Middle Cenomanian coral fauna from the Roßsteinalmen (Northern Calcareous Alps, Bavaria, Southern Germany) – a revised and extended version
Author
Löser, Hannes
Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Blvd. Luis Donaldo Colosio S / N y Madrid, 83250 Hermosillo, Sonora, Mexico
Author
Werner, Winfried
SNSB – Bayerische Staatssammlung für Paläontologie und Geologie and GeobioCenterLMU, Richard-Wagner-Strasse 10, D- 80333 München, Germany
Author
Darga, Robert
Naturkunde- und Mammut-Museum Siegsdorf, Auenstraße 2, D- 83313 Siegsdorf, Germany
text
Zitteliana
2023
2023-12-20
97
89
147
journal article
10.3897/zitteliana.97.113796
D4564419-3213-4D38-96BB-E7CFE157E0F8
Placoseris
de Fromentel, 1863 b
Type
species.
Placoseris patella
de Fromentel, 1863 b
.
Description.
Solitary cylindric coral. Corallite outline circular or elliptical, centre slightly depressed. Symmetry of septa irregular radial. Synapticulae moderately common. Columella absent or developed as some small elements, presumably trabecular extensions of septal inner margins. Endotheca consists of numerous dissepiments. Wall absent or epithecal.
Remarks.
As already explained in
Löser et al. (2021 b
), in the historic literature the genus
Placoseris
was considered synonymous with
Acrosmilia
d’Orbigny, 1849
.
Acrosmilia
is a conceptual genus; the
type
specimen of the
type
species is available but so poorly preserved that important diagnostic features, such as the presence or absence of pennulae or the amount of septal perforation, cannot be observed. For this reason, the genus
Leptophyllia
Reuss, 1854
was applied (
Löser et al. 2019
) in place of
Acrosmilia
.
Leptophyllia
was for a long time considered to be a junior synonym of
Acrosmilia
. The study of
type
specimens and topotypical material has shown that
Leptophyllia
belongs to the mainly Late Cretaceous family
Synastraeidae
and is restricted to the Late Cretaceous, whereas
Placoseris
belongs to the Jurassic and mainly Lower Cretaceous family
Latomeandridae
.
Leptophyllia
has thicker and less perforate septa, whereas in
Placoseris
the septa are thinner and more perforate at the inner margin. Moreover, the septa are often connected to each other in the latter, a characteristic that is less common in
Leptophyllia
(see
Löser et al. 2019
for details).