Caryomphalus sp.

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

Caryomphalus sp. , cf. concavus Gründel, Keupp & Lang, 2017

Plate 3: figs 2–3

Material.

1 specimen from Saal, SNSB – BSPG 2016 XXI 1717 .

Description.

Shell trochiform; illustrated specimen 14 mm high; whorls weakly convex, evenly expanding; earliest preserved whorl with two nodular spiral cords, one in suprasutural position, other spiral cord between edge and abapical suture; a further spiral cord soon appears above edge; this spiral cord is initially weaker than the other cords but rapidly becomes as strong as other cords; suture somewhat deflected downward on the last part of last whorl, so that another spiral cord becomes exposed on penultimate whorl; edge becomes weaker, and changes to a regular spiral cord on last whorl so that whorl face becomes convex with evenly rounded transition to base; base narrowly phaneromphalous, weakly convex, covered with ca. 10 spiral cords that are somewhat weaker than those on whorl face; all spiral cords bear fine tubercles that are elongated in prosocline direction; details of round aperture not preserved.

Remarks.

In Caryomphalus concavus Gründel, Keupp & Lang, 2017 , the late whorls are more rapidly increasing (more concave flanks of shell); it has axial ribs on the early whorls, and the inner spiral cords on the base are separated by wider interspaces than the outer spiral cords.

Figures

Plate 3. (1) Caryomphalus globatus (Buvignier, 1843), SNSB – BSPG 2016 XXI 1713, lateral view, width 15 mm. (2, 3) Caryomphalus sp., cf. concavus Gründel, Keupp & Lang, 2017, SNSB – BSPG 2017 XXI 1717, lateral and basal views, height 14 mm, width 12 mm. (4) Proconulus? sp. 1 sensu Gründel, Keupp and Lang (2017), SNSB – BSPG 2016 XXI 1718, lateral and basal views, height 11 mm. (5–7) Nododelphinula oblonga sp. nov., holotype, SNSB – BSPG 2016 XXI 1721, lateral views, apertural and abapertural, basal view, width 26 mm. (8–9) Nododelphinula oblonga sp. nov., paratype, SNSB – BSPG 2016 XXI 1930, collection Lang, shell in lateral and dorsal view, width 27 mm. (10–12) Serrettella gerberi (Gründel, Keupp & Lang, 2017), SNSB – BSPG 2016 XXI 1722, lateral, basal views and aperture, width 13 mm. (13) Serrettella gerberi (Gründel, Keupp & Lang, 2017), locality 1985, above coral stock, level 2, SNSB – BSPG 2016 XXI 1723, lateral view, width 9.5 mm. (14, 15) Heliacanthus sp. 1, SNSB – BSPG 2016 XXI 1726, abapertural and apertural lateral views, height 12 mm.