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''Paralejurus'' is a
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of
trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...
from the Late
Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleoz ...
to the Middle
Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, wh ...
of
Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
and
Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
.


Features

These animals, up to nine centimeters long, had an oval outline and a strongly arched exoskeleton. The cephalon has a smooth, detail-poor surface and an almost inconspicuous occipital bone behind the glabella in the transition to the thorax. The facet eyes have crescent-shaped lids. The thorax consists of ten narrow segments and a clearly arched and broad axial lobe ( rhachis ). The pygidium is very broad and denominate. The axillary lobe ends roundly and upwards. From this elevation, twelve to fourteen fine furrows extend radially. In contrast to the genus ''Scutellum'' with a pygidium with distinct furrows, in ''Paralejurus'' the pygidium was very smooth and strongly fused.


Sources

* ''Fossils'' (Smithsonian Handbooks) by David Ward (Page 65)
''Leonaspis''
in the
Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pal ...
Devonian trilobites of Africa Styginidae Corynexochida genera Silurian trilobites Devonian trilobites Trilobites of Africa Trilobites of Europe Silurian first appearances Middle Devonian genus extinctions {{Corynexochida-stub