A review of the evolution, biostratigraphy, provincialism and diversity of M iddle and early L ate T riassic conodonts

The taxonomy, diversity, evolutionary lineages, and stratigraphical distributions ofMiddle and earlyLateTriassic conodonts are reviewed and re‐evaluated. Twenty‐five genera are recognized in theMiddle and earlyLateTriassic, including a new genus cited in open nomenclature. Of these, 24 genera are assigned to two families and seven subfamilies. The familyGondolellidae consists of the subfamiliesCornudininae,Epigondolellinae,Neogondolellinae,Novispathodinae,Paragondolellinae andPseudofurnishiinae. The familyGladigondolellidae is monotypic, consisting of the subfamilyGladigondolellinae. The genusNeostrachanognathusis not assigned to any family or subfamily as its origin is unclear. Conodont provincialism was low in the earlyAnisian, but from the lateAnisian faunistic differences started to increase and became stronger during the earlyLadinian, reaching a peak around the mid‐Ladinian. Provincialism remained strong until the earliestCarnian and changed to an all‐Triassic low in the earlyTuvalian. The provincialism betweenNorthAmerica andTethys rebounded on the specific level during the lateTuvalian. Diversities on generic and specific levels have been established, and two major conodont diversity cycles are recognized: the first ranges from theBithynian (earlyAnisian) to theJulian (late earlyCarnian), and the second is restricted to theTuvalian (lateCarnian).