Parvulatopsis? sp.

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

Parvulatopsis? sp.

Plate 5 : fig. 16; Plate 6: figs 1, 2

Material.

5 juvenile specimens, SNSB – BSPG 2016 XXI 1759 –1763.

Description.

Shell-broadly turbiniform, egg-shaped, low-spired with rapidly increasing whorls; largest specimen 12 mm wide; smallest specimen 7 mm wide (best preserved one); whorls convex; suture sinks significantly during ontogeny; whorl face ornamented with 5 strong, knobby spiral cords; distances between adapical suture and adapical spiral cord as well as between this and the 2 nd spiral cord particularly wide; this portion of whorl face distinctly oblique; whorl face vertical between 2 nd and 3 rd spiral cords; 4–6 weak spiral cords without nodes between strong spiral cords; growth lines straight, prosocline from adapical suture to center of the base.

Remarks.

Juvenile specimens of Bipartopsis robustus Gründel et al., 2015 are smaller, the distances between the strong spiral cords are approximately the same but overall narrower than in Parvulatopsis ? sp. and the adapical whorl face is not as oblique (in lateral view). Neritopsis jurensis Münster sensu Kuhn (1939) has 3 spiral cords at equal distances on the whorl face and strong axial ribs (according to the description, not visible in Kuhn’s (1939) illustration).

Figures

Plate 5. (1, 2) Creniturbo sp., SNSB – BSPG 2016 XXI 1745, lateral and basal views, width 13 mm. (3, 4) Creniturbo sp., SNSB – BSPG 2016 XXI 1746, collection Lang, (3) detail of base, width 3.2 mm, (4) lateral view, width 3.5 mm. (5–7) Kelheimia triangulata sp. nov., holotype, SNSB – BSPG 2016 XXI 1749, (5, 7) lateral and apical views, width 23 mm, (6) apex in lateral view, height 9 mm. (8–10) Kelheimia triangulata sp. nov., paratype, SNSB – BSPG 2016 XXI 1750, lateral, apical and basal views, width 47 mm. (11) Kelheimia triangulata sp. nov., paratype, SNSB – BSPG 2016 XXI 1751, oblique basal view with aperture, height of aperture 32 mm. (12–15) Vetigastropoda gen. and sp. indet., SNSB – BSPG 2016 XXI 1758, (12, 15) lateral and basal views, width 23 mm, (13) detail of lateral view, width 12 mm, (14) detail of ornament, height 10 mm. (16) Parvulatopsis? sp. 1, SNSB – BSPG 2016 XXI 1759, lateral view, width 12 mm.

Plate 6. (1, 2) Parvulatopsis? sp. 1, SNSB – BSPG 2016 XXI 1759, lateral and apical views, width 12 mm. (3) Neridomus hemisphaerica (Roemer, 1836), SNSB – BSPG 2016 XXI 1764, lateral view, width 33 mm. (4, 5) Neridomus hemisphaerica (Roemer, 1836), SNSB – BSPG 2016 XXI 651, lateral views, height 35 mm. (6, 7) Neridomus hemisphaerica (Roemer, 1836) with color pattern, SNSB – BSPG 2016 XXI 1765, lateral and apical views, width 36 mm. (8–12) Neritopsis? rotundatus sp. nov., holotype, SNSB – BSPG 2016 XXI 1767, (8–10) abapertural, apertural and apical views, width 15 mm, (11) detail in oblique apical view, width 11 mm, (12) basal view, width 15 mm. (13, 14) Wallowiella (Plicaropsis) cancellata (Stahl, 1824) (adult), SNSB – BSPG 2016 XXI 1773, lateral and basal views, width 21 mm.