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Horologinella micirugis
From Fensome et al., 2019:
Horologinella micirugis He Chengquan, 1984b, p.163, pl.10, figs.12–14; text-fig.2. Holotype: He Chengquan, 1984b, pl.10, fig.14; Pestchevitskaya, 2001, pl.2, fig.20; Pestchevitskaya, 2003, pl.2, fig.12. Age: Oligocene–Early Miocene (according to Pestchevitskaya, 2001, p.106).
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Original description: [He Chengquan, 1984b] (translated from Chinese with Google):
Horologinella micirugis (sp. nov.)
(Plate X, Figures 12-14; Illustration 2)
The shell is flat, with a quadrilateral to nearly rhomboid outline, slightly constricted at the equatorial region and rounded corners. Each corner bears an annular, membranous protuberance, ranging in size from 8 × 10 to 12.5 × 17.5 microns. The holotype specimen has well-developed and well-preserved protuberances, the largest measuring 17.5 × 20 microns. These protuberances are high, extending 3–5 microns beyond the shell outline. There are two groups of these protuberances, each possibly containing four, perhaps related to the anterior and posterior waist reflective plates. The shell wall is thin, single-layered, and solid, with or without secondary folds. The surface is shortly corrugated to rough, with a finely serrated outline. The ancient mouth is unknown.
The shell is 45-52 microns long, 42-45 microns widest, and 35-40 microns at the narrowest point (equator); the holotype is 51.6 microns long, 45 microns widest, and 38.5 microns narrowest.
Discussion: This new species is morphologically similar to Horologinella spinosigibberosa Brid-eaux et Fisher (1976, p. 22, plate 4, fig. 9; plate 5, figs. 1-16), but the latter has a vermiform, apical protuberance on the annular projection, a paleosteal type. They interpreted these projections as reflecting plates, and the central transverse and longitudinal regions lacking projections as reflecting a girdle and longitudinal groove, respectively. This interpretation also seems to be generally suitable for the present species.
Origin: Shangsi, Guangxi; the second section of the Yongning Group.
Horologinella micirugis He Chengquan, 1984b, p.163, pl.10, figs.12–14; text-fig.2. Holotype: He Chengquan, 1984b, pl.10, fig.14; Pestchevitskaya, 2001, pl.2, fig.20; Pestchevitskaya, 2003, pl.2, fig.12. Age: Oligocene–Early Miocene (according to Pestchevitskaya, 2001, p.106).
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Original description: [He Chengquan, 1984b] (translated from Chinese with Google):
Horologinella micirugis (sp. nov.)
(Plate X, Figures 12-14; Illustration 2)
The shell is flat, with a quadrilateral to nearly rhomboid outline, slightly constricted at the equatorial region and rounded corners. Each corner bears an annular, membranous protuberance, ranging in size from 8 × 10 to 12.5 × 17.5 microns. The holotype specimen has well-developed and well-preserved protuberances, the largest measuring 17.5 × 20 microns. These protuberances are high, extending 3–5 microns beyond the shell outline. There are two groups of these protuberances, each possibly containing four, perhaps related to the anterior and posterior waist reflective plates. The shell wall is thin, single-layered, and solid, with or without secondary folds. The surface is shortly corrugated to rough, with a finely serrated outline. The ancient mouth is unknown.
The shell is 45-52 microns long, 42-45 microns widest, and 35-40 microns at the narrowest point (equator); the holotype is 51.6 microns long, 45 microns widest, and 38.5 microns narrowest.
Discussion: This new species is morphologically similar to Horologinella spinosigibberosa Brid-eaux et Fisher (1976, p. 22, plate 4, fig. 9; plate 5, figs. 1-16), but the latter has a vermiform, apical protuberance on the annular projection, a paleosteal type. They interpreted these projections as reflecting plates, and the central transverse and longitudinal regions lacking projections as reflecting a girdle and longitudinal groove, respectively. This interpretation also seems to be generally suitable for the present species.
Origin: Shangsi, Guangxi; the second section of the Yongning Group.