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Vesperopsis jixianensis
From Fensome et al., 2019:
Vesperopsis jixianensis Wan Chuanbiao et al., 1995, p.57–58,60–61, pl.3, figs.9–10.
Emendation: Mao Shaozhi et al., 1999, p.151.
Holotype: Wan Chuanbiao et al., 1995, pl.3, fig.9; Mao Shaozhi et al., 1999, pl.1, fig.4.
Taxonomic junior synonym: Vesperopsis suibinensis, according to Mao Shaozhi et al. (1999, p.151).
Age: Neocomian.
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Emended description (Mao Shaozhi et al., 1999):
Vesperopsis jixianensis Wan, Yan and Yin 1995, emend. nov.(P1. I, Fig. 4)
Vesperopsis jixianensis Wan, Yan and Yin 1995, p. 57, 60, Pl. III, Figs. 9, 10.
Vesperopsis suibinensis Wan, Yan and Yin 1995, p. 57, 60, PI. III, Figs. 2, 3, 7.
Holotype. — Wan, Yan and Yin 1995, Pl. III, Fig. 9, V.JI-10 1250 m, The Chengzihe Formation.
Emended description: Large cysts with one apical, one antapical, one postcingular and two short precingular horns. Dorso-ventrally weakly compressed. Two spherical projections may develop on ventral surface, sandwiched with a mid-depression, which may indicate the sulcus. Apical horn broad-based and tapering with a rounded distal end. Both of the lateral horns have a broad base, which shrink tremendously and then extend posteriorly to form a pointed distal end. The antapical horn and right postcingular horn are about equal in size but each directing to different planes. Wall thin, its surface ornamented with granules, short spines or incomplete fine reticula. Cingulum and sulcus usually indistinctly expressed,
Remarks and comparison: The only difference between Vesperopsis suibinensis Wan et al. & Vesperopsis jixianensis Wan et al. is the surface ornamentation according to Wan et al. 1995, who stated that the former has a densely granular-microreticulate surface while the latter bears short spines or baculate processes (1.0 —2.0 µm in length). However, re-examination on the original specimens demon¬strated the difficulty in distinguishing one from another since short spines or baculate processes can also be found on the surface of Vesperopsis suibinensis and microreticulate pattern may occur locally on the surface of Vesperopsis jixianensis. In addition, the holotypes of the two species occur in the same sample. We, therefore, merge the two into one species and assigned the original holotype of Vesperopsis jixianensis Wan et al. 1995, a well-preserved specimen as the new holotype. Vesperopsis suibinensis is therefore abolished. The present species differs from other species of the genus in having two short precingular horns extending posteriorly, an antapical horn about equal in size to the right postcingular horn and a granulate-microreticulate wall surface on which may bear sparse short spines or bacula.
Location and horizon: Jixian district of the Songliao Basin, Chengzihe Formation, Hauterivian to Barremian.
Vesperopsis jixianensis Wan Chuanbiao et al., 1995, p.57–58,60–61, pl.3, figs.9–10.
Emendation: Mao Shaozhi et al., 1999, p.151.
Holotype: Wan Chuanbiao et al., 1995, pl.3, fig.9; Mao Shaozhi et al., 1999, pl.1, fig.4.
Taxonomic junior synonym: Vesperopsis suibinensis, according to Mao Shaozhi et al. (1999, p.151).
Age: Neocomian.
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Emended description (Mao Shaozhi et al., 1999):
Vesperopsis jixianensis Wan, Yan and Yin 1995, emend. nov.(P1. I, Fig. 4)
Vesperopsis jixianensis Wan, Yan and Yin 1995, p. 57, 60, Pl. III, Figs. 9, 10.
Vesperopsis suibinensis Wan, Yan and Yin 1995, p. 57, 60, PI. III, Figs. 2, 3, 7.
Holotype. — Wan, Yan and Yin 1995, Pl. III, Fig. 9, V.JI-10 1250 m, The Chengzihe Formation.
Emended description: Large cysts with one apical, one antapical, one postcingular and two short precingular horns. Dorso-ventrally weakly compressed. Two spherical projections may develop on ventral surface, sandwiched with a mid-depression, which may indicate the sulcus. Apical horn broad-based and tapering with a rounded distal end. Both of the lateral horns have a broad base, which shrink tremendously and then extend posteriorly to form a pointed distal end. The antapical horn and right postcingular horn are about equal in size but each directing to different planes. Wall thin, its surface ornamented with granules, short spines or incomplete fine reticula. Cingulum and sulcus usually indistinctly expressed,
Remarks and comparison: The only difference between Vesperopsis suibinensis Wan et al. & Vesperopsis jixianensis Wan et al. is the surface ornamentation according to Wan et al. 1995, who stated that the former has a densely granular-microreticulate surface while the latter bears short spines or baculate processes (1.0 —2.0 µm in length). However, re-examination on the original specimens demon¬strated the difficulty in distinguishing one from another since short spines or baculate processes can also be found on the surface of Vesperopsis suibinensis and microreticulate pattern may occur locally on the surface of Vesperopsis jixianensis. In addition, the holotypes of the two species occur in the same sample. We, therefore, merge the two into one species and assigned the original holotype of Vesperopsis jixianensis Wan et al. 1995, a well-preserved specimen as the new holotype. Vesperopsis suibinensis is therefore abolished. The present species differs from other species of the genus in having two short precingular horns extending posteriorly, an antapical horn about equal in size to the right postcingular horn and a granulate-microreticulate wall surface on which may bear sparse short spines or bacula.
Location and horizon: Jixian district of the Songliao Basin, Chengzihe Formation, Hauterivian to Barremian.