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Riculacysta pala
Riculacysta? pala Kirsch, 1991
Kirsch, 1991, questionably included this species in Riculacysta.
Holotype: Kirsch, 1991, pl.32, figs.1113; text-figs.61a-c
Age: Maastrichtian
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Original description: [Kirsch, 1991]:
Riculacysta? pala sp. nov.
Plate 32. Figs. 11-13; Plate 33, Figs. 2-4, 7, 8; Figs. 61a-c
Derivatio nominis: from pala, Latin = shovel; named after the shovel-like shape of the reticulated periphragm.
Holotype: Specimen 413.A, EF: N 40/3.
Paratypoids: Specimen 413.A, EF: N 39/4; Specimen 413.A, EF: N 40.
Locus typicus: Gerhartsreiter Graben; Upper Bavaria.
Stratum typicum: Gerhartsreiter Strata: Middle Maastrichtian.
Diagnosis: Two-layered, chorate cyst with a granulated, subspheroidal, lenticular, occasionally antapic bilobate central body and a perforated periphragm extending circumlaterally in a wing-like manner ventrally and antapically. Archaeopyle apical.
Description: These relatively large, chorate cysts are characterized by their antapic bilobate, granulated, thick-walled central body, in addition to their wing-like or amplexate periphragm.
When preserved three-dimensionally, the central body is lenticular to reniform in equatorial view, in a few cases convex dorsally and slightly concave ventrally. This wing-like, amplexate, circumlaterally extending periphragm begins at the archaeopyle margin (anterior) and extends across the antapic.
Description: These relatively large, chorate cysts are characterized by their antapic bilobate, granulated, thick-walled central body.
When preserved three-dimensionally, the central body is lenticular to reniform in equatorial view, in a few cases dorsally convex and ventrally slightly concave. This wing-like, amplexate, circumlaterally extending periphragm begins at the archaeopyle margin (anterior) and extends across the antapic.
Description: The periphragm is also separated dorsally from the central body. It is distally incurved ventrally, reaches its maximum extent in the antapic region, and resembles a shovel in appearance. This membrane also traces the two antapic lobes of different lengths antapically. Short, narrow processes are located basally at the edges of the central body, which merge distally into this broad membrane. In well-preserved specimens, the periphragm is spongy and developed antapic-laterally.
A cingulum is usually absent in these specimens; however, in rare cases, a cingulum may be indicated dorsally by fine sutures. Apical archaeopyle (4A) with secate operculum. The latter is absent in most cases but is clearly characterized by an apical lobe.
Comparison: Riculacysta? pala sp. nov. is morphologically similar to Cyclonephelium expansum CORRADINI 1973, but according to CORRADINI (1973: 162), differs in its fine, non-reticulated periphragm and its distinctly developed cingulum. Furthermore, in some individuals of Riculacysta? pala sp. nov., a separation of the reticulated periphragm from the central body can be observed at the anterior-dorsal archaeopylal margin, which means that this membrane lies closely adjacent to the central body over the dorsal region, extending circumlaterally in a wing-like manner.
Morphological similarities also exist with the species Cyclonephelium semitectum BUJAK 1980, which, however, has a periphragm with large perforations in the antapical region. Furthermore, any "spongiform" connections within the membrane are missing, and it has no dorsal-posterior bulges.
Dimensions: Holotype: Size of the central body (L x W) 58 x 72 μm; total size 128 x 96 μm; membrane height max. 56 μm.
Variation: Size of the central body (without operculum) 48-60 x 60-78 μm; total size 96-110 x 100-125 μm.
Material: 20 specimens.
Occurrence: Bad Adelholzen profile (Pattenau strata); Hang S weir profile, Gerhartsreiter locality (Gerhartsreiter strata); Schellenbach II profile (Hachau strata); Moos-Graben II locality (BMS).
Age: Maastrichtian.
Kirsch, 1991, questionably included this species in Riculacysta.
Holotype: Kirsch, 1991, pl.32, figs.1113; text-figs.61a-c
Age: Maastrichtian
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Kirsch, 1991]:
Riculacysta? pala sp. nov.
Plate 32. Figs. 11-13; Plate 33, Figs. 2-4, 7, 8; Figs. 61a-c
Derivatio nominis: from pala, Latin = shovel; named after the shovel-like shape of the reticulated periphragm.
Holotype: Specimen 413.A, EF: N 40/3.
Paratypoids: Specimen 413.A, EF: N 39/4; Specimen 413.A, EF: N 40.
Locus typicus: Gerhartsreiter Graben; Upper Bavaria.
Stratum typicum: Gerhartsreiter Strata: Middle Maastrichtian.
Diagnosis: Two-layered, chorate cyst with a granulated, subspheroidal, lenticular, occasionally antapic bilobate central body and a perforated periphragm extending circumlaterally in a wing-like manner ventrally and antapically. Archaeopyle apical.
Description: These relatively large, chorate cysts are characterized by their antapic bilobate, granulated, thick-walled central body, in addition to their wing-like or amplexate periphragm.
When preserved three-dimensionally, the central body is lenticular to reniform in equatorial view, in a few cases convex dorsally and slightly concave ventrally. This wing-like, amplexate, circumlaterally extending periphragm begins at the archaeopyle margin (anterior) and extends across the antapic.
Description: These relatively large, chorate cysts are characterized by their antapic bilobate, granulated, thick-walled central body.
When preserved three-dimensionally, the central body is lenticular to reniform in equatorial view, in a few cases dorsally convex and ventrally slightly concave. This wing-like, amplexate, circumlaterally extending periphragm begins at the archaeopyle margin (anterior) and extends across the antapic.
Description: The periphragm is also separated dorsally from the central body. It is distally incurved ventrally, reaches its maximum extent in the antapic region, and resembles a shovel in appearance. This membrane also traces the two antapic lobes of different lengths antapically. Short, narrow processes are located basally at the edges of the central body, which merge distally into this broad membrane. In well-preserved specimens, the periphragm is spongy and developed antapic-laterally.
A cingulum is usually absent in these specimens; however, in rare cases, a cingulum may be indicated dorsally by fine sutures. Apical archaeopyle (4A) with secate operculum. The latter is absent in most cases but is clearly characterized by an apical lobe.
Comparison: Riculacysta? pala sp. nov. is morphologically similar to Cyclonephelium expansum CORRADINI 1973, but according to CORRADINI (1973: 162), differs in its fine, non-reticulated periphragm and its distinctly developed cingulum. Furthermore, in some individuals of Riculacysta? pala sp. nov., a separation of the reticulated periphragm from the central body can be observed at the anterior-dorsal archaeopylal margin, which means that this membrane lies closely adjacent to the central body over the dorsal region, extending circumlaterally in a wing-like manner.
Morphological similarities also exist with the species Cyclonephelium semitectum BUJAK 1980, which, however, has a periphragm with large perforations in the antapical region. Furthermore, any "spongiform" connections within the membrane are missing, and it has no dorsal-posterior bulges.
Dimensions: Holotype: Size of the central body (L x W) 58 x 72 μm; total size 128 x 96 μm; membrane height max. 56 μm.
Variation: Size of the central body (without operculum) 48-60 x 60-78 μm; total size 96-110 x 100-125 μm.
Material: 20 specimens.
Occurrence: Bad Adelholzen profile (Pattenau strata); Hang S weir profile, Gerhartsreiter locality (Gerhartsreiter strata); Schellenbach II profile (Hachau strata); Moos-Graben II locality (BMS).
Age: Maastrichtian.