The Jehol biota has produced fossils of plant mega- and microfossils, including the earliest angiosperms, charophytes and dinocysts, snails (gastropods), clams (bivalves), superabundant aquatic arthropods called conchostracans, ostracods, shrimps, insects, spiders, fish, frogs and salamanders, turtles, choristoderes, lizards (squamata), pterosaurs, and dinosaurs including dinobirds, the largest mammals known from the Mesozoic, and a great diversity of birds including the earliest advanced birds, and the smallest and largest birds known from the Mesozoic.