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Coral from the Campanian St. Bartholomä formation, Styria, Austria (Gosau group, Eastern Alps)
FranzBernhard posted a topic in Fossil ID
Hello, some of you may have noticed my rudist posts from the Gosau basin of Kainach - St. Bartholomä, Styria, Austria. Beside rudists, there are also other fossils, but they are much rarer. During my hunting trips in the Campanian St. Bartholomä formation, I have found ca. 300 rudist specimens (hippuritidae and radiolitidae), but only 12 coral colonies, including two imprints, and no individual coral. I would like to show you one of these coral colonies and would like to ask you for your opinion. I will start with the simplest one. In the literature, only one coral species is described and two others are mentioned (without description) from St. Bartholomä. No pictures are published of any of these three coral species. Here is the only existing description of a coral from this formation (Schmidt, 1908): „Ein halbkugeliger Knollen von 5 cm Durchmesser aus der oberen Hippuritenbank von Kalchberg. Auf einem Anschliff sieht man in der Mitte ein Feld, wo die Kelche senkrecht stehen, am Rand sind sie dem Schliff parallel. … Die Kelche haben einen Durchmesser von 1-1.2 mm. An den Septen sind zwei Zyklen zu je acht Stück vorhanden. Das Säulchen ist punktförmig. Sehr schön ist das Cönenchym, aus unregelmäßig angeordneten Kalzifikationszentren bestehen, ausgebildet." "Half-spherical colonie with 5 cm diameter. ... The corallites have a diameter of 1-1.2 mm. There are 2 septal cycles with 8 septa each. The columella is point-like." He identified this coral as : Astrocoenia orbignyana Milne Edwards & Haime, 1848 According to Baron-Szabo (2014), this is today: Actinastrea orbignyi (Milne Edwards & Haime, 1848) The first two pictures are this species, figured in Baron-Szabo (2014). First scale bar is 10 mm, second one 3 mm. Specimen is from Gosau-Rusbach, Austria. The third picture is my specimen from St. Bartholomä. Its very rough at the outside, but not so bad preserved inside. Sorry, I can not make a better picture. I think it comes close to the description and pictures of Actinastrea orbignyi. What do you think? Thank you very much for your opinion! Franz Bernhard Literature: Baron-Szabo, R. Ch. (2014): Scleractinian Corals from the Cretaceous of the Alps and Northern Dinarides with remarks on related taxa. Abhandlungen der Geologischen Bundesanstalt, 68, 1-296. Schmidt, W. (1908): Die Kreidebildungen der Kainach. Jahrbuch der k.k. geologischen Reichsanstalt, 58, 223-246. -
Apical view of a polished cross section of the right (lower) valve of Hippurites nabresinensis from the St. Bartholomä-Formation of the Gosau basin of Kainach - St. Bartholomä in western Styria, Austria. This species has no L-pillar, the P1-pillar is at ca. 3:00, the P2-pillar at ca. 5:00. The hump at ca. 8:00 is a growth anomaly. At ca. 11:00 and 1:00, the position of both teeth sockets is visible (a hypothetical L-pillar would be between them, see the specimen of H. colliciatus), at ca. 2:00 the position of the posterior muscle. At the upper left, it is intergrown with the fragment of another individual of the same (?) species. For specimens like this, the name H. heritschi was also in use. The specimen is from a large mound of stones, which were removed from the fields during many, many decades. This mound located in the southwerstern part of Kalchberg, southwest of St. Bartholomä (Point 36 in my own documentation).
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Apical view of a polished cross section of a pseudocolonie of three indivuals of Hippurites colliciatus from the St. Bartholomä-Formation of the Gosau basin of Kainach - St. Bartholomä in western Styria, Austria. The pillars (L, P1, P2) are indicated, the L-Piller of this species is only a small hump. Left and right of L, the position of both teeth sockets is visible, left of P1 also the position of the posterior muscle. For specimens like this, the name H. exaratus was also in use. The specimen is from a small scree in a small, abandoned marl quarry, located in the eastern part of Kalchberg, southwest of St. Bartholomä (Point 25 in my own documentation).
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Apical view of a polished cross section of the right (lower) valve of Vaccinites alpinus from the St. Bartholomä Formation of the Gosau basin of Kainach - St. Bartholomä in western Styria, Austria. Typical are the subparallel pillars, all situated in a small area of the rudist. The shell around the L-piller (left one) is missing in this specimen. For specimens like this, the name Hippurites/Vaccinites cornuvaccinum was in use. Study of specimens with preserved upper valve showed that V. cornuvaccinum is restricted to the Coniacian and V. alpinus to the upper Santonian and Campanian (Steuber & Schlüter, 2012). They can not be distinguished with the lower valve alone, but have different upper valves. Hence, identification is (also) based on stratigraphic information (Steuber, 2001: „This species [V. ultimus] was also figured by Kaumanns (1962) from Kainach (Styria) and erroneously assigned to various species of the group of V. cornuvaccinum.“). By the way, V. ultimus is a junior synonym of V. alpinus... (Steuber, 2003). The specimen is from a small scree in a small, abandoned marl quarry, located in the eastern part of Kalchberg, southwest of St. Bartholomä (Point 25 in my own documentation).
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Apical view of a polished cross section of the right (lower) valve of Vaccinites vesiculosus from the St. Bartholomä-Formation of the Gosau basin of Kainach - St. Bartholomä in western Styria, Austria. Typical are the slender L-pillar (at ca. 12:00), the round P1-pillar with a very slender stem (at ca. 2:00) and the spatula-shaped P2-piller, also with very slender steem (at ca. 3:00). For specimens like this, names like Hippurites styriacus und Hippurites carinthiacus were also in use. The specimen is from a small scree in a small, abandoned marl quarry, located in the eastern part of Kalchberg, southwest of St. Bartholomä (Point 25 in my own documentation).