Kustatscher Evelyn, Falcon-Lang Howard, Lukeneder Alexander
Naturmuseum Südtirol, Bindergasse 1, 39100 Bolzano, Italy.
Department of Earth Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
Cretac Res. 2013 Apr;41:270-276. doi: 10.1016/j.cretres.2013.01.002.
We describe a calcareously permineralised fossil tree-trunk, preserved as driftwood, within hemipelagic sediments of the Cretaceous Puez Formation near Wolkenstein, South Tyrol, Italy. Planktic foraminiferal assemblages recovered from the marls containing the fossil wood indicate a latest middle Albian age. Based on its wood anatomy, the trunk is assigned to and probably has an affinity with the conifer family Araucariaceae. The wood lacks pronounced tree-rings consistent with tree growth within the broad humid tropical belt that existed at that time. The trunk contains cylindrical chambers filled within faecal pellets, demonstrating that oribatid mites infested the tree, either during life, or shortly after death. Prior to final burial, the tree-trunk drifted out into the open sea for a considerable period as indicated by extensive borings assigned to the ichnospecies and produced by teredinid bivalves. Relatively little is known about the Cretaceous floras of Italy, so this new finding fills a gap in our knowledge of the composition and ecology of the vegetation of this region.
我们描述了一棵钙质化石化的树干，它作为漂流木保存在意大利南蒂罗尔州沃尔肯施泰因附近白垩纪普埃兹组的半远洋沉积物中。从含有化石木材的泥灰岩中采集的浮游有孔虫组合表明其年龄为晚阿尔比阶中期。根据其木材解剖结构，该树干被归类于并可能与南洋杉科针叶树有亲缘关系。该木材缺乏明显的年轮，这与当时存在的广阔湿润热带带内树木的生长情况一致。树干内有充满粪便颗粒的圆柱形腔室，表明甲螨在树木活着时或死后不久就对其进行了侵扰。在最终埋葬之前，树干作为漂流木在公海中漂流了相当长一段时间，这一点由归属于遗迹种且由船蛆双壳类动物造成的大量钻孔所表明。人们对意大利白垩纪植物群的了解相对较少，因此这一新发现填补了我们对该地区植被组成和生态认识的空白。
