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A new family of Scarabaeoidea is revealed from the Cretaceous amber of Myanmar (earliest Cenomanian, near 100 Ma), on a series of males and females, most in perfect condition. Passalopalpidae fam. nov., Passalopalpus cheni gen. et sp. nov., are probably extinct since a long time. Observations were made on the whole body (head, thorax, abdomen) and appendages (mouthparts, antennae, legs, wings). Most characters are remarkable and plesiomorphic, compared to Passalidae Leach, as well as to some other Scarabaeoidea. Morphological characteristics demonstrate that the fossil species is typically « passaloid », but that it cannot belongs to Passalidae. Passalopalpidae and Passalidae are clearly distinct families, with strong assumption to be sister groups. The systematic interpretation of the fossil could fill a historic gap: the sister group of Passalidae had been established previously never in a solid way. Passalids are Gondwanian, whereas passalopalpids lived on former eastern Laurasia. Vicariance of both taxa, each on one of the super-continents, seems to support recent hypotheses of phylogeny and paleobiogeography for Passalidae. Other preliminary notes are given on the morphology, biology and phylogenetic relationships of passalopalpids.  相似文献   
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A peat bed found under solifluction deposits on Godøya island, western Norway, accumulated during a few decades around 11 000 yr BP, at the end of the Allerød period of the Late Weichselian. Palaeoecological investigations showed a local vegetation succession on wet sand culminating in a mire community dominated by Carex nigra. Periodic flooding brought in sand and silt, which decreased as drainage was impeded sufficiently for standing water to develop. The surrounding terrestrial vegetation was dominated by Salix scrub, with some open heath and alpine habitats nearby. Apart from two aquatic species, the 29 insect taxa recorded are characteristic of alpine heaths, plant litter (under Salix scrub) and stream-sides. Their remains, together with the terrestrial plant macrofossils, were washed into the mire from nearby. Because the fossils are locally derived, the environmental reconstructions are of the actual conditions at Godøy at ca. 11 000 yr BP. Palaeotemperature estimates from beetles and plants are in agreement. The coleopteran estimates (Mutual Climatic Range Method) suggest mean July temperatures of 10–13°C, slightly cooler than today (13.5°), and January temperatures between +1 and ?10°C, similar to or much colder than today. Summer temperature estimates from individual plant taxa indicate that temperatures during the Allerød period were similar to today's, but estimates from the reconstructed vegetation and timber-line positions give estimates up to 3.5° cooler. Temperatures fell 2.5–7.5°C at the Younger Dryas. This abrupt and severe cooling initiated the solifluction processes on Godøya that buried the peat. The Godøy peat bed and its contained fossils provide a rare glimpse of Allerød biota and environments at the local (site) scale.  相似文献   
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Nine cores were taken from a damp depression at Dingé, Ille-et-Vilaine, northwest France. Analyses of the pollen, plant macrofossil and Coleoptera remains preserved in the same organic samples of two profiles suggest a temperate vegetation characterised by a mixed deciduous forest with mesophilous taxa (Carpinus, Fagus, Quercus) followed by a coniferous forest with Pinus and Picea. The determination of plant taxa to species was made either directly through the identification of plant macrofossil remains and pollen or indirectly through the identification of phytophagous Coleoptera specifically related to certain plants. Stratigraphical information derived from pollen, plant macrofossil and insect data indicates that this sequence may be correlated with a temperate episode older than the Eemian and younger than the Holsteinian, possibly the Bouchet 2 (Oxygen Isotope Stage 7c) or Bouchet 3 (Oxygen Isotope Stage 7a) temperate periods or the Landos Interglacial (Oxygen Isotope Stage 9 pro parte). © 1997 John Wiley & Sons, Ltd.  相似文献   
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A new species belonging to the extant dermestid genus Attagenus, Attagenus burmiticus sp. nov., is described and illustrated based on a well-preserved specimen from the Upper Cretaceous Burmese amber. The discovery suggests that Attagenus is an ancient group, originating as early as in the mid-Cretaceous. Along with another species of Attagenus known from the Upper Cretaceous New Jersey amber, it implies that Attagenus were widespread in the Mesoozic.  相似文献   
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A second species of the extinct scydmaenine genus Cretoleptochromus Cai & Huang, C. burmiticus sp. nov., is described and figured based on three exquisitely preserved specimens embedded in mid-Cretaceous Burmese amber. The new taxon possesses an extremely elongate body form and strongly extended legs and antennae that provide reliable means for species diagnosis and a ready separation from the only known congener, the type species C. archaicus Cai & Huang, also reported from Burmese amber. The morphology of C. burmiticus also suggests that this species was probably an active diurnal predator living in open environments.  相似文献   
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Thirty-six Coleoptera (beetle) taxa and other insects were identified from the late-glacial and early-Holocene sediments at Kråkenes Lake. Compared with other Scandinavian late-glacial sites, this is a rather sparse record. The water beetles found in the Allerod are characteristic of a poorly vegetated clear-water lake. The terrestrial fauna is indicative of dwarf-shrub and moss vegetation. A marked decline in the number of species at the start of the Younger Dryas was rather rapid, probably over less than 80 calendar yrs. No obligate tundra species replaced the Allerod fauna. Most of the Younger Dryas is virtually devoid of beetles. The increase in numbers and diversity of both aquatic and terrestrial species at the Younger Dryas/Holocene transition is very rapid. After an initial pioneer stage, beetles associated with dwarf-shrub heath and willow scrub appeared, but no obligate tree or forest taxa were recorded.Mutual Climatic Range (MCR) temperature reconstructions suggest that the Allerod was colder and more continental than present. The near absence of beetles in the Younger Dryas probably reflects very cold conditions. A rapid temperature rise at the start of the Holocene resulted in a warmer and more continental climate than present.  相似文献   
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Fossil smicripid beetles are very rare. Here we describe and figure the first Mesozoic representative of Smicripidae. Smicrips cretacea sp. nov., a new species belonging to the extant Smicrips LeConte is preserved in the Upper Cretaceous amber from northern Myanmar. Our discovery suggests that Smicrips is an ancient group, originating at least in the earliest Late Cretaceous. Together with other two fossil Smicrips species from the Eocene of Europe, it reinforces the hypothesis that the Recent distribution of Smicripidae is relict, and the family was more widespread in the Mesozoic and early Cenozoic than it is in the Recent.  相似文献   
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