Aretz et al_2011.pdf - ORBi - Université de Liège

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Kölner Forum Geol. Paläont., 19 (2011)
M. ARETZ, S. DELCULÉE, J. DENAYER & E. POTY (Eds.)
Abstracts, 11th Symposium on Fossil Cnidaria and Sponges, Liège, August 19-29, 2011
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A new genus of ahermatypic Rugosa from the basal Permian (Asselian) of
Slovenia
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Olga L. KOSSOVAYA 1 , Matevž NOVAK 2 & Dieter WEYER 3
1 All-Russian Geological Research Institute VSEGEI, Srednyy Prospect 74, R-199026 St.Peterburg, Russia;
Olga_Kossovaya@vsegei.ru
2 Geological Survey of Slovenia, Dimičeva ulica, SL-1000 Ljubljana, Slovenie; matevz.novak@geo-zs.si
3 Loewestrasse 15, D-10249 Berlin, Germany; dieter.weyer@t-online.de
Traditionally, aphotic coral communities of cold and deeper waters are named Cyathaxonia facies
(according to HILL (1938: Cyathaxonia fauna). This originally Lower Carboniferous term is in common use
for all such Rugosa faunas (from Ordovician to Permian times) which often are associated also with some
special Tabulata. The name-giving genus Cyathaxonia MICHELIN 1847 (Lower Famennian – Permian) seems
to be well defined, but a partially homoeomorphic, phylogenetically unrelated taxon which sometimes
caused misidentifications was found recently.
The best material of 11 specimens was jointly collected in 2010 in the Dovžanova Soteska section (Devil’s
Gorge) NE of Tržič (Neumarktl in German language literature), Karawanke Mountains of the Southern
Alps, Slovenia, where HERITSCH (1933, 1938) had already described some Rugosa. Our sample comes from
the Dovžanova Soteska Formation of the middle Asselian (Lower Permian, Cisuralian) according to
fusulinid and conodont data (FORKE 2002, NOVAK 2007).
The main diagnostic features of the new genus are a simple septal columella and long contratingent
minor septa. Subtabular sections with a strong stereoplasmatic thickening of all septa seem to be identical
with Cyathaxonia. Lower calicular views differ: there is no circular aseptal columella, genetically derived
from tabulae after an everted growth of a former aulos in the phyletic line Laccophyllum→Cyathaxonia. Here
the axial structure shows clear septal lamellae.
Two additional records of the new genus outside of Slovenia are already available. The first is a
misinterpreted “Cyathaxonia cornu cornu MICHELIN 1847” of FLÜGEL (1972) from the Lower Permian
(Sakmarian?–Artinskian?) basal Jamal Formation of East Iran. The other is an isolated specimen without
precise stratigraphical data (Moscovian–Dzhulfian) from the Bükk Mountains, Hungary.
The classification is somewhat difficult in view of the hitherto few records. Provisionally we propose the
probable development Rotiphyllum HUDSON 1942 → Variaxon FEDOROWSKI 2010 → new genus. This implies
a now no longer monotypic subfamily Variaxoninae FEDOROWSKI 2010 (at least Serpukhovian—Asselian)
within the family Antiphyllidae ILINA 1970 (suborder Zaphrentoidina SCHOUPPÉ & STACUL 1959), whereas
the somewhat homoeomorphic genus Cyathaxonia MICHELIN 1847 is a member of the suborder
Cyathaxoniina SPASSKIY 1977 (family Cyathaxoniidae MILNE-EDWARDS & HAIME 1850, subfamily
Cyathaxoniinae together with their ancestors, the Laccophyllinae GRABAU 1928). Also the enigmatic
Epiphanophyllum ILINA 1970 (Middle Permian, Pamirs) must be compared.
Preliminary data of DE GROOT (1963), RODRÍGUEZ & KULLMANN (1999), and FALCES & RODRÍGUEZ (1994)
might indicate a farther distribution of our new genus in space and time: their Moscovian “Cyathaxonia”
from Spain seem to comprise both aseptal and septal columellar structures. Perhaps, Cyathaxonia degrootae
RODRÍGUEZ 1984 is a member of the new genus. For sure identifications, often neglected studies of the calice
are demanded to see the columella in statu nascendi without later stereoplasmatic thickening and
diagenetic recristallisations.
FEDORWSKI, J. (2010): Some peculiar rugose coral taxa from Upper Serpukhovian strata of the Czech Republic. - Acta
Geologica Polonica, Warszawa, 60 (2): 165-198.
FALCES, S. & RODRÍGUEZ, S. (1994): Microstructura del género Cyathaxonia en el Carbonífero español. - Comunicaciones
de las X Jornadas de Paleontología, Madrid: 67- 69.
FLÜGEL, H. W. (1972): Die paläozoischen Korallenfaunen Ost-Irans. 2. Rugosa und Tabulata der Jamal-Formation
(Darwasian?, Perm). - Jahrbuch der Geologischen Bundesanstalt, 115 (1): 49-102.