Carboniferous to Triassic Problematic Fossil Genera

Carboniferous to Triassic Problematic Fossil Genera is a Browse By group of the Nature Atlas that gathers fossil genera from the Carboniferous, Permian and Triassic periods whose biological identity is disputed or unknown, such as Tubiphytes, a marine microfossil of encrusting chambered aggregates that has been debated among sponges, red algae, cyanobacteria and foraminiferans, and Protoavis, a fragmentary Late Triassic genus from Texas first presented as a primitive bird, a claim that has not been widely accepted. An entry belongs here when its own cited article describes a genus from those periods whose classification remains unsettled. It excludes the problematic genera of the Proterozoic, Ediacaran, Cambrian, Ordovician and Devonian, which have groups of their own.