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Deiphon
''Deiphon'' is a distinctive genus of Silurian phacopid trilobites of the family Cheiruridae found in Western and Central Europe, and in Central and Eastern United States. The type species, ''D. forbesi'', from Bohemia, in what is now the Czech Republic, was discovered and described by the French paleontologist, Joachim Barrande in 1850.
==Description==
The glabella was inflated, and globular-shaped, and covered in small wart-like bumps. If it was filled with fat, or oil, the glabellum would have helped to have made the creature positively buoyant. On the other hand, trilobites with large glabellae are often suspected of being predatory, as the volume of glabella would be filled with digestive organs, or used to store captured/swallowed prey. The free cheeks of the cephalon formed a pair of long, curved spines, and the segments of the pleural lobes were separated and elongated to form rib-like struts. These modifications, along with the "V" shaped pygidium give these trilobites a cartoon "fish-skeleton" appearance. The defensive value of these highly elongate spines is also apparent, as they would have stuck in the throats of vertebrate predators, such as the Silurian acanthodian ''Nostolepis''.
Each species differed from each other in the sizes of their glabella, as well as the size and curves of the pygidium and free cheek spines.
Cheirurids had the ability to enroll to protect their softer ventral area, and the spines would have thrust upward and outward. In all adult specimens of the genus, the body has up to nine segments, not including the cephalon or pygidium (which is formed from at least two fused and reduced segments).
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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