Paleobotany and Palynology Laboratory, Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611-7800 USA;
Am J Bot. 2005 Aug;92(8):1294-310. doi: 10.3732/ajb.92.8.1294.
Welwitschiaceae, a family in the Gnetales, is known today from only one extant species, Welwitschia mirabilis. This species is distributed in the Namibian desert, along the western coast of southern Africa, about 10 km inland from the coast. Very little is known about the fossil record of this family. Lower Cretaceous megafossils of various organs, assigned to Welwitschiaceae, are presented here. These fossils include young stems with paired cotyledons attached (Welwitschiella austroamericana n. gen. et sp.), isolated leaves (Welwitschiophyllum brasiliense n. gen. et sp.), and axes bearing male cones (Welwitschiostrobus murili n. gen. et sp.). They were collected in the Crato Formation, which is dated by palynomorphs and ostracods as Late Aptian (114 to 112 million years ago). These sediments are exposed in the Araripe Basin of northeastern Brazil. This study brings together new information of the megafossil record of Welwitschia-like plants and also reports of pollen said to be similar to that of Welwitschia from Lower Cretaceous sediments.
百岁兰科，属于买麻藤纲，现今仅知有一种活植物，即百岁兰。这种植物分布在纳米比亚沙漠，沿着非洲南部西海岸，距离海岸约 10 公里的内陆。关于这个科的化石记录知之甚少。这里介绍了各种器官的早白垩世大化石，被归入百岁兰科。这些化石包括带有成对子叶的幼茎（新属新种，名为南美 Welwitschia austroamericana）、孤立的叶子（新属新种，名为巴西 Welwitschiophyllum brasiliense）和带有雄球果的轴（新属新种，名为穆利 Welwitschiostrobus murili）。它们是在 Crato 组中采集的，该组的年代由孢粉和介形类动物确定为晚阿普第期（1.14 亿至 1.12 亿年前）。这些沉积物暴露在巴西东北部的 Araripe 盆地中。本研究汇集了关于百岁兰类植物大化石记录的新信息，也报告了来自早白垩世沉积物的据称类似于百岁兰的花粉。
