Cunnolites
Alloiteau, 1952, p. 666
Type Species
Cunnolites barrerei Alloiteau, 1952: 666; Subsequent Designation Alloiteau, 1952: 666
Type Specimen: Holotype; ; Verified; Unknown
Type Locality: Campanian of France.
The holotype of the type species is housed at MNHN (Paris) under R.10944.
Classification
Synonyms
Diagnosis
Solitary, cunnolitid (cupolate), free, circular or elliptical in outline. Base flat to concave. Calicular pit circular or elongate. Septa perforate (younger septa) to subcompact. Columella absent or feebly developed, trabecular. Synapticulae abundant. Endothecal dissepiments thin, sparse. Epitheca present or absent.
Remarks
The validity of the genus Cunnolites has been discussed for about 250 years. Originally, the name Cunnolites was created 'prae-Linnean' by Barrère (1746), and was 'post-Linnean' renamed by Guettard, 1774, as Porpites ellipticus. Lamarck (1801) re-assigned the same specimen again and placed it as the third species in his newly created genus Cyclolites (= Cyclolites ellipticus Lamarck, 1801). Later investigations by Milne Edwards and Haime (1850) revealed that the two species placed before Cyclolites ellipticus, which are Cyclolites numismalis and Cyclolites hemisphaerica, belonged to Palaeozoic forms and had to be excluded from the synonymy of Cyclolites. At the same time they chose Cyclolites ellipticus Lamarck to be the type species of the genus. For priority reasons Alloiteau (1952a, 1957) did not accept the revision by Milne Edwards and Haime (1850). He argued that if the author of a new genus presented more than one species but does not designate a type species then the first species listed had to be acknowledged as the type species. And because in the case of Cyclolites the first species represents the type species of the Palaeozoic taxon Palaeocyclus Milne Edwards and Haime, he denied the validity of the genus Cyclolites and created the taxon Cunnolites. This revision caused confusion in the literature in that some authors started using the new name established by Alloiteau, whereas others kept to the traditional name by Lamarck. The problematic situation was even more complicated by the creation of new genera named Plesiocunnolites Alloiteau, 1957, Plesiocunnolitopsis M. Beauvais, 1964, and Paracunnolites M. Beauvais, 1964. Some authors have accepted these as valid genera, others have ranked them in the subgenus level of Cyclolites or Cunnolites, and still others have put them in synonymy of Cyclolites or Cunnolites. This case can only be resolved by the Commission of Zoological Nomenclature. However, in order to avoid further confusion, the name Cunnolites, based on the type species Cunnolites barrerei Alloiteau, 1957, has been tentatively accepted (Baron-Szabo, 2002) with all the consequences for higher taxonomic levels (e.g. giving the family name of Cunnolitidae Alloiteau, 1952a, priority over Cyclolitidae d'Orbigny, 1851).
Distribution
- Central Europe; Late Jurassic - Paleocene
- Western Europe; Late Jurassic
- Southern Europe; Early Cretaceous - Late Cretaceous
- Eastern Europe; Late Cretaceous
- North Africa; Late Cretaceous
- Central Asia; Late Cretaceous
This page has been in preparation since 02-Jun-2007 12:35
This version was contributed by Rosemarie Baron-Szabo on 14-Sep-2010 20:37.
Page authors are: Rosemarie Baron-Szabo. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Rosemarie Baron-Szabo
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