A new fossil Cedrus species from the early Miocene of northwestern Turkey and its possible affinities

A new fossil species, Cedrus anatolica n. sp., is described from the early Miocene Hançili Formation of Turkey. All analyses were performed on the thin sections housed at Istanbul University – Cerrahpasa. The new species was interpreted as having the closest affinity with the modern Mediterranean species Cedrus atlantica (Endlicher) Manetti ex Carriere and Cedrus libani Richard. The evolutionary line shows some changes in wood anatomy. From the early Cretaceous to the early Miocene, the pits on the tangential walls of the tracheids gradually decreased, the height of rays increased and the number of epithelial cells in the traumatic resin canals increased slightly. These features are similar in three modern species; other wood anatomical features are also quite stable among the new fossil and modern species.     

Fossil roots with root nodules from the Madygen Formation (Ladinian–Carnian; Triassic) of Kyrgyzstan

Documented evidence of root nodules in fossil plants is exceedingly rare, and thus the evolutionary history and paleobiology of these specialized structures hosting symbiotic microorganisms continue to be largely unresolved. Here we report adpression fossils of slender roots from the ~237-million-yr-old Madygen Formation in Kyrgyzstan, to which are laterally attached spheroidal protuberances up to 2.5 mm in diameter that we interpret as root nodules based on spatial arrangement and comparisons with other fossil and extant root nodules, along with several types of other plant structures exhibiting a superficially similar appearance (e.g., fertile organs, rhizome tubers). The producer of the roots and the biological nature and affinities of the microorganisms inhabiting the nodules remain unknown. The Madygen fossils are nevertheless significant because they represent the second-oldest record of root nodules worldwide, predated only by permineralized mycorrhizal root nodules from the Triassic of Antarctica.     

以演化时间为新增指标构建真菌分类系统

随着分子系统发育研究的普及,真菌各分类类群逐渐被修订为单系发生类群,通常结合形态学特征为代表的表型特征（“单系+表型特征”）对不同的分类等级命名是最为普遍的方法。历史上存在的大量多系名称被逐步修订、补充和完善,各个不同等级类群的分类系统变得更加合理、客观和趋于自然,这是分类学进程中巨大的进步。然而系统发育重建所揭示的单系类群并没有相应的标准来对应于纲目科属等种上分类等级,所以并不能直接转换为分类系统,且在分类实践中,由于不同分类学家在决定各个单系类群对应的分类等级时采用的尺度不同、依据不一,严重影响分类系统的科学性和稳定性。随着分子钟分析方法的出现,实现了对现生生物类群演化时间的估算,所以在系统发育、表型特征研究的基础上,把演化时间作为真菌分类的新增指标来划分和命名种上分类等级的方法（“单系+表型特征+演化时间”）得以应用。本文回顾了首次利用这种方法重建蘑菇属分类系统的工作,目前研究所揭示的担子菌门和子囊菌门从门至科各分类等级的演化时间范围,及利用演化时间为新增指标在分类命名中的应用;分析了影响演化时间估算可靠性的关键因素及对策。我们认为在构建分类系统的研究中增加演化时间指标,使新分类系统体现类群进化过程中的时间维度,能更全面反映类群的进化历程,促进分类系统的科学性和稳定性。     

Trace fossils analysis of fluvial to open marine transitional sediments: Example from the Upper Devonian (Geirud Formation), Central Alborz,Iran

This study integrates ichnological and sedimentological data to interpret depositional environments of the mixed siliciclastic-carbonate fluvial to marine sediments of the Geirud Formation (Upper Devonian) in the central Alborz, northern Iran. Lithofacies analysis shows that these sediments are deposited in fluvial, tidal, shoreface, and shelf environments. Fluvial and tidal deposits are characterized by the presence of bi- to multi-directional cross beddings, reverse directional current ripples, low angle cross beddings, and herringbone cross beddings, with a few scattered Skolithos and Palaeophycus. Shoreface sediments, accumulated in a storm-influenced setting, are characterized by a preferentially interface and low diversity Cruziana ichnoassemblage (Rhizocorallium, Thalassinoides, Palaeophycus, Chondrites, and Ophiomorpha). In contrast to the fluvial-tidal assemblage, the storm-influenced shelf sediments display a highly diversified, mixture of dwelling and feeding forms (Arenicolites, Protovirgularia, Diplocraterion, Palaeophycus, Thalassinoides, Chondrites, and Helminthopsis), reflecting the presence of adequate food resources both in substrate and water column under normal salinity conditions. A fluvial-shelf replacement of the weakly to scarcely bioturbated sediments by the Rhizocorallium-Thalassinoides suite (Cruziana) – Chondrites-Helminthopsis (distal Cruziana) suite from the lower to upper parts of the succession clearly indicates an overall deepening upward in the Geirud Formation. In contrast to the lower part, generally of restricted environment, the upper part of the succession mainly shows open marine conditions. Ichnofabric development is controlled primarily by depositional conditions, e.g., bottom water oxygenation, sediment type, food abundance, and hydrodynamic level, which all exert control on substrate colonization style.     

一个不合格发表的新种名——福建双翅龙脑香

杨永康等建立并发表的化石新种福建双翅龙脑香(Diptercoarpus fujianensis Y.K.Yang,H.M.Li et J.K.wu sp.nov.fossil plant)未附任何照片或素描图,且无正规的模式标本登记号和确切的存放单位,与国际植物命名法规中有关古植物的重要条款和规则不符.因此,这个新种名属于不合格发表.     

Angiosperm leaves associated with Sinocarpus infructescences from the Yixian Formation (mid-Early Cretaceous) of NE China

Typical angiosperm dicot leaves are discovered closely associated with reproductive organs of Sinocarpus decussatus from the Yixian Formation, NE China. Leaves are of first rank, small, with fine texture, and with distinct petiole and lamina. Venation pattern is craspedodromous, of at least three discrete orders of veins irregularly arranged. Leaf margin is serrate, with glandular teeth of chloranthoid type. The new Sinocarpus material is better preserved and more complete than the type specimen. It yields support for previous interpretations of reproductive characters and shows that the inflorescences were compound, perhaps combining alternate and opposite phyllotaxis, and that seeds were arranged in two rows, each row with about ten seeds. While these new reproductive characters do not provide further resolution to the systematic assignment of Sinocarpus, the associated leaves, believed to be from the same plant, support previous interpretation of Sinocarpus as a basal eudicot, and particularly close to Ranunculales.     

Normapolles plants: a prominent component of the Cretaceous rosid diversification

The Normapolles complex, characterised by its oblate and triaperturate pollen, constitutes an important and diverse element of many Late Cretaceous and Early Cainozoic floras of the Northern Hemisphere. Based on the dispersed pollen record alone it has been difficult to assess systematic affinities, but relationships with Fagales have been proposed. Over the past twenty years several exquisitely preserved Late Cretaceous reproductive structures with Normapolles type pollen in situ have been described. In this study we provide a summary and new information of these floral structures. Further, a new genus, Dahlgrenianthus, is described from the Late Cretaceous of southern Sweden. The genus includes the type species Dahlgrenianthus suecicus, a number of reproductive structures referred to Dahlgrenianthus sp., and Dahlgrenianthus trigonus (Knobloch et Mai) comb. nov. from the Maastrichtian flora of Walbeck, Germany. Dahlgrenianthus comprises small flowers with pentamerous perianth and androecium and a tricarpellate gynoecium. It is distinguished from all other Normapolles floral structures in its hypogynous floral organisation. All Normapolles floral structures described so far are thought to be related to various members of the core Fagales, but the group is obviously not monophyletic. The stratigraphic range of the Normapolles taxa and other fagalean fossils strongly suggests that all major fagalean lineages were present by the Cenomanian or earlier.     

古昆虫学研究的发展历程简介

古昆虫学研究始于200年前。此后,该学科不断发展,不断提高。依据研究方法及综合水平的不同,可将其发展历程划分为6个部分:朴素的萌芽和学科的诞生、基础分类研究、归纳总结研究、系统发育学研究、古环境古生态及古地理的研究、化石昆虫与其他物种相互作用的研究。文章简要介绍了上述各部分,并作了简评。     

Carbon sources for the Palaeozoic giant fungus Prototaxites inferred from modern analogues

A wide range of carbon isotope values in the Devonian fossil Prototaxites has been interpreted to support heterotrophy and the classification of Prototaxites as a giant fungus. This inference remains controversial because of the huge size of Prototaxites relative to co-occurring terrestrial vegetation and the lack of existing fungal analogues that display equally broad isotopic ranges. Here, we show wide isotopic variability in the modern saprotrophic fungus Arrhenia obscurata collected adjacent to shallow meltwater pools of a sparsely vegetated glacial succession in the Washington Cascades, USA. Soils collected specifically around the edges of these pools were up to 5‰ higher in δ¹³C than adjacent soils consistent with C₃ origin. Microbial sources of primary production appear to cause these high δ¹³C values, and the environment may be analogous to that of the Early Devonian landscapes, where Prototaxites individuals with extreme isotopic variance were found. Carbon isotopes are also compared in Prototaxites, Devonian terrestrial vascular plants, and Devonian algal-derived lake sediments. Prototaxites isotopic values show little correspondence with those of contemporaneous tracheophytes, providing further evidence that non-vascular land plants or aquatic microbes were important contributors to its carbon sources. Thus, a saprotrophic fungal identity is supported for Prototaxites, which may have relied on deposits of algal-derived organic matter in floodplain environments that were less dominated by vascular plants than a straight reading of the macrofossil record might suggest.