Natura Croatica, Vol. 17 No. suppl. 2, 2008.
Ostalo
Ammonoids of the Upper Scythian from Muć (Dalmatia, Croatia)
Vladimir Golubić
; Prirodoslovni muzej u Splitu, Poljana kneza Trpimira 3, HR-21000 Split
Sažetak
In the general area of the village of Muć in central Dalmatia, Croatia, two rich collections of Upper Scythian ammonites were collected. The first collection was assembled at the end of the 19th century by Fra Marko Malić, a teacher at the Franciscan High School in Sinj. This collection was deposited in the Naturhistorische Museum, Vienna. This collection was processed taxonomically by Ernst Kittl in 1903, in a monographic paper. Kittl’s taxonomic postulates were later greatly revised, some of them with good reason, some without justification. The present author put together the second collection, although with considerable breaks, during the period 1982-2003. It was deposited in the Natural History Museum in Split. A part was collected earlier. This part, also including material from sites in northern Dalmatia, was donated several years ago to the Geological and Palaeontological Museum in Zagreb. In the meantime, that institution has been merged into the Croatian Natural History Museum of which it is now a department. The large amount of ammonites donated is no problem, for the Muć material deposited in the Natural History Museum in Split is much richer in species and preserved specimens. The new collection was put together in conjunction with biostratigraphic control. The ample fonds of field data enabled a better insight into the diversity of ammonite fauna in the Muć site, as well as taxonomic processing. In the Natural History Museum in Split, the collection contains four thousand four hundred and sixty seven inventoried specimens, of which four thousand two hundred and ninety one are classified, i.e., 4% have remained unclassified. The main life forms (ecotypes) are Tyrolites, Dinarites and Carniolites. Common species are represented with infraspecies forms. There are sixty species in the collection, of which there are thirty one new species, and one additional new subspecies. Two new genera were established: Visovacites in the genus Tirolites and Muchites in the genus Carniolites. As well as that the collection contains a little unique damaged material that suggests the feasibility of searching in the field in biostratigraphically defined fossil fauna for another seventeen species. It is possible to estimate that the collection contains about sixty five species. Depending on the evaluation criteria for unique specimens or groups of a small number of specimens, I obtained two results: sixty and sixty four. Bearing in mind however that rare extreme infraspecies forms appear, and that diagenetic deformations often determine morphological characteristics to a degree it is impossible to ignore, for the moment the number of sixty seems more realistic. About fourteen species are represented with two to four specimens, ten species with from five to ten specimens, 15 with more than 10 specimens, seven with more than a hundred specimens, while the others are only single specimens. The degree of preservation of the fossil material is much better than in similar collections. The new collection has made possible an approximation to a population concept of the research. The species lies at the centre of attention. The biostratigraphic horizons and zones are defined by populations of characteristic species of ammonite. A big problem, that of diagenetically damaged fossils, was settled by the collection of a large amount of material, and a proper preparation procedure. Most of the illustration consists of photographs of two hundred and ninety eight specimens of ammonites and one hundred and sixty diagrams of suture lines.
Ključne riječi
Ammonoids; Lower Scythian; Muć
Hrčak ID:
38682
URI
Datum izdavanja:
31.12.2008.
Posjeta: 1.607 *