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Xenascus velimensis
Xenascus velimensis Zitt et al. 1997
Holotype: Zitt et al. 1997: Pl. IV, Figs. I -4, Text-fig. 5.
Locus typicus: Velim, section VII (so called Vaclav depression), sample 9
Stratum typicum: early Turonian
Original diagnosis: Zitt et al., 1997, p. 146-147
Cyst cornucavate, proximate; outline ceralioid. Endocyst ovoidal to subspherical; pericyst forms one antapical, and two unequal lateral horns with wide bases. Apical horn is not preserved in any specimen. Antapical horn is conical. Periphragm bears many irregularly distributed processes and pro- trusions of variable shape and size. Archeopyle apical,Type tA. Endophragm is smooth, periphragm smooth or finely punctate. Parasutural features are generally lacking. Smaller processes are placed near paracingulum. Slightly visible archeopyle suture is angular. Length of the whole body varies from 101 to 110 µm (3 specimens), width from 65 to 70 µm. Thickness of wall 3-6 µm; length of antapical horn 49-56 µm, width 23-25 µm. Length of lateral horn is
ranging from 10 to 12 µm and width from 4 to 12 µm.
Occurrence: So far recorded only from grey sediments (samples 7 and 9) of the Velim section VII.
Remarks: Zitt et al., 1997, p. 147
None of the previously described species of Xenascus resembles this form. Only one specimen of
the new species bears some resemblance to Xenascus perforala (Vozzhenikova 1967) Yun 1981, but has no perforations m its wall. New species include specimens which are markedly longer than wide.
Holotype: Zitt et al. 1997: Pl. IV, Figs. I -4, Text-fig. 5.
Locus typicus: Velim, section VII (so called Vaclav depression), sample 9
Stratum typicum: early Turonian
Original diagnosis: Zitt et al., 1997, p. 146-147
Cyst cornucavate, proximate; outline ceralioid. Endocyst ovoidal to subspherical; pericyst forms one antapical, and two unequal lateral horns with wide bases. Apical horn is not preserved in any specimen. Antapical horn is conical. Periphragm bears many irregularly distributed processes and pro- trusions of variable shape and size. Archeopyle apical,Type tA. Endophragm is smooth, periphragm smooth or finely punctate. Parasutural features are generally lacking. Smaller processes are placed near paracingulum. Slightly visible archeopyle suture is angular. Length of the whole body varies from 101 to 110 µm (3 specimens), width from 65 to 70 µm. Thickness of wall 3-6 µm; length of antapical horn 49-56 µm, width 23-25 µm. Length of lateral horn is
ranging from 10 to 12 µm and width from 4 to 12 µm.
Occurrence: So far recorded only from grey sediments (samples 7 and 9) of the Velim section VII.
Remarks: Zitt et al., 1997, p. 147
None of the previously described species of Xenascus resembles this form. Only one specimen of
the new species bears some resemblance to Xenascus perforala (Vozzhenikova 1967) Yun 1981, but has no perforations m its wall. New species include specimens which are markedly longer than wide.