Query: keyword: "Upper Cretaceous"
|Authors||J.W.M. Jagt, M.A. Salamon|
|Title||Late Cretaceous bourgueticrinid crinoids from southern Poland – preliminary observations|
|Keywords||Crinoidea; Bourgueticrinidae; Upper Cretaceous; southern Poland|
|Abstract||Dissociated skeletal elements of bourgueticrinid crinoids, comprising mostly columnals, radicular cirri, a few cups and some brachials, are recorded from Turonian-Maastrichtian strata of southern Poland (Miechów Trough, Kraków-Cze˛stochowa Upland, Holy Cross Mountains and Opole Trough). Published records of bourgueticrinids from Poland are surprisingly few; only specifically indeterminate columnals, radicular cirri and a sole proximale, plus a single cup of Bourgueticrinus utriculatus have been noted. The present material, although limited, clearly demonstrates that these crinoids must have been less rare than anticipated and are, in fact, distributed throughout the entire Upper Cretaceous sequence in this area. The majority of bourgueticrinids had an extensive root system (radicular cirri) and their presence thus allows some conclusions regarding substrate consistency (softground) to be drawn. A striking feature of the present faunules is the small cup size in comparison to material from elsewhere in northern Europe, possibly an ecophenotypical expression. Species distinction within the genus Bourgueticrinus is still contentious and we refer to our material in open nomenclature.|
|Classification||38.22 ; 42.72|
|Download paper|| http://www.repository.naturalis.nl/document/45037 |