Illaenus katzeri scale in cms CLASS - Trilobita ORDER - Ptychopariida FAMILY - Illaenidae GENUS/SPECIES - Illaenus katzeri ROCK UNIT - Barrandian beds AGE - Ordovician LOCALITY - Myto, Bohemia, Czechoslovakia Although this specimen was found in central Europe, Illaenus was "cosmopolitan", meaning that it is found all over the world in rocks of the same age. Trilobite migration from one area to another took place quickly. This makes sense when you consider that many sea floor creatures, like corals, can only move about during their larval (baby) stage, and even then they are pushed around by ocean currents. Trilobites and other crawling and swimming animals can move about during their entire life. PRI 2351C