Am J Bot. 1998 May;85(5):704.
Permineralized leaves of the Triassic podocarpaceous conifer Notophytum krauselii are described from the Fremouw Formation of Antarctica. The leaves are elongate and apetiolate with 8-12 parallel veins. The adaxial epidermis consists of rows of rectangular to pentagonal cells; the abaxial epidermis is papillate. Longitudinally oriented stomata occur on both surfaces. An adaxial palisade layer is present and auxiliary sclereids are common in the mesophyll. The vascular bundles have a weakly defined sheath and are flanked by transfusion tracheids. Bundles in the basipetal area of the leaf are capped by sclerotic tissue and subtended by resin canals. These leaves are superficially similar to those of the extant podocarp genus Nageia, but probably represent a distinct acquisition of this leaf type within the Podocarpaceae. Notophytum leaves are similar to the common compression fossil Heidiphyllum elongatum and may be closely related or even conspecific. Evidence from Antarctica suggests that Heidiphyllum and the seed cone Telemachus were produced by the same plant, and may be closely related to several other early Mesozoic conifers with multiveined leaves.
本文描述了产自南极洲 Fremouw 组的三叠纪罗汉松科针叶树 Notophytum krauselii 的矿化叶。这些叶子是狭长的，无叶柄，有 8-12 条平行的叶脉。叶的上表皮由矩形到五边形的细胞组成；下表皮具乳突。纵向排列的气孔分布于两面。叶肉中存在一个近轴栅栏组织层，辅助韧皮细胞常见。维管束有一个弱定义的鞘，被转输细胞包围。叶基部区域的维管束由硬化组织覆盖，并由树脂管支撑。这些叶子与现生罗汉松属的叶子表面上相似，但可能代表罗汉松科内这种叶型的独特获得。Notophytum 的叶子与常见的压缩化石 Heidiphyllum elongatum 相似，可能密切相关，甚至是同种。来自南极洲的证据表明，Heidiphyllum 和种子球果 Telemachus 是由同一植物产生的，并且可能与其他几个具有多脉叶的早期中生代针叶树密切相关。
