The Paris biota is an exceptionally diverse Early Triassic (approximately 249 million years ago)[1] fossil assemblage described in 2017 from the Lower Shale Member of the Thaynes Group.

[3] The Paris biota was found in layers dating back to the earliest Spathian, a substage of the Olenekian stage of the Early Triassic epoch.

[1] The Paris biota was later also discovered in slightly younger beds in Immigrant Canyon, northeastern Nevada, associated with the ammonoid index fossils Prohungarites sp.

The Paris biota comprises fossils belonging to 20 orders or seven phyla: (1) Retaria (foraminifers)[2] (2) sponges, (3) brachiopods (4) mollusks, (5) arthropods, (6) echinoderms and (7) chordates (vertebrates).

For example, the biota includes leptomitid protomonaxonid sponges, a group that is otherwise known from the early Paleozoic era (e.g. from the Cambrian Burgess Shale of western Canada).