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Areoligera
From Fensome et al., 2019:
Areoligera, Lejeune-Carpentier, 1938a, p.B164.
Emendation: Williams and Downie, 1966c, p.227–228.
Type: Lejeune-Carpentier, 1938a, text-fig.2, as Areoligera senonensis.
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Original description: [Lejeune-Carpentier, 1938]: (Translation: Stover and Evitt, 1978, p. 17-18):
Diagnosis:
The shell is more or less hemispherical, showing a large convex face and another more or less depressed face of more reduced dimensions. This latter does not show in itself any particular ornament; its bordered by a fringe of spiny laminae. On the other face are located large areas, each one encircled by a collarette; these areas are divided into two main groups by a line of much smaller elements forming a girdle. From the small areas as well as from the collarettes arise numerous spines, most of them long and slender, which may unite together at their distal extremity.
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Emended description:
Williams and Downie,1966
Diagnosis:
Chorate cysts with hemispherical central body, convex dorsal side and flat or depressed ventral side. Processes intratabular, on dorsal surface arranged in soleate or annular complexes, on ventral surface in linear or occasionally soleate complexes. Plate 1```` possesses an annular complex.
Cingulum indicated by reduced linear complexes. reflected tabulation of 4`, 6``, 2-4c, 5```, 1p, 1````.
Archaeopyle apical tetratabular.
Well developed sulcal body circular with bilobed antapex.
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Modified description:
Stover and Evitt 1978, p. 17-18:
Synopsis:
Cysts skolochorate, gonyaulacacean; body lenticular with complexly branched, more or less arculate, penitabular process groups and with rectilinear process groups; midventral and middorsal surfaces consistently free of processes or with processes reduced in size and number; archeopyle apical, Type tA; parasutural notch offset.
Description:
Shape: Body lenticular; one to three local convexities corresponding to an apical and one or two antapical lobations may be present.
Wall relationships: Generally autophragm only; occasionally periphragm and endophragm discernible.
Wall features: No parasutural features. Penitabular processes, which arise from low ridges, form more or less arcuate to rectilinear distally branched process groups; tips of some adjacent process groups may be connected by trabeculae but lack network of ectophragmal trabecalae. Processes on the midventral and middorsal surfaces reduced in size and number, or they may be lacking altogether. Autophragm between processes smooth or faintly ornamented.
Paratabulation: Indicated by penitabular process groups and expressed best at bases of process groups; gonyaulacacean, process formula: 4`, 6``, 0 or 3-6c, 5-6```, 1p, 1````; complete paratabulation rarely expressed.
Archeopyle: Apical, Type tA; pricipal archeopyle suture zigzag; parasulcal notch offset; operculum free.
Paracingulum: Indicated by the absence of processes, or by three to six rectilinear process groups.
Parasulcus: Generally not delimited, position of apical end indicated by offset parasulcal notch.
Size: Intermediate to large.
Affinities:
Areoligera differs from Glaphyrocysta in lacking intricate network of distal trabeculae between process complexes, although a few adjacent process complexes (usually those on the ventral surface) may be joined occasionally by trabeculae. Areoligera differs from Systematophora in having the processes on the midventral and middorsal surface reduced in size and number, or lacking altogether, and in being lenticular rather than subspherical.
Areoligera, Lejeune-Carpentier, 1938a, p.B164.
Emendation: Williams and Downie, 1966c, p.227–228.
Type: Lejeune-Carpentier, 1938a, text-fig.2, as Areoligera senonensis.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Lejeune-Carpentier, 1938]: (Translation: Stover and Evitt, 1978, p. 17-18):
Diagnosis:
The shell is more or less hemispherical, showing a large convex face and another more or less depressed face of more reduced dimensions. This latter does not show in itself any particular ornament; its bordered by a fringe of spiny laminae. On the other face are located large areas, each one encircled by a collarette; these areas are divided into two main groups by a line of much smaller elements forming a girdle. From the small areas as well as from the collarettes arise numerous spines, most of them long and slender, which may unite together at their distal extremity.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Williams and Downie,1966
Diagnosis:
Chorate cysts with hemispherical central body, convex dorsal side and flat or depressed ventral side. Processes intratabular, on dorsal surface arranged in soleate or annular complexes, on ventral surface in linear or occasionally soleate complexes. Plate 1```` possesses an annular complex.
Cingulum indicated by reduced linear complexes. reflected tabulation of 4`, 6``, 2-4c, 5```, 1p, 1````.
Archaeopyle apical tetratabular.
Well developed sulcal body circular with bilobed antapex.
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Modified description:
Stover and Evitt 1978, p. 17-18:
Synopsis:
Cysts skolochorate, gonyaulacacean; body lenticular with complexly branched, more or less arculate, penitabular process groups and with rectilinear process groups; midventral and middorsal surfaces consistently free of processes or with processes reduced in size and number; archeopyle apical, Type tA; parasutural notch offset.
Description:
Shape: Body lenticular; one to three local convexities corresponding to an apical and one or two antapical lobations may be present.
Wall relationships: Generally autophragm only; occasionally periphragm and endophragm discernible.
Wall features: No parasutural features. Penitabular processes, which arise from low ridges, form more or less arcuate to rectilinear distally branched process groups; tips of some adjacent process groups may be connected by trabeculae but lack network of ectophragmal trabecalae. Processes on the midventral and middorsal surfaces reduced in size and number, or they may be lacking altogether. Autophragm between processes smooth or faintly ornamented.
Paratabulation: Indicated by penitabular process groups and expressed best at bases of process groups; gonyaulacacean, process formula: 4`, 6``, 0 or 3-6c, 5-6```, 1p, 1````; complete paratabulation rarely expressed.
Archeopyle: Apical, Type tA; pricipal archeopyle suture zigzag; parasulcal notch offset; operculum free.
Paracingulum: Indicated by the absence of processes, or by three to six rectilinear process groups.
Parasulcus: Generally not delimited, position of apical end indicated by offset parasulcal notch.
Size: Intermediate to large.
Affinities:
Areoligera differs from Glaphyrocysta in lacking intricate network of distal trabeculae between process complexes, although a few adjacent process complexes (usually those on the ventral surface) may be joined occasionally by trabeculae. Areoligera differs from Systematophora in having the processes on the midventral and middorsal surface reduced in size and number, or lacking altogether, and in being lenticular rather than subspherical.