Trilobites are an extinct group of marine arthropods which existed during the Paleozoic era, from the Cambrian to
the Permian period about 540-245 million years ago. In Sweden there are trilobite fossils and other
Paleozoic fossils in sedimentary rocks from Cambrian, Ordovician and Silurian within the following districts:
Skåne, Öland, Gotland, Västergötland, Östergötland, Närke, Siljansringen and Jämtland.
The name tri-lob-ite refer to the trilobite body, which is formed into three lobes lengthwise; one
central lobe (axial lob) and two side lobes (pleural lobes)
The trilobites have a hard outer skeleton (exoskeleton), containing calcium carbonate and chitin.
In order to get bigger the trilobites periodically moulted, like all other arthropods. Entire trilobites are uncommon
because the skeleton breaks apart while moulting. The parts of the exoskeleton have the following terms:
| cephalon |
the complete head =cranidium with free cheeks |
 |
| thorax |
the middle body |
| pygidium |
the tail. |
| cranidium |
glabella with fixed cheeks |
| glabella |
the axial lobes extension in the cephalon |
| free cheek |
sometimes with spines |
| eye |
composite eye lenses |
| thorax segment |
the numbers of the thorax segments range from 2 for Agnostida to more than 40 for Ollenellidae |
| hypostoma |
shield under the mouth and stomach |
The trilobites have legs, located in pairs under each body segment.
The extremities
have also a fringed appendage probably with gill and swimming functions. Legs, antennae and other
soft parts are rarely preserved. This Triarthrus eatoni from the North American
strata of Beecherīs Trilobite Bed have however both extremities and antennae fossilized.
Many trilobites were capable of curling their body for protection.
You can find a much more complete description of trilobites at Dr Samuel M Gon IIIīs excellent site
A Guide to the Orders of Trilobites
On this page I have used Jan Bergströmīs classification, from his doctorīs
thesis Organization, life, and systematics of trilobites, published in
Fossil and Strata No. 2, pp 1-69, Pls. 1-5. Oslo, 27 th April, 1973
Bergström divides the trilobites into nine orders : Olenellida, Ptychopariida, Redlichiida,
Illaenida, Phacopida, Odontopleurida, Lichida, Corynexochida and Agnostida. This classification is
radically changed in comparison with the Treatise (Moore 1959), concerning the concepts of
Redlichiida, Phacopida, Odontopleurida and Ptychopariida.
The classification is rather complicated, especially when there are different concepts of the subdivision.
Example: Peltura scarabaeoides
| Phylum |
Arthropoda |
 |
| Class |
Trilobita |
| Order |
Redlichiida |
| Suborder |
Asaphina |
| Superfamily |
Olenacea |
| Family |
Olenidae |
| Subfamily |
Pelturinae |
| Genus |
Peltura |
| Species |
Peltura scarabaeoides |
My purpose with this page is to link photos to the majority of my best finds, hopefully to give
pleasure to other amateurs from far and near.
Below is a catalogue of the species I have
found in Sweden so far, divided into order and family/subfamily
Links to Swedish sites with trilobites
A Swedish collection of fossil photos, part 1,
part 2,
part 3,
part 4
Links to Norwegian sites with trilobites
Trilobites of Norway
Links to sites with Bohemian trilobites
Links to Japanese sites with trilobites
Fossiljapan
Agnostus
Links to sites with trilobites from Europe
Trilobites.es
Links to commercial sites with trilobites from Europe and Russia
Henskens Fossils
Famous Fossils
This page (URL: http://triloswede.com) is written by
Per Hansson , Lidköping, Sweden.
If you have comments, suggestions, questions, corrections or other messages, please e-mail me at
peltura@outlook.com
Latest update June 18 2025
First update in Januari 1997
