Nerinea donosa, Gründel & Keupp & Lang & Nützel, 2022

Gruendel, Joachim, Keupp, Helmut, Lang, Fritz & Nuetzel, Alexander, 2022, Late Jurassic (Upper Kimmeridgian) Heterobranchia (Gastropoda) of the coral-facies of Saal near Kelheim and the viciniy of Nattheim (Germany), Zitteliana 96, pp. 179-221 : 179

Nerinea donosa sp. nov.

Plate 5: figs 1-5

2017 - Nerineoidea Nr. 7 - Gründel: 33, pl. 14D.

Derivatio nominis.

Anagram of Latin Nerinea nodosa , referring to the subsutural rows of nodes.

Holotype.

SNSB-BSPG 2021 XV 11, collection Lang.

Locus typicus.

Quarry Saal near Kelheim.

Stratum typicum.

Upper Kimmeridgian.

Paratypes.

Six incomplete or juvenile specimens from Saal: five specimens collection Lang (SNSB-BSPG 2021 XV 10, 13, 168-170), one specimen collection Keupp (SNSB-BSPG 2021 XV 12).

Additional material.

Three specimens without type status from Saal (collection Lang).

Diagnosis.

Shell moderately slender; subsutural row of strong nodes forming distinct ramp; spire gradate; transition from whorl face to base at distinct spiral, crest-like cord; base convex, with narrow umbilicus; aperture with two columellar plaits, one strong parietal and partly a palatal plait; with siphonal canal.

Description.

The largest specimen is 20 mm high. The shell is moderately slender with relatively rapidly increasing whorls. The whorls are more than twice as wide as high. The whorls are ornamented with a subsutural row of strong nodes (8-10 nodes per whorl) occupying 1/2 to 2/3 of whorl height. The nodes demarcate the distinct ramp producing a gradate spire. The suture is accentuated by the ramp. The transition from whorl face to base is marked by a distinct, crest-like spiral cord which is not nodular, and is covered by the following whorls in spire whorls. The incompletely preserved aperture is narrow and has a siphonal canal. It has two columellar plaits, 1-2 parietal plaits and in some specimens a palatal plait. If two columellar plaits are present, the adapical one is weaker as the abapical. The outer lip is not preserved. The base is distinctly convex.

Relationships.

Nerinea mosae Deshayes, 1827 has weaker subsutural nodes and lacks a strong spiral cord at the transition to the base. Nerinea (respectively Ptygmatis ) Phaneroptyxis nogreti Guirand & Ogérien, 1865 has, according to these authors and according to Loriol in Loriol and Bourgeat (1886-1888), a similar shape but is larger and lacks a nodular ornament. Cerithium kelheimense Schlosser, 1882 lacks plaits and a spiral cord at the transition to the base. Itieria (respectively Nerinea ) Phaneroptyxis moreana d’Orbigny sensu Buvignier (1852) and Schlosser (1882) has a higher last whorl in relation to the spire height and it lacks a spiral cord at the transition to the base. Nerinea margaritifera d’Archiac, 1843 and Itieria multicoronata Zittel, 1873) lack a spiral cord at the transition to the base. Nerinea catalloi Gemmellaro, 1870 is broader and stouter and has a higher last whorl in relation to the spire.

Figures

Plate 5. (1 - 5) Nerinea donosa sp. nov. (1) Paratype, SNSB-BSPG 2021 XV 10, Saal (collection Lang), lateral view, height 18 mm. (2 - 4) Holotype, SNSB-BSPG 2021 XV 11, Saal (collection Lang); (2) lateral view, height 8.8 mm; (3) base, width 4.5 mm; (4) last whorl, height 4.5 mm. (5) Paratype, SNSB-BSPG 2021 XV 11, Saal (collection Keupp), lateral view, height 20 mm.