01820nas a2200145 4500008004100000022001400041245009400055210006900149260001600218520131700234100001601551700001601567700002101583856007001604 2021 eng d a0031-022000aA new look at Eccaparadoxides (Cambrian, Trilobita) and its biostratigraphic significance0 anew look at Eccaparadoxides Cambrian Trilobita and its biostrati cOct-12-20213 a

Eccaparadoxides is a geographically widely distributed trilobite genus that occurs in the middle part of the Cambrian System. However, the systematically important morphologic characteristics that can be used to differentiate taxa are often problematical in their application. A review of the large number (over 30) of significant species or forms assigned to Eccaparadoxides clearly indicates that only the pygidia offer fairly reliable morphologic criteria that can be used taxonomically and phylogenetically. The pygidia allow for recognition of four different morphological groups (pusillus, lamellatus, pradoanus and asturianus) of which the asturianus group can only be questionably assigned to the genus. Species known only from cranidia cannot be assigned to Eccaparadoxides with certainty. This study refines the biostratigraphy for the interval from the upper Wuliuan to the middle Drumian and shows that this interval brackets the range of most Eccaparadoxides species. The genera or subgenera Baltoparadoxides, Rejkocephalus and Macrocerca are evaluated. Eccaparadoxides zelus, E. epimetheus and Eccaparadoxides? hestia are newly proposed species.

1 aGeyer, Gerd1 aLanding, E.1 aŻylińska, Anna uhttps://link.springer.com/article/10.1007/s12542-021-00580-9#Abs1