Mushrooms are common, conspicuous and morphologically diverse fungi. Most agaricomycete fruiting bodies are ephemeral, so they are extremely rare in fossils. Up to now, all described species of gilled mushrooms, or agaricales, have been known exclusively from amber. Two forms are from the Mesozoic, including the earliest mushrooms, Palaeoagaracites antiquus from 99-million-year-old Burmese amber, and the slightly younger Archaeomarasmius leggetti from New Jersey amber (about 90 million year old). The remaining three species are known from 20-million-year-old early Miocene Dominican amber. Evidence indicating the origin and early diversification of Agaricomycetes is very limited.