• When plotting the different 'Orsten' fossils on a World map, it becomes evident that these reflect the continent situation in the Cambrian quite well: After the break-up of the large super continent Rodinia at the end of the Precambrian, a number of smaller continents lay like pearls on a line near the equator, north of the remaining Gondwana continent.
  • Yet, no 'Orsten'-type fossils have been reported from the continental coast of Gondwana so far, though the so-called "small shellies" are numerous (more on these in due course; see, e.g. papers by O. Elicki). The zero record of ‚Orsten’-type fossils from any of the coasts around the Gondwana continent requires further consideration.

  • The 8 areas from which Orsten fossils have become known so far are from 4 continents:

    • North America

      • Nevada, USA: only Markuelia specimens

      • Eastern Canada:, type-A larvae and pentastomids

    • Europe

      • Comley, England: only a few phosphatocopine youngsters so far

      • Southern Sweden: the bulk of material, incl. Agnostus pisiformis with limbs and a lobopode, no nemathelminths so far

      • Northwestern Poland: Skara specimens, phosphatocopines and a stem crustacean named Cambrocaris baltica

    • Asia

      • Olenek uplift, Siberia: many empty shells of phosphatocopines and 4 specimens of a stem tardigrade
        Guizhu, China: Lower to Upper Cambrian taxa, incl. eucrustaceans, such as a Skara, Yicaris dianensis, Wujicaris muelleri and phosphatocopines

    • Australia

      • Locations south of Mount Isa, margin of Georgina Basin, Northern Territory: Nemathelminths, phosphatocopines and type-A larvae

  • In detail, there seems to be one faunistic connection Laurentia-Baltica-China (preferentially series 3 and Furongian, about the former Middle to late Cambrian; see website ICS). Another connection seems to exist between Sibiria, China, Australia and North America - Nevada (pref. series 2 and 3). This is especially apparent when including the occurrences of the cycloneuralian nemathelminth embryo Markuelia – see below.

  • Of the Crustacea, the Phosphatocopina occur in most localities, are the by far most abundant faunal elements, and have a long geological record. The oldest in 3D of a phosphatocopine with appendages is Klausmuelleria from Comley, England, so far (possibly terreneuvian [series 1], former lower Cambrian), those from Siberia (possibly series 2) are all queezed shields only. Phosphatocopines from series 2 (possibly series 2) of Australia have no apparent 
    systematic connection to those of the series 3 and Furongian faunas (those known with appendages are lacking exopods).

  • Remarkably widespread are the type-A larvae, most likely nauplii of still unknown eucrstaceans – therefore the oldest record of true (eucrustacean) nauplii so far. They occur in Canada, Sweden and Australia and range from possibly series 2 to the lower Ordovician (former Middle Cambrian to Lower Ordovician).

  • Skaracarida, representatives of Eucrustacea, have also been reported from more localities than just Sweden: one record is from Poland (series 3), another is from China (series 3 or Furongian, Dong et al. 2005), the oldest specimen is from series 2 (former Middle 
    Cambrian) of Australia.

  • Now we have evidence also of eucrustaceans from series 2, Lower Cambrian, of China. Yicaris dianensis, in 2007 described in a Nature paper (see references) is know form several larval stages, the smallest having already a few trunk segments. The exciting structure of the new form is its epipodites, three in number, that developed from small setae at the outer base of the limbs from the maxilla backwards (maxillula has only two setae there).

    The latest shoot was on the oldest metanauplius found so far, which is strikingly similar to those of modern entomostracan crustaceans, particularly those of barnacles. The paper on this new form, named Wujicaris muelleri, appeared 2010 in Current Biology!

  • Lobopodian stem arthropods (Artrhopoda s. l.) in 3D preservation are known only from Sweden (published 2008 as Orstotubulus evamuellerae). Yet they have been reported before in flat preservation from China, the U.S.A. and northern Greenland (Hadranax augustus Budd & Peel,1998). This might however change in due course due to new findings by one of our colleagues. 
    Considering also the Microdictyon „buttons„ in small-shelly assemblages, shelly plates of certain lobopodians, the range of lobopodians is apparently much wider.

  • Tardigrada, another stem-arthropod taxon, are known from possibly series 2, formerly Middle Cambrian, of Siberia only (still to be described taxonomically).

  • Pentastomida have been discovered, so far, in Newfoundland and in Sweden (late Cambrian to Lower 
    Ordovician). Remarkably, these do not occur together with any of the other arthropods, but only with conodonts, and they seem to be restricted to reworked horizons. This mighgt give some information on their occurrence and life strategies.

    Pentastomids represent, apart from one record of a Markuelia specimen from the USA, the youngest forms in the
     classical 'Orsten' preservation. Notably, pentastomids co-occur exclusively with conodonts, for us this is an interesting hint to their possible (most likely?) host/parasite association.

  • Besides arthropods, there is only one more taxon preserved in Orsten type 3D preservation, namely the cycloneuralian nemathelminths. This in-group taxon of the roundworms possesses a chitin-bearing cuticle that has to be moulted, similar to the situation in arthropods.

    Longer known are the so-called palaeoscolecids, long worms with a cuticle made of
     numerous small, button-like plates (Müller & Hinz 1993). Such plates have even been described before the finds of isolatedpieces of cuticle – plates called Hadimopanella etc. – within the "small shelly" assemblages.

  • The embryonic nemathelminth Markuelia (actually a late larva still inside the egg) has been found in Siberia, China, Australia and the U.S.A., its geological record ranges from the Cambrian series 2 to the Lower Ordovician. Our paper on a new species from Australia 

    has just appeared (see our page on finished projects).

  • More nemathelminths are known from the Cambrian series 2 from Australia. The first paper on a larva-like form is out since 2008 (see list of references!), the paper on a number of loricate larvae appeared in 2009 (see our page on finished projects).

It also becomes clear that preservation of 'Orsten'-type fossils from different times may be caused by different reasons and are not necessarily from nodular limestones, as in Västergötland, Sweden. This will be investigated in more detail in the future.

Our still up-to-date joint paper about general aspects of the 'Orsten':

Maas, A. Braun, A., Dong Xiping, Donoghue, P., Müller, K.J., Olempska, E., Repetski, J.E., Siveter, D.J., Stein, M. & Waloszek, D. 2006. The ‘Orsten’ – more than a Cambrian Konservat-Lagerstätte yielding exceptional preservation. Palaeoworld 15, 266-282.