Late Jurassic (Upper Kimmeridgian) Heterobranchia (Gastropoda) of the coral-facies of Saal near Kelheim and the viciniy of Nattheim (Germany)
Author
Gruendel, Joachim
Institut fuer Geowissenschaften, Fachrichtung Palaeontologie, Freie Universitaet Berlin, Malteserstrasse 74 - 100, 12249 Berlin, Germany
joachim.gruendel@lingua-pura.de
Author
Keupp, Helmut
Institut fuer Geowissenschaften, Fachrichtung Palaeontologie, Freie Universitaet Berlin, Malteserstrasse 74 - 100, 12249 Berlin, Germany
Author
Lang, Fritz
Drosselweg 16, 96114 Hirschaid, Germany
Author
Nuetzel, Alexander
https://orcid.org/0000-0002-8852-7688
SNSB-Bayerische Staatssammlung fuer Palaeontologie und Geologie, Richard-Wagner-Str. 10, 80333 Muenchen, Germany & Department of Earth and Environmental Sciences, Paleontology and Geobiology, Ludwig-Maximilians-Universitaet Muenchen, Richard-Wagner-Str. 10, 80333 Muenchen, Germany
text
Zitteliana
2022
2022-12-12
96
179
221
http://dx.doi.org/10.3897/zitteliana.96.e84187
journal article
http://dx.doi.org/10.3897/zitteliana.96.e84187
2747-8106-96-179
35B619086E6548B09A177281C2253391
FE0861D71BB454999EE6637C0D9B2B0C
Itieroptygmatis sp. 1
Plate 18: figs 15, 16
Material.
Two juvenile specimens from Saal, collection Lang, SNSB-BSPG 2021 XV 88, 89.
Description.
A specimen is 47 mm high. The shell is moderately high-spired and coeloconoid. At least the first six whorls are moderately slender with whorls increasing slowly in width. The sutures are impressed. The whorls are smooth. The last two preserved whorls increase rapidly in width and at the same time, a furrow-like ramp is forming. The whorl face below the ramp is straight and the transition to the moderately convex base is evenly rounded. The base is smooth and has a wide umbilicus. The aperture is not preserved and it is unknown whether it has plaits.
Remarks.
This incompletely preserved species shows the same ontogenetic change in shell shape as
I. cylindrata
sp. nov. but is distinctly larger.
Relationships.
Itieroptygmatis cylindrata
sp. nov. is considerably smaller and more gracile.
Phaneroptyxis cf. nogreti
sensu
Haegele
(1997)
has whorls that are more regularly increasing in width across the entire shell and lacks a distinct ramp.