Hayamiella subvaricosa ( Brösamlen, 1909 )

Gründel, Joachim & Nützel, Alexander, 2024, Late Jurassic (Upper Kimmeridgian) gastropods from Saal near Kelheim (Germany, Bavaria), Zitteliana 98, pp. 19-72 : 19-72

Hayamiella subvaricosa ( Brösamlen, 1909)

Plate 7: figs 8–10

1909 Neritopsis subvaricosa n. sp. – Brösamlen: 243, pl. 19, fig. 29.

1997 Neritopsis subvaricosa Broesamlen, 1909 – Hägele: 57, fig. p. 57, upper left, pl. 7, fig. 2.

Material.

4 specimens and a cast of an imprint (imprint not at hand); illustrated specimen SNSB – BSPG 2016 XXI 1777 .

Remarks.

This species was not available for the study of Gründel et al. (2015). Brösamlen (1909) gave an accurate description. In the material at hand, only the illustrated specimen is almost complete. The aperture is rounded with a strongly convex outer lip. The callus is only partially preserved. At least three of the specimens are adults with a width of 16–17 mm. This species differs from the similar Hayamiella semiplicata ( Brösamlen, 1909) by having fewer axial ribs (about 7–8 per whorl) and the axial ribs do not become weaker during late ontogeny.

Figures

Plate 7. (1, 2) Wallowiella (Plicaropsis) cancellata (Stahl, 1824) (juvenile), SNSB – BSPG 2016 XXI 1774, abapertural and apertural views, width 10 mm. (3, 4) Wallowiella (Plicaropsis) compacta Gründel, Keupp & Lang, 2015, SNSB – BSPG 2016 XXI 1775 (collection Lang), lateral and axial views, width 17 mm. (5–7) Wallowiella (Plicaropsis) compacta Gründel, Keupp & Lang, 2015, c SNSB – BSPG 2016 XXI 1776, abapertural and apertural views, width 18 mm. (8–10) Hayamiella subvaricosa (Brösamlen, 1909), SNSB – BSPG 2016 XXI 1777, abapertural, apertural and apical views, width 18 mm. (11, 12) Hayamiella? sp., SNSB – BSPG 2016 XXI 1778, abapertural and apical views, width 11 mm.