Clidicostigus gen. nov., the first Mesozoic genus of Mastigini (Coleoptera: Staphylinidae: Scydmaeninae) from Cenomanian Burmese amber

The Mastigitae is a small supertribe of ant-like stone beetles that currently includes nine extant and five extinct genera. Extinct taxa are known within tribes Clidicini and Mastigini; the latter with one genus discovered in Baltic amber. For the first time, a Mesozoic genus of the tribe Mastigini is described, Clidicostigus arachnipes Jałoszyński, Brunke and Bai, gen. et sp. nov., from Cenomanian Burmese amber. The new taxon shares an enlarged and spiny scape and pedicel with its extant relatives but has deep elytral grooves and a strongly elongate and asymmetrical maxillary palpomere IV; the beetle has also enormously elongate maxillary palps and legs. The elongation of appendages in combination with only moderately large eyes is postulated to have evolved as an adaptation to running quickly, with tactile and chemical senses predominating over sight. The mode of life of Clidicostigus might have been similar to that of extant Mastigini, especially of particularly slender South African species that run on the ground and climb bushes and trees in search of prey.     

A new extinct genus of Glandulariini with two species from Upper Cretaceous Burmese amber (Coleoptera: Staphylinidae: Scydmaeninae)

The Glandulariini (=Cyrtoscydmini) is today the largest, most species-rich and most diverse tribe of Scydmaeninae comprising over 70% of the extant species of this subfamily. Named genera and species of Glandulariini are known mostly from Miocene to Eocene ambers, with only one, recently described Mesozoic taxon. Here we report the second genus of Glandulariini from Upper Cretaceous Burmese amber, Cenomaniola Jałoszyński and Yamamoto, gen. nov., with two species, C. carinata Jałoszyński and Yamamoto, sp. nov. and C. macrophthalma Jałoszyński and Yamamoto, sp. nov. Cenomaniola shows the general body plan typical of the ‘Euconnus complex’ within Glandulariini, with thick bristles on the sides of head and pronotum, a character conserved for nearly a hundred million years. With the previous discovery of Scydmobisetia Jałoszyński and Yamamoto, two major body forms typical of the extant Glandulariini are already proved to have differentiated in or before the Late Cretaceous. This demonstrates early origins and a long conservation of ‘Euconnus-like’ and ‘Sciacharis/Horaeomorphus-like’ body plan in the currently largest group among Scydmaeninae.     

A new genus of silken-fungus beetle (Coleoptera: Cryptophagidae) from the Spanish Cretaceous amber

The Cretaceous new species and genus Albocryptophagus cantabricus gen. et sp. n. is described based on a fossil specimen from the El Soplao amber deposit (Spain). The new genus is similar to the extant genera Cryptophagus and Micrambe, but differs from them in the transverse pedicel, anterior angles of pronotum, pronotal margin unmodified, pronotal pits absent. Albocryptophagus gen. n. is undoubtedly the most ancient representative for the subfamily Cryptophaginae described up today. Because the saproxylic habits in recent species of the family, a similar behavior is inferred for this new fossil. It is a new example that agrees with the idea that fossil beetles from Mesozoic ambers are characterized by a saproxylic lifestyle.     

Reliable radiocarbon dating of fossil pollen grains: It is truly possible

Radiocarbon dating of fossil pollen concentrates has the potential to reduce limitations for sample selection in chronological studies of sedimentary archives. The recent development of the technology for rapidly preparing highly purified fossil pollen concentrates using a cell sorter makes it realistic to turn this dream into reality. Before utilizing pollen as a material for dating with confidence, however, it is necessary to understand the factors that may affect the result of the measurements, and to establish criteria to assess the reliability of the radiocarbon ages produced. In this study, peat soils which are commercially available in large quantities, and are hence used as our laboratory standard, as well as the varved lacustrine sediments from Lake Suigetsu, which has one of the best terrestrial radiocarbon stratigraphies in the world, were used to assess the accuracy of radiocarbon ages of pollen concentrates and to establish an appropriate protocol for sample preparation. A pollen-rich fraction prepared by a recently proposed combined method of physio-chemical pre-treatment and cell sorter (Yamada et al. 2021) was submitted to a range of different posterior treatments and radiocarbon measurement. The results were also compared with SEM (Scanning Electron Microscoic) and Fourier Transform Infrared Spectroscopic observations. It was discovered that the sample prepared by the initial pre-treatment and cell sorter were not sufficiently pure and did not yield radiocarbon ages that were consistent with the terrestrial leaf fossils. Instead, the Acid-Base-Acid treatment with ultrafiltration following on from the cell sorter step proved to be highly effective in the removal of contaminants and improve the measured ages. The comparison with Suigetsu's terrestrial radiocarbon dataset also indicated that accuracy could be improved through closer assessment using the pollen taxa composition, carbon content (%C), and stable isotope ratios (δ¹³C) of the pollen concentrates. The age-depth models established by the radiocarbon dating of fossil pollen grains extracted from the Suigetsu sediments agree very well with that of plant macrofossils, and even improve the precision of the combined model. As long as handling was appropriate, the pollen concentrates prepared by the cell sorter provide reliable radiocarbon ages and the method can significantly contribute to Quaternary sciences in the future.     

Late Holocene vegetation and climate oscillations in the Qaidam Basin of the northeastern Tibetan Plateau

Pollen evidence from sediment cores at Hurleg and Toson lakes in the Qaidam Basin was obtained to examine vegetation and climatic change in the northeastern Qinghai-Tibetan Plateau. The chronologies were controlled by ²¹⁰Pb and ¹³⁷Cs analysis and AMS ¹⁴C dating. Pollen assemblages from both lakes are dominated by Chenopodiaceae (∼ 40%), Artemisia (∼ 30-35%) and Poaceae (∼ 20-25%), with continued occurrence but low abundance of Nitraria, Ephedra, and Cyperaceae. Artemisia/Chenopodiaceae (A/C) pollen ratios from two lakes show coherent large oscillations at centennial timescale during the last 1000 yr. A/C ratios were high around AD 1170, 1270, 1450, 1700 and 1920, suggesting that the vegetation was more “steppe-like” under a relatively moist climate than that during the intervening periods. Wet-dry climate shifts at the two lakes (2800 m asl) are in opposite phases to precipitation changes derived from tree-ring records in the surrounding mountains (> 3700 m asl) and to pollen and snow accumulation records from Dunde ice core (5300 m asl), showing that a dry climate in the basin corresponds with a wet interval in the mountains, especially around AD 1600. This contrasting pattern implies that topography might have played an important role in mediating moisture changes at regional scale in this topographically complex region.     

从浙江天台白垩纪蛋化石复原恐龙类群

浙江天台盆地白垩纪地层中,已发现了甲龙类及慢龙类等恐龙骨骼化石及数以千计的蛋化石,其中许多为恐龙蛋化石。根据国内外相同类型的蛋化石中迄今已发现的恐龙胚胎化石研究成果,可大致确定其中一部分蛋化石分别是由鸭嘴龙类、巨龙类、慢龙类、盗蛋龙类、伤齿龙类和暴龙类等恐龙所产。并发现鸭嘴龙类、巨龙类和慢龙类的圆形蛋、副圆形蛋在数量上占绝大多数,盗蛋龙的长形蛋和伤齿龙的棱柱形蛋较少,暴龙类的巨型长形蛋最少,从而反映了他们各自在生态金字塔中的位置。     

辽东半岛南部晚先寒武纪宏体生物序列

辽东半岛市部上先寒武系自下而上划分为4群15组,其中细河群的三个组即钓鱼台组、南芬组、桥头组产宏观藻类化石;五行山群的长岭子组、南关岭组产蠕虫和宏观藻类化石;金县群兴民村组产类水母化石,葛屯组产蠕虫、宏观藻类化石,上覆的下寒武统碱厂组产三叶虫和古杯动物化石。上先寒武系7个宏体生物化石层位构成一个连续的、完整的宏体生物序列,可分为4个演化阶段:①细河期宏观藻类发生发展阶段;②五行山期蠕虫发生发展阶段和宏观藻类发展阶段;③兴民村期类水母发生发展阶段;④葛屯期蠕虫和宏观藻类新的发展阶段。据此可以划分为4个生物群,即细河生物群(800Ma前)、五行山生物群(800—700Ma)、金县生物群(677Ma)、满家滩生物群(600Ma)。另外早寒武世三叶虫和古杯动物组成葫芦套生物群,为早寒武世晚期。辽东半岛与苏皖北部晚先寒武纪地层不仅沉积序列相同,而且宏体生物序列也基本相同,两区生物地层完全可以对比。辽东半岛南部晚先寒武纪宏体生物序列的建立及其在同一地层区的延展性,提高了本区晚先寒武纪地层剖面的地位。使其可能成为全球晚先寒武纪生物地层层型剖面。     

辽西中生代含鸟层及上下层位的划分和时代

辽宁西部中生代地层发育,在国内外同期地层研究中占有重要地位。辽西中生代鸟化石的发现,具有重要的科学价值。含鸟层位包括上侏罗统义县组含鸟层和下白垩统九佛堂组含鸟层。现共鉴定出鸟类化石１１个属１４个种,其中义县组鸟化石４个属６个种,地位最为重要。鉴于此,将义县组下部的沉积层划分出来,并建立了四合屯组,该组对寻找鸟类的祖先具有重要的意义。原土城子组一段具有组级岩石地层单位意义称为蒙古营子组。     

成矿古水热系统与热液铀矿床研究历史,现状与展望

介绍了成矿古水热系统与热液铀矿床研究的历史与现状。指出了以往研究只强调水及溶质起源，而对热源重视不够的欠缺。同时，结合热液铀 矿床的研究情况，对成矿古水热系统研究的下一步发展方向进行了展望。     

The first record of a bryophyte in Upper Cretaceous amber from Taimyr,northern Siberia: Taimyrobryum martynoviorum gen. et sp. nov. (Bryopsida)

Cretaceous bryophyte fossils are known only from a few localities and only a few are known in ultrastructural fidelity. We describe a fossil moss gametophyte from Upper Cretaceous Taimyr amber and place it in the fossil genus Taimyrobryum martynoviorum gen. et sp. nov. (Bryopsida). Its unbranched, somewhat zig-zagged stems with distantly spaced, spreading, narrowly lanceolate leaves and the unbranched costa match the gross morphology of Dicranidae; however, the uniformly prosenchymatous leaf cells contradict an affiliation to this subclass. The Yantardakh in the Taimyr Peninsula is the fourth and northernmost Cretaceous amber locality yielding inclusions of bryophytes.