Dalmanites
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Dalmanites | ||||||||||||||||
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Dalmanites limulurus, a trilobite of the genus Dalmanites
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Dalmanites is a genus of trilobite in the order Phacopida.
The trilobites of this genus have slightly convex exoskeletons with an average diameter of 4-7 cm (1.5 - 2.75 in). The cephalon is semicircular or parabolic. The glabella (center portion of the head) is often pear-shaped, and tapers outward toward the front. The glabella also always contains three pairs of obvious glabellar furrows. Also prominent are the large mosaic (schizochroal) eyes.
The thorax is composed of six to eleven pleural ribs, with the relatively large pygidium being composed of several additional fused segments. The pygidium ends in a striking tail spike.
During the Ordovician and Silurian periods, the genus Dalmanites was widespread all over the world, inhabiting a variety of climates and sea conditions.
[edit] References
- Ivanov, M.; Hrdlickova, S. and Gregorova, R. The Complete Encyclopedia of Fossils. Rebo International b.v., Lisse, The Netherlands (2001, reprinted 2004).