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The new conodont genusMagnigondolellais recognized based on specimens recovered from the Anisian (Middle Triassic) of British Columbia in Canada, and Nevada in the USA. This new genus encompasses problematic specimens with high carinas, which have recently been collectively referred to asNeogondolellaex gr.regalisMosher. Ten species from North America are herein assigned toMagnigondolellan. gen., including the eight new speciesM.alexanderi,M.cyri,M.julii,M.nebuchadnezzari,M.salomae,M. n. sp. A,M. n. sp. B, andM. n. sp. C, as well as the two existing speciesM.regalis(Mosher) andM.dilacerata(Golding and Orchard). Other species from the Tethys region are also tentatively assigned toMagnigondolellan. gen. Based on published records, the genus appears to range from the Spathian to the upper Anisian in North America. The recognition of eight new species from the Anisian significantly increases the conodont biodiversity of this period, which has previously been regarded as a time of low diversity. Although some of the species included withinMagnigondolellan. sp. have relatively long stratigraphic ranges, many have been identified in both British Columbia and Nevada, and therefore show potential for biostratigraphic correlation on a regional scale.

Eight new species of the conodontNeogondolellaare described from the Anisian (Middle Triassic) of northeastern British Columbia. The subtlety of morphological variation in this conodont genus has hampered biostratigraphical correlation, but large, often independently dated collections have enabled the description ofN.cuneiforme,N.curva,N.hastata,N.dilacerata,N.indicta,N.panlaurentia,N.tenera, andN.vellicatan. spp. Several of these species are widespread, as specimens ofN.curva,N.hastata,N.indicta,N.panlaurentia,N.tenera, andN.vellicataare found in contemporary collections from Nevada, whereasN.panlaurentiahas also been recovered from the Canadian Arctic. This distribution promises to significantly improve correlation among Anisian sections in North America.

Exceptionally well preserved Lower Triassic conodonts from Oman include an array ofNeospathodusspecies, many of which are new. Those from the upper Lower Triassic, or Spathian, are described in conjunction with a restudy of conodont type material from Chios, Greece, and an assessment of contemporary collections from Pakistan and western North America. The taxonomic scope of three key species from Chios,Neospathodus homeri, N. triangularis, andN. gondolelloides, is revised. Seven new species are described from Oman:N. abruptus, N. brevissimus, N. brochus, N. crassatus, N. curtatus, N. pusillus, andN. symmetricus;and one new species,N. clinatus, is described from Pakistan. The alliedIcriospathodus collinsoniis also described from Oman. The occurrence and range ofNeospathodusspecies are presented in the context of the ammonoid succession in the Spathian of North America. BothN. homeriandN. triangularis, as revised, have shorter ranges and are more age diagnostic than previously thought.Neospathodus gondolelloidesis a distinct taxon, and not synonymous withChiosella timorensis.Five informal faunal divisions are identified based onNeospathodusand allied species. In ascending stratigraphic order, these are typified byIcriospathodus collinsoni, Neospathodus homeri, N. triangularis, N. symmetricus, andN. gondolelloides.Oman collections represent three of these faunas, which occur also in theColumbitesthroughProhungarites/Subcolumbitesammonoid beds of western U.S.A.