal and some are paracingular; archeopyle precingular, Type P (?).

Description:
Shape: In dorsal-ventral view, outline of autocyst subcircular; outline of ectocyst more or less concentric to that of autocyst but with typically irregular margin.
Wall relationships: Cyst circumcavate, dorsoventrally flattened.
Wall features: No parasutural features. Undetermined number of fibers and tubular or branched processes, of which some are gonal and some are paracingular, connect autophragm to ectophragm. Apparently not all processes extend to ectophragm.
Paratabulation: Expression not known.
Archeopyle: Precingular; exact type not given, probably Type P.
Paracingulum: May be indicated by alignment of tubular processes connected proximally by crests.
Parasulcus: No information.
Size: Intermediate to large.

Affinities:
Montanarocysta differs from Thalassiphora in having tubiform processes connecting the wall layers and in being dorso-ventrally flattened. Thalassiphora lacks processes between the wall layers, and most species show no preferred orientation.
Feedback/Report bug