Palaeoenvironment and taphonomy of a Late Jurassic (Late Tithonian) Lagerstätte from central Poland

A rich assemblage of exceptionally preserved marine and terrestrial fossils occurs in fine‐grained limestones in the upper part of the Late Tithonian (Middle Volgian) shallowing upward carbonate sequence in Central Poland. The richest horizon, a deposit known locally as the Corbulomima horizon, is named after the shallow burrowing suspension feeding bivalve Corbulomima obscura, moulds of which occur in densities of up to 500 per square metre on some bedding planes. The fauna in this bed also includes organic and phosphatic remains of a wide range of other creatures including the exuviae of limulids and decapods, disarticulated fish skeletons and rare isolated pterosaur bones and teeth. There are also perfectly preserved dragonfly wings and beetle exoskeletons. The average stable carbon and oxygen isotope values for ostracod shells and fine‐grained sediment from this horizon suggest precipitation of the calcium carbonate from warm seawater of normal marine salinity. The carbonate sediments overlying the fossiliferous horizon have been interpreted as nearshore to shoreface facies. These pass abruptly into coarse reworked intraclastic sediments interpreted as possible tsunami or storm surge over‐wash deposits. The clasts in this deposit have more positive oxygen isotope values than those in the underlying limestone, which may indicate that they were lithified in a slightly more evaporative, perhaps intertidal, setting. The succession terminates with silicified fine‐grained limestones likely to have formed in extremely shallow lagoonal environments. In contrast with the Solnhofen limestones of Lower Tithonian age in south‐central Germany the Corbulomima horizon is interpreted as a transitional deposit formed in a shallow marine setting by rapid burial with elements of both Konservat‐ and Konzentrat‐Lagerstätte preservation. □Konzentrat and Konservat‐Lagerstätte, Taphonomy, Palaeoenvironment, Paleogeography, Late Jurassic, Poland.     

FENESTRATE BRYOZOAN GENERA BASED ON SPECIES FROM IRELAND ORIGINALLY DESCRIBED BY FREDERICK M'COY IN 1844

Abstract:  A large number of fenestrate bryozoan species were named in 'A Synopsis of the Characters of the Carboniferous Limestone Fossils of Ireland' by Frederick M'Coy (1844). At the same time, M'Coy named the bryozoan genera Ichthyorachis , Ptylopora and Polypora , each of which by monotypy or by subsequent designation was based on new species within that work. Subsequently, d' Orbigny (1849) named Fenestrellina with the type species Fenestella crassa M'Coy, 1844 as type species; Miller (1961) named Parafenestella with the type species Fenestella formosa M'Coy, 1844 as type species; and Wyse Jackson (1988) named Baculopora with the type species Vincularia megastoma M'Coy, 1844. We re-describe here in more detail than previously the fenestrate type species originally published in M'Coy (1844), provide diagnoses of the genera, and compare the nineteenth century genera with more recently named genera that have been discriminated specifically from them.     

Temporal and geographic variation in parasitoid attack with no evidence for ant protection of the Melissa blue butterfly,Lycaeides melissa

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The Linnaean Species of the Families Fanniidae, Anthomyiidae and Muscidae (Insecta: Diptera)

Linnaeus described eleven species in the genera Musca and Conops that are now placed in the Fanniidae, Anthomyiidae and Muscidae. A study is presented of the types and other material of these three families in his collection.