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Phoberocysta
From Williams et al., 2017:
[Phoberocysta, Millioud, 1969, p. 431–432; Emendation: Helby, 1987, p. 307.
Tax. sr. syn.: Muderongia, according to Monteil (1991b, p.470) — however, Poulsen (1996, p.56) retained Phoberocysta.
Tax. jr. syn.: Xenascus, by implication in Davey and Verdier (1971, p.27), who considered the "type species" of Xenascus, Xenascus australensis, to be a taxonomic junior synonym of Phoberocysta (now Xenascus) ceratioides — however, Lentin and Williams (1973, p.143) retained Xenascus.
Type species: originally as Wetzeliella? neocomica, Gocht, 1957 (pl.19, fig.1; text-fig.7)] ; Phoberocysta neocomica, Milliouod, 1969; emend. Helby, 1987
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Original description: [Millioud 1967]:
Diagnosis:
Wall two-layered, inner body ovoid in outline. Periphragm of very variable shape, but basically with a rhomboidal to ovoidal midbody, one apical and one or two lateral horns. Antapex with one eccentrically placed horn, although occasionally with a second very small antapical horn. Cingulum present or absent. Midbody and horns bearing irregularly processes of heterogeneous shape. Archeopyle apical, with well marked indentations.
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Modified description:
Stover and Evitt 1978, p. 74:
Synopsis:
Cysts generally cornucavate; body compressed ceratioid with one apical, two cingular, and one or two antapical horns; periphragm with irregularly distributed processes of variable shape and size; archeopyle apical, Type tA; parasulca; notch offset.
Description:
Shape: Compressed ceratioid, with one apical, two cingular, and two unequally developed antapical horns of which one may have a posteriorly directed distal part lying at an obtuse angle to the proximal part, which is in line with the paracingulum.
Wall relationships: Cysts generally cornucavate or occasionally with a narrow antapical pericoel.
Wall features: Parasutural features commonly absent; faint parasutural alignment of processes may be present. Periphragm ornamented with irregularly distributed processes of variable shape and size; processes - pointed, expanded, or branched distally - are on the body and the horns; endophragm smooth or scabrate.
Paratabulation: Indicated mainly by the the archeopyle, occasionally also by faint parasutural lines or by the distribution of ornamentation; formula unknown.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag with offset parasulcal notch; operculum free.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
Phoberocysta differs from Muderongia in having irregularly distributed processes of various shapes and sizes rather than a smooth or weakly ornamentated peripraghm. The bases of the horns of Xenascus are wider than those of Phoberocysta and extend over an appreciably greater portion of the endocyst. In addition, the two cingular horns of Phoberocysta are similar in size, whereas in Xenascus one horn or two quite unequal horns are present.
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Emended description:
Helby, 1987:
Description:
Shape: Ceratioid, with 1 apical, 2 cingular, and 2 antapical horns, of which 1 may be reduced or absent.
Wall relationships: Cornucavate, or circumcavate with a conspicuous antapical pericoel.
Wall features: Parasutural features commonly present as low ridges, or rarely as septa connecting process bases. Ridges and septa may be arranged penitabularly, particularly in middorsal locations. Processes solid or rarely hollow, gonal, intergonal and occasionally intratabular. Processes may be pointed, expanded at bases and/or distal ends, or branched distally. Endophragm smooth to verrucate.
Archaeopyle: apical, type [tA]. Principal archaeopyle suture zigzag with offset parasulcal notch. Opercululm free.
Paratabulation: Indicated by parasutural or penitabular alignment of processes, by low ridges and occasional low septa, and by the archaeopyle. Formula 4`, 0a, 6``, 6c, 6```, 1p, 1````.
Paracingulum: Indicated by cingular horns, lineation of parasutural processes and often by ridging along boundaries of paraplate series.
Parasulcus: Indicated by offsetting of, paracingulum. Usually sinuous, located on left ventral area of epicyst and midventral on hypocyst. Sulcal paraplate arrangement only rarely evident.
Size: Intermediate to large.
Affinities:
Xenascus resembles Phoberocysta in the predominantly parasutural distribution of the processes, prominent apical and antapical horns and archaeopyle style. Xenascus is distinguished by the single lateral horn and the distinctive ceratioid shape.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phoberocysta Millioud, 1969, emend. Helby, 1987. Phoberocysta has a ceratioid outline with one apical, two cingular and two antapical horns, one of which may be reduced or absent. It is cornucavate or circumcavate, with the pericyst bearing solid or hollow processes, which may be gonal, intergonal or intratabular. Paratabulation, where discernible, is 4`, 0a, 6", 6c, 6```` , 1p, 1```` .The archeopyle is apical, type (tA) with offset sulcal notch. Poulsen (1996) retained this genus, rather than accepting Monteil (1991b), who treated it as a taxonomic junior synonym of Muderongia .
[Phoberocysta, Millioud, 1969, p. 431–432; Emendation: Helby, 1987, p. 307.
Tax. sr. syn.: Muderongia, according to Monteil (1991b, p.470) — however, Poulsen (1996, p.56) retained Phoberocysta.
Tax. jr. syn.: Xenascus, by implication in Davey and Verdier (1971, p.27), who considered the "type species" of Xenascus, Xenascus australensis, to be a taxonomic junior synonym of Phoberocysta (now Xenascus) ceratioides — however, Lentin and Williams (1973, p.143) retained Xenascus.
Type species: originally as Wetzeliella? neocomica, Gocht, 1957 (pl.19, fig.1; text-fig.7)] ; Phoberocysta neocomica, Milliouod, 1969; emend. Helby, 1987
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Millioud 1967]:
Diagnosis:
Wall two-layered, inner body ovoid in outline. Periphragm of very variable shape, but basically with a rhomboidal to ovoidal midbody, one apical and one or two lateral horns. Antapex with one eccentrically placed horn, although occasionally with a second very small antapical horn. Cingulum present or absent. Midbody and horns bearing irregularly processes of heterogeneous shape. Archeopyle apical, with well marked indentations.
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Modified description:
Stover and Evitt 1978, p. 74:
Synopsis:
Cysts generally cornucavate; body compressed ceratioid with one apical, two cingular, and one or two antapical horns; periphragm with irregularly distributed processes of variable shape and size; archeopyle apical, Type tA; parasulca; notch offset.
Description:
Shape: Compressed ceratioid, with one apical, two cingular, and two unequally developed antapical horns of which one may have a posteriorly directed distal part lying at an obtuse angle to the proximal part, which is in line with the paracingulum.
Wall relationships: Cysts generally cornucavate or occasionally with a narrow antapical pericoel.
Wall features: Parasutural features commonly absent; faint parasutural alignment of processes may be present. Periphragm ornamented with irregularly distributed processes of variable shape and size; processes - pointed, expanded, or branched distally - are on the body and the horns; endophragm smooth or scabrate.
Paratabulation: Indicated mainly by the the archeopyle, occasionally also by faint parasutural lines or by the distribution of ornamentation; formula unknown.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag with offset parasulcal notch; operculum free.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
Phoberocysta differs from Muderongia in having irregularly distributed processes of various shapes and sizes rather than a smooth or weakly ornamentated peripraghm. The bases of the horns of Xenascus are wider than those of Phoberocysta and extend over an appreciably greater portion of the endocyst. In addition, the two cingular horns of Phoberocysta are similar in size, whereas in Xenascus one horn or two quite unequal horns are present.
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Emended description:
Helby, 1987:
Description:
Shape: Ceratioid, with 1 apical, 2 cingular, and 2 antapical horns, of which 1 may be reduced or absent.
Wall relationships: Cornucavate, or circumcavate with a conspicuous antapical pericoel.
Wall features: Parasutural features commonly present as low ridges, or rarely as septa connecting process bases. Ridges and septa may be arranged penitabularly, particularly in middorsal locations. Processes solid or rarely hollow, gonal, intergonal and occasionally intratabular. Processes may be pointed, expanded at bases and/or distal ends, or branched distally. Endophragm smooth to verrucate.
Archaeopyle: apical, type [tA]. Principal archaeopyle suture zigzag with offset parasulcal notch. Opercululm free.
Paratabulation: Indicated by parasutural or penitabular alignment of processes, by low ridges and occasional low septa, and by the archaeopyle. Formula 4`, 0a, 6``, 6c, 6```, 1p, 1````.
Paracingulum: Indicated by cingular horns, lineation of parasutural processes and often by ridging along boundaries of paraplate series.
Parasulcus: Indicated by offsetting of, paracingulum. Usually sinuous, located on left ventral area of epicyst and midventral on hypocyst. Sulcal paraplate arrangement only rarely evident.
Size: Intermediate to large.
Affinities:
Xenascus resembles Phoberocysta in the predominantly parasutural distribution of the processes, prominent apical and antapical horns and archaeopyle style. Xenascus is distinguished by the single lateral horn and the distinctive ceratioid shape.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phoberocysta Millioud, 1969, emend. Helby, 1987. Phoberocysta has a ceratioid outline with one apical, two cingular and two antapical horns, one of which may be reduced or absent. It is cornucavate or circumcavate, with the pericyst bearing solid or hollow processes, which may be gonal, intergonal or intratabular. Paratabulation, where discernible, is 4`, 0a, 6", 6c, 6```` , 1p, 1```` .The archeopyle is apical, type (tA) with offset sulcal notch. Poulsen (1996) retained this genus, rather than accepting Monteil (1991b), who treated it as a taxonomic junior synonym of Muderongia .