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Vesperopsis glabra

Vesperopsis glabra Qiao Xiuyun et al., 1992; Emendation: Mao Shaozhi et al., 1999, p.150–151.

Taxonomic junior synonyms: Vesperopsis granulata and Australisphaera cruciata, both according to Mao Shaozhi et al. (1999, p.150).

Holotype: Qiao Xiuyun et al., 1992, pl.1, fig.9; Gao Ruiqi et al., 1992b, pl.5, fig.7.
Age: Berriasian-Barremian

Original description (Qiao Xiuyun et al., 1992):

Emendation (Mao Shaozhi et al., 1999):
Intermediate cyst with an apical, an antapical horns and one left precingular and one postcingular horns. The dorsal side is more projected than the ventral side, may form a spherical projection expressed in a discontinuous circular fold after compression. Apical horn broad-based. Antapical horn and right postcingular horns about equal in size and widely divergent each other directing toward different planes. Cyst wall thin and smooth or with sparse granules on its surface.
Remarks: Species Vesperopsis glabra and V. granulate (Qiao et al., 1992) are conspecific, both having one left lateral horn developed and thin autophragm, the only difference, according to the original description, between the two species is ornamentation of the wall surface, V. glabra being smooth and V. granulate being sparsely granular, which is here deemed to represent intraspecific variation. In addition, the holotypes of the two species are from the same sample, therefore such a minor and vague differentiation of the two species makes either stratigraphic not ecologic significance. Qiao et al. (1992, p. 30-31, 35, Pl. I, Figs. 13-15) described a new species Australisphaera cruciate based on three specimens from the same sample yielding V. glabra Qiao et al. & V. granulate Qiao et al. The three specimens turned out to be of lateral view of V. glabra after reexamination and also bear little resemblance to the genus Australisphaera, which according to Davey (1978) has typically a free operculum and a polygonal cyst shape. Australisphaera cruciate Qiao et al 1992 never shows a free operculum thus should be abolished.
Comparison: The species differs from other species of the genus in having a well-developed length precingular horn and absence of or a strongly reduced right precingular horn.
Location and horizon: Taikang county of the Songliao Basin; the Shahezi and Yingchen Formations, Valanginian – Hauterivian.
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