Exceedingly Rare Jurassic Bucklandia Cycad Tree Trunk

The cycads are known to be an extremely ancient group of seed plants, and are now recognized as the sister group to all other living seed plants. Fossil cycads are known from the Lower Permian, of China, 270-280 million years ago, and the group is thought to have arisen from within the ancient seed ferns, of the later Palaeozoic, era. Strictly speaking, most fossil cycads are called cycadeoids and are classified scientifically in the order Bennettitales. They are commonly referred to a living fossils.

The cycads widely radiated and spread in the Permian and early Mesozoic, and have since continued as a separate lineage, still extant, and considered to be living fossils. The Jurassic period is sometimes referred to as the 'Age of Cycads'. During the Jurassic, cycads and their kin along with conifers and Ginkgoales dominated the plant kingdom. Fossil cycads are known from Mesozoic deposits on every continent and latitude from Siberia to the Antarctic. This perception of the cycads as dominant plants of the Mesozoic Era is, however, somewhat misplaced, resulting from past confusion of the cycads and a quite separate, now extinct, group known variously as the Cycadeoids or the Bennettitales.

The three extant cycad families are similar to fossils from the early Tertiary, some 50-60 million years ago. There are also about 19 extinct cycad genera known only as fossils, all from the Paleozoic and Mesozoic eras, excluding the form taxa, that is, isolated leaf or stem fossils that are clearly cycads but cannot be placed in a known family or genus.

Coming from the famous Morrison Formation in Utah, this enormous an exceedingly rare cycad fossil trunk is of the genus Bucklandia and dates to the Jurassic. Climates of Jurassic Utah were mild and moist, as attested by the rich fossil record of the Morrison Formation from where this cycad fossil comes. Plant and dinosaurs fossils are typically found in the Morrison Formation, including Cycads, ginkgoes, conifers, horsetails and Allosaurus, Camptosaurus, Stegosaurus, and Camarasaurus.

The Jurassic Period is sometimes called the "Age of Cycads" because they were so common then. Cycads probably were eaten by some of the herbivorous dinosaurs. Petrified cycads are commonly found in the same rocks with dinosaur bones.