Paleobotany Department, The Swedish Museum of Natural History, Box 50007 SE-104 05 Stockholm, Sweden.
Am J Bot. 2008 Apr;95(4):465-71. doi: 10.3732/ajb.95.4.465.
Seed ferns, dominant elements of the vegetation in many parts of the world from the Triassic to Cretaceous, were considered to have disappeared at the end of the Cretaceous together with several other groups that had occupied key positions in terrestrial and marine ecosystems such as dinosaurs, plesiosaurs, and ammonoids. Seed-fern demise is generally correlated with competition from diversifying flowering plants through the Cretaceous and the global environmental crisis related to the Chicxulub impact event in the paleotropics at the end of the period. New fossils from Tasmania show that one seed-fern lineage survived into the Cenozoic by at least 13 million years. These fossils are described here as a new species, Komlopteris cenozoicus. Komlopteris is a genus of seed ferns attributed to Corystospermaceae and until now was not known from sediments younger than the Early Cretaceous. Discovery of this "Lazarus taxon," together with the presence of a range of other relictual fossil and extant organisms in Tasmania, other southern Gondwanan provinces, and some regions of northern North America and Asia, underscores high-latitude regions as biodiversity refugia during global environmental crises and highlights their importance as sources of postextinction radiations.
种子蕨类植物是世界上许多地区从三叠纪到白垩纪的植被主要组成部分,被认为与其他几个在陆地和海洋生态系统中占据关键位置的群体一起,如恐龙、蛇颈龙和菊石类,在白垩纪末期消失了。种子蕨类植物的消亡通常与多样化的开花植物竞争有关,这种竞争在白垩纪期间一直在进行,同时与与 Chicxulub 撞击事件有关的全球环境危机有关,该事件发生在白垩纪末期的古热带地区。来自塔斯马尼亚的新化石表明,一种种子蕨类植物至少在新生代存活了 1300 万年。这些化石被描述为一个新物种,即 Komlopteris cenozoicus。Komlopteris 是一种种子蕨类植物,属于 Corystospermaceae 科,直到现在,这种科的化石都没有在早白垩世之前的沉积物中被发现过。这种“拉撒路分类单元”的发现,以及在塔斯马尼亚、其他冈瓦纳南部省份以及北美北部和亚洲一些地区存在的一系列其他残余化石和现存生物,突显了高纬度地区在全球环境危机期间是生物多样性的避难所,并强调了它们作为灭绝后辐射源的重要性。