Early Jurassic ammonites and belemnites from Huu Nien, Quang Nam area, Central Viet Nam

Liassic ammonites from the Nong Son basin are rare, and little diversified. The fossil record is restricted to two fossiliferous beds. The ammonites display original features with the genera Ectocentrites CE. dommerguesi nov, sp. et E. kherucensis nov. sp.) et Tongdzuyites nov. gen. (T. nongsonensis nov, sp.). These new ammonites are with difficulty correlatable with forms in the literature and moreover their age is not precise; it includes an interval of uncertainty from Early Sinemurian to Early Pliensbachian. For the first time Atractites, associated with the ammonites, is recorded from the Nong Son basin. Worldwide correlations are attempted between the Vietnamese fauna and related taxa.