Illaenus crassicauda
| Illaenus crassicauda Temporal range: Middle Ordovician | |
|---|---|
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| Fossil of Illaenus crassicauda from Sweden, on display at Galerie de paléontologie et d'anatomie comparée in Paris | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Trilobita |
| Order: | Corynexochida |
| Family: | Illaenidae |
| Genus: | Illaenus |
| Species: | †I. crassicauda |
| Binomial name | |
| †Illaenus crassicauda Wahlenberg 1826 | |
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Illaenus crassicauda is a species of trilobites belonging to the family Illaenidae. These trilobites lived in the middle Ordovician and in the Silurian age (443 - 418 million years ago). Fossils of this species have been found in the sediments of Sweden and Russia. [1][2]
Etymology
The Latin species name crassicauda means "fat-tailed", with reference to the shape of the pygidium.
Description
Illaenus crassicauda can reach a length of about 14 centimetres (5.5 in). These trilobites are without glabella and without articulation of the tail. The cephalon has a high profile. The large bulbous head are distant from the axis of the head, close to the margin. [3]
References
- V. Jaanusson Zur Fauna und zur Korrelation der Kalksteine mit Illaenus crassicauda (sog. Flagkalk) im Siljan-Gebiet Dalarnas Geologiska Föreningen i Stockholm Förhandlingar - Volume 69, Issue 1, 1947