Heliacanthus, Daque, 1938

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

Heliacanthus ? sp. 2

Plate 4: figs 2–7

Material.

7 specimens, SNSB – BSPG 2016 XXI 1730 –1736.

Description.

Shell broadly trochiform with rapidly expanding whorls and gradate spire; one of the better preserved specimens 20 mm wide; earliest whorls clearly exposed due to rapid sinking of suture; whorls ornamented with spiral cords and axial ribs, with nodular intersections; last whorl with rapidly forming wide, oblique ramp; subsutural row of small tubercles; at least 5 slightly knobby spiral cords on ramp; strong keel delimits ramp; keel with rapidly enlarging tubercles (approximately 9 on the last whorl); whorl face below keel vertical and delimited abapically by second knobby keel; at least two weak knobby spiral cords between two keels; a third, somewhat weaker keel forms border to almost flat base; two weak, knobby spiral cords present between second and third keel; base incompletely preserved, covered with several spiral cords; growth lines approximately straight, prosocline; aperture very large, round.

Remarks.

Turbo (Sarmaticus) stephanophorus Zittel, 1873 is more slender, it has fewer nodes on the keels and on the base, there is only a single nodular spiral cord visible (= bordering spiral cord)

Figures

Plate 4. (1) Heliacanthus sp. 1, SNSB – BSPG 2016 XXI 1726, basal view, width 12 mm. (2–6) Heliacanthus? sp. 2, SNSB – BSPG 2016 XXI 1730, (2, 5) lateral and apical view, width 20 mm, (3) apex in lateral view, height 11 mm, (4) shell detail in lateral view, height 11 mm, (6) detail apical view, width 15 mm. (7) Heliacanthus? sp. 2, SNSB – BSPG 2016 XXI 1731, apertural view, height of aperture 19 mm. (8–11) Nododelphinulidae? gen. and sp. indet., SNSB – BSPG 2016 XXI 1731, (8, 10) lateral and lapical views, width of specimen 17 mm, (9) apex in lateral view, height 10 mm, (11) detail of base, width 14 mm. (12, 13) Creniturbo gibbosus sp. nov. (specimen lost), collection Lang, apical and lateral views. (14, 15) Creniturbo gibbosus sp. nov., holotype, SNSB – BSPG 2016 XXI 1738, (collection Lang), oblique basal and lateral views, width 6.5 mm.