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Inflorescences of Mauldinia (Lauraceae) are described from the middle Cenomanian Pauletian facies of Gard, Languedoc-Roussillon, south-eastern France. This is the first record of the genus from this part of Europe. Mauldinia sp. is described based on peduncles and lateral units. Isolated, slender peduncles show spirally arranged scars or rarely attached lateral units. Isolated lateral units consist of cladode-like structures showing up to seven flower/fruit scars. Some isolated fruits were found associated with peduncles and lateral units. Fruits are ovoid fruits contain a single, elongated seed. The pericarp consists of epicarp, mesocarp and endocarp. The seed consists of two cotyledons containing well-developed reserve cells. Mauldinia sp. from Gard differs from known Mauldinia species by having longer internodes along the peduncle and by the shape of the lateral units. Sedimentological and palaeontological evidence suggests that Mauldinia sp. from Gard grew in a protected, littoral environment with limited marine influence. This report provides new information to the relatively poorly known Cretaceous record of angiosperms in France. The occurrence of Mauldinia in the lower Upper Cretaceous of Gard corroborates the widespread occurrence of the genus in marginal littoral environments during the mid-Cretaceous.  相似文献   
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Alseodaphne changchangensis sp. nov. (Lauraceae), with a perfectly preserved fossil leaf, was found in the Eocene Changchang Formation from the Changchang Basin of Hainan Island, China. This represents the earliest occurrence at the lowest latitude for the genus Alseodaphne, and offers important fossil evidence for further investigation of the origin and evolution of this genus and the paleo-climate of Hainan Island in the Eocene. Based on leaf morphology and cuticle characteristics, our fossil specimen is ...  相似文献   
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为了研究亚热带常绿阔叶林樟科树种的细根化学计量特征,以福建省建瓯市万木林自然保护区天然常绿阔叶林中具有代表性的8种樟科树种(沉水樟Cinnamomum micranthum;浙江桂Cinnamomum chekiangense;黄绒润楠Machilus grijsii;桂北木姜子Litsea subcoriacea;闽楠Phoebe bournei;新木姜子Neolitsea aurata;香樟Cinnamomum camphora;黄毛润楠Machilus chrysotricha)为研究对象,分析细根C、N、P化学计量学特征随序级的变化规律及种间变异情况。结果表明:(1)树种、序级以及二者交互作用对细根C、N、P浓度及C/N、C/P和N/P均具有极显著影响(P<0.01)。(2)随序级增加,大部分树种的细根N和P浓度降低,而C/N和C/P比增大;随序级变化的变异系数C浓度最小,而P浓度最大。(3)不同序级的细根C浓度的种间变异系数均最低,而P浓度的则均最高,N/P比的种间变异系数亦低于C/N比和C/P比;不同序级细根的N、P浓度之间均具有显著的正相关。  相似文献   
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