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''Erbenochile'' is a genus of spinose phacopid (acastid) trilobite found in Lower to Middle Devonian age rocks from Algeria and Morocco.〔 〕〔 〕 Originally described from an isolated pygidium (the posterior body part or shield),〔 the first complete articulated specimen of ''E. erbeni'' revealed the presence of extraordinarily tall eyes: Number of lenses has been estimated at 560〔 or 450 incomplete preservation accounting for the uncertainty. A lens count of 18 lenses per file is unusually high (twice that of closely related genus) and accounts for the height of the eye, as opposed to a noticeable increase in the size of the individual lenses.〔 A recently found species (''E. issoumourensis'') has smaller eyes, with fewer files (33-35) and fewer lenses per file (13-14 max) than ''E. erbeni''.〔 ''E. erbeni'' eyes allow full 360 degree coverage in the horizontal plane and were high enough to allow the trilobite to see backwards over its thorax. The presence of eye shades, blocking glare from over head, validates the suggestion that (at least some) trilobites were diurnal and not nocturnal, == Distribution == * ''E. erbeni'' has been found in the latest Lower Devonian of Algeria (upper Emsian strata at Ougarta) and Morocco (Timrhanrhart Formation at section Foum Zguid III). * ''E. issoumourensis'' is known from the latest Lower Devonian or possibly earliest middle Devonian of Morocco (upper Emsian or lower Eifelian, ''Erbenochile'' bed, El Otfal Formation, Jbel Issoumour, near Alnif southeastern Morocco 30°58'14.5 N - 05°01'44.3W).〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Erbenochile」の詳細全文を読む スポンサード リンク
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