Vivianne Berg-Madsen

The Upper Cambrian bradoriid ostracod Cyclotron lapworthi is a hesslandonid

Cyclotron lapworthi (Groom, 1902), one of the few British Cambrian bradoriid ostracod species known from a large number of specimens, is redescribed. It has an interdorsum, thus indicating a hesslandonid affinity. The ontogeny of C. lapworthi does not demonstrate a clear distinction of its individual moult stages but does show marked changes in the development of nodes and lobes. C. lapworthi shows wide variation in carapace shape possibly indicating that its valves were thin and relatively flexible. In England and Canada C. lapworthi is restricted to the Upper Cambrian Olenus Zone. C. lapworthi may also occur coevally in the Upper Cambrian of Sweden.

The Middle Cambrian Kalby and Borregård Members of Bornholm, Denmark

Abstract The Middle Cambrian Kalby Member of the Exsulans Limestone Formation exposed at the Laesa rivulet on the island of Bornholm, Denmark, consists of a lower marl bed (previously known as the Kalby clay) and an upper pyritic bed. The marl bed in its present development is an unconsolidated unit; it has abundant trilobite moulds, mainly phosphatic microfossils, and contains about 35 wt. % CaCO3 in the form of finely dispersed, non-cementing calcite grains. The marl bed is interpreted as a weathering residue of a former limestone corresponding to the Exsulans Limestone. In a consolidated state and soon after its deposition it was subjected to tectonic movements taking place in the Middle Cambrian. Its present lithology represents local decay of the carbonate rocks, including the overlying Andrarum Limestone Formation, in the Laesa area. The faunal analysis of both beds of the Kalby Member is much extended, the fauna showing great similarity to that of the Borregard Member of the Olea section, which sugge...

The Middle Cambrian of Bornholm, Denmark: A stratigraphical revision of the lower alum shale and associated anthraconites

Abstract The Middle Cambrian lower alum shale and the associated anthraconites are reexamined and revised bio- and lithostratigraphically. New finds of predominantly agnostid trilobites show that the sequence is far more restricted stratigraphically than hitherto supposed. Lithologically the anthraconite beds do not fulfil the definitions of the term anthraconite. Due to long tradition of use the name basal anthraconite is maintained for the lower limestone. The anthraconite overlying the alum shale is referred to as Hyolithes limestone, as it is a bio- and lithostratigraphical equivalent of the Hyolithes limestone in Sweden. The agnostid zonation of Westergard, used in and outside Scandinavia, is reviewed. The absence of the Ptychagnostus lundgreni — P. nathorsti Zone on Bornholm is proved. The validity of the zone of Ptychagnostus lundgreni — P. nathorsti is questioned, not only in Scandinavia but wherever the agnostid zonation of Westergard is used. A correlation with the interval-zones in North Americ...

A new mid-Cambrian trilobite fauna from Shropshire

An attempt to re-investigate the Acrothele prima Shale, formerly recorded as of Early Cambrian age, resulted in the discovery of a diverse Middle Cambrian trilobite fauna — a fortunate result considering the erroneous information surrounding the investigation of the Acrothele prima Shale. The new fauna, whose age approximates to the boundary between the gibbus Zone and fissus Zone, contains species not recorded previously in Shropshire: the trilobites are discussed and species described originally from New Brunswick are recorded from Britain for the first time, including Eccaparadoxides acadicus and Ctenocephalus (Hartella) matthewi .

The Bromell fossil collection at Uppsala University, Sweden : its history and the people behind it

Remains of 17th century cabinets of curiosity collections are held at the Museum of Evolution, Uppsala University, Sweden. Some of the oldest date back to the 1650s, and were included in the collection of Archiater, i.e. physician to the Crown, von Bromell (1679–1731). He is also known for publishing the first series of papers in Sweden to exclusively deal with palaeontology. Throughout his life he acquired specimens by collecting, buying or receiving in exchange to add to those he inherited from his father Olaus Bromelius, a famous botanist and physician. Information on the labels gives a glimpse of his network of friends, colleagues and fellow collectors, such as Kilian Stobaeus, Lars Roberg, Emanuel Swedenborg, Elias Brenner and Johan Döbelius. When Bromell died, his vast collections of books, coins, furniture, conchs, stuffed animals, minerals and fossils were sold off. The minerals and fossils were split up and owned by various persons during the following century. Parts owned by A. Lagerberg between the years 1746 and 1776 were bought in 1796 by Johan Afzelius and donated to Uppsala University at his death. Fossils and minerals earlier described by Bromell were in the care of The Royal Society of Science in Uppsala at least by 1791. Through the Institute of Geology, fossils accumulated over the centuries at Uppsala University eventually came together under the same roof in 1932, under professor Carl Wimans care at the then newly erected Palaeontology museum building. Today, about 300 fossils from the Bromell collection are preserved at the museum.

EOBUCANIA (Mollusca) from the Furongian (late Cambrian) of Sweden

Abstract The isometrically coiled mollusc Eobucania Kobayashi, 1955 is described from the Peltura scarabaeoides Zone (Furongian; late Cambrian) of Kinnekulle, southern Sweden, representing the oldest record of the genus and the first from the Cambrian of Sweden. While originally described from the Lower Ordovician strata within the McKay Group of British Columbia, Canada, additional species of Eobucania have been reported from the Lower Ordovician of Mexico, France and the Czech Republic, and ostensibly from the Lower Devonian of China. Eobucania has been widely interpreted as a bellerophontoidean gastropod, but placement within the monoplacophoran Class Tergomya is possible.

An orthothecid hyolith with a digestive tract from the early Cambrian of Bornholm, Denmark

Abstract The hyolith assemblage from the early Cambrian of Bornholm, Denmark, shows a higher diversity than contemporary assemblages in Baltoscandia. The most common species in the Green Shales (Læså Formation, Norretorp Member, Cambrian Stage 3), is Hyolithes [=Hyolithus] (Orthotheca) johnstrupi Holm, 1893. A specimen of this species shows a well-preserved and almost complete digestive tract, folded into an approximately 22 mm long chevron-like structure comprised of at least 20 arcuate loops on the ventral side and a flattened, gently sinuous to straight anal tube on the dorsal side. The thin, phosphatic outer shell layer of the conch is crushed under the digestive tract due to compaction while the digestive tract is preserved in three dimensions and appears undisturbed. The shape of the digestive tract is similar to that of the middle Cambrian Guduguwan hardmani (Etheridge) from Australia and the lower Cambrian specimens from Russia described by Meškova & Sysoev. The Danish specimen is probably an adult, lending support to the idea that the orthothecid digestive tract becomes more complex during ontogeny. Hyolithus (Orthotheca) johnstrupi is revised and here referred to Circotheca Sysoev, 1958.