Asaphidae is a family of asaphidtrilobites. Although the first genera originate in Upper Cambrian marine strata, the family becomes the most widely distributed and most species-rich trilobite family during the Ordovician. 754 species assigned to 146 genera are included in Asaphidae.
Distribution
Most Asaphinae are characteristic of Baltica. Isotelinae genera are concentrated in Laurentia. The genera of Nobiliasaphinae are distributed in tropical Gondwana and South China. The genera of Ogygiocaridinae occur in Avalonia, Gondwana and Baltica. Asaphidae asaphids were already fairly common during the Upper-Cambrian, when 14 genera are known from Australia, North- and South-China. The last members of the family died-out at the end of the Ordovician.[2]
^J.M. Adrian (2014). "20. A synopsis of Ordovician trilobite distribution and diversity". In D.A.T. Harper; T. Servais (eds.). Early Palaeozoic Biogeography and Palaeogeography. Memoirs of the Geological Society of London. Vol. 38. Geological Society of London. p. 490. ISBN978-1862393738.
^S. M. Gon III. "Order Asaphida". Archived from the original on 6 January 2011. Retrieved December 7, 2010.