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The discovery of Triassic missing links in the Panthalassan domain (Wallowa terrane, U.S.A.) substantiates a direct lineage between internally simple Triassic multichambered aragonitic foraminifers and internally partitioned Jurassic Robertinida. A new hierarchical subdivision is accordingly proposed for the order Robertinida, which is emended to encompass all known post-Paleozoic aragonitic multichambered foraminifers. At the highest taxonomic level, the suborder Robertinina is distinguished from the suborder Duostominina emended to encompass forms without internal structures attached to the aperture, including the planktonic family Favusellidae and the controversial form Pragsoconulus. Two new families (Robertonellidae, Trochosiphoniidae), four new subfamilies (Cassianopapillariinae, Praereinholdellinae, Pragsoconulinae, and Trochosiphoniinae), four new genera (Falsorheinoldella, Praerheinoldella, Robertonella, and Trochosiphonia), and seven new species (Falsorheinoldella ohmi, F. oregonica, Praerheinoldella galei, Robertonella rettorii, R. wallowensis, Trochosiphonia stanleyi, and T. josephi) are introduced. Phylogenetic links between Triassic robertinids, which experienced a rapid diversification during the Triassic, are clarified and their hypothetical long-term relationships with other foraminiferal groups are discussed.

Large benthic agglutinated foraminifers possess subepidermal wall textures similar to the keriothecal textures observed in some Fusulinana. Considering the gap exceeding 50 million years in the record of the first alveolar large agglutinated Mesozoic forms (Textulariana) and their last known Palaeozoic microgranular homologues (Fusulinana), the two groups have been regarded as distinct lineages. The discovery of Wernlina reidae gen. et sp. nov. in Late Triassic carbonate rocks of a Panthalassan terrane questions this assumption. This new form, the earliest unequivocal Mesozoic ‘agglutinated’ alveolar foraminifer, originated from an Endotebidae (Fusulinana). The identification of a Triassic missing link between microgranular and agglutinated foraminifers not only fills the 50 million year gap but also challenges current foraminiferal classification

Early Jurassic aragonitic foraminifers are outstandingly well-preserved in the Marmorea crust, a multiphased ferromanganese layer limiting the Schnöll and Adnet formations (Adnet, Northern Calcareous Alps, Austria