Trilobites ENG
Trilobites are a popular and very diverse extinct group of arthropods present exclusively in Paleozoic period – the first ones appeared in Cambrian and the last ones became extinct at the end of Permian. Their characteristic feature is a flattened body, commonly covered with a hard mineralized shell and segmented into three units (lobes) consisting of a various number of segments: cephalon (head-shield), thorax, and pygidium (tail-shield). Each of them bears one pair of limbs that are adapted, apart from walking or swimming, to serve other functions as well (antennae, mandibles, gills, etc.). Trilobites were exclusively marine organisms actively swimming in water or floating in currents, crawling or bouncing on the sea bottom or burrowed into it. They scavenged particles of organic matter or filtered them from water; some of them were even predatory or parasitic. Various species differed in size, from several millimetres up to 75 centimetres.
The presence of trilobites in the Bohemian Paradise Geopark was successfully proven very recently. Surprisingly, they were discovered in metamorphic rocks from the Krkonoše-Jizera Crystalline Complex. The abandoned, partly flooded quarries near Železný Brod, previously serving for extraction of phyllites (thatching slate), yielded not only a great number of trace fossils, but also unique fossils of trilobites (genus Apatokephalus, Pliomerops etc.) and bivalves that prove the age of these rocks as Ordovician.