Polazzodus
| Polazzodus Temporal range: Late Cretaceous | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Osteichthyes |
| Subclass: | Actinopterygii |
| Order: | Pycnodontiformes |
| Family: | Pyncnodontidae |
| Genus: | Polazzodus Poyoto-Ariza, 2010 |
| Species | |
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Polazzodus is an extinct pycnodontid from the late Cretaceous (early Santonian) of the Polazzo locality of northeastern Italy. The paleoenvironment of Polazzo was a large marine carbonate platform and shallow internal lagoons formed from rudist reefs. P. coronatus is known from a large number of specimens, many of which were very well preserved.
The new genus Polazzodus was erected based on a number of autapomorphies that distinguished it from similar pycnodontid fish. These include a second dorsal ridge scale (from which the Latin species name, coronatus, is derived), presence of olfactory fenestra on premaxilla, posterodorsal process on cleithrum, and several others. The largest measured recovered specimen was 97 mm (3.8 in), and the smallest was 30 mm (1.2 in), which represented a subadult specimen. Polazzodus, being a low-bodied pycnodont, is most similar morphologically to Pycnodus and Tergestrinia, though its body shape is more oval than these genera.[1]
References
- ↑ Poyoto-Ariza, F. J. (2010). "Polazzodus, gen. nov., a new pycnodont fish from the Late Cretaceous of northeastern Italy". Journal of Vertebrate Paleontology. 30 (3): 650–664. doi:10.1080/02724631003762955.