Opis

Despite the wide geographic distribution of the genus, which is especially well
represented in collections from the Table Head Formation of Newfoundland  its relationships remain obscure. Ornamentation and shape of juvenile elements are suggestive of a relationship with cooccurring Lenodus variabilis but there are also some morphologically more primitive conodonts similar to Polonodus, for instance early species of the Pygodus lineage  attributed to Polonodus. Only a single element type has been identified with certainty, although the occurrence of additional types was suggested by BERGSTROM( 1983). LOFGREN ( 1990) proposed a complete apparatus reconstruction with a Lenodlls-like filtratory basket.
The platform elements of Polonodus have a very deep basal cavity and bifurcating processes ornamented with transverse rows of tubercles of variable size. At early ontogenetic stages they are cruciform in occlusal view, later in its ontogeny quite complex shapes may develop.

Type species: Ambalodus clivosus VIIRA, 1974.

Synonimy

Zasięg czasowy

Literatura

Dzik, J. 1994a Conodonts of the Mójcza Limestone. In: J. Dzik, E. Olempska, & A. Pisera. Ordovician carbonate platform of the Holy Cross Mountains. Palaeontologia Polonica 53, 43-128.