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''Chotecops'' is a genus of trilobites from the order Phacopida, suborder Phacopina, family Phacopidae. It was initially erected as a subgenus of ''Phacops'' but some later authors thought it distinctive enough to raise its status. Species assigned to this genus occur between the Emsian and the Famennian. ''Chotecops'' is the most abundant trilobite in the Hunsrück Slate and due to the excellent preservation, often soft tissue such as antennae and legs have been preserved as a thin sheet of pyrite. == Description == Like in all sighted Phacopina, the eyes of ''Chotecops'' are compounded of very large, separately set lenses without a common cornea (so called schizochroal eyes), and like almost all other Phacopina, the articulate mid-length part of the body (or thorax) in ''Chotecops'' has 11 segments. The central raised area of the cephalon (called glabella) consists from back to front of an occipital ring, but unlike in its close relative ''Phacops'' the preoccipital ring in ''Chotecops'' is flat and not reduced to its sides, and the furrow defining its front (S1) is shallow. One or two pairs of furrows (S2 and S3) may be visible further to the front which are weak at best. The large frontal lobe is moderately vaulted and falls steeply to the furrow that defines the border at its front. The space between the glabella and the eyebrow (or palpebral area) is flat. The headshield has a finer sculpture. The tailshield (or pygidium) is weakly furrowed. These characters distinguish it from ''Phacops''. Some known species and locations.〔(Trilobites of the Hunsrück Slate, Germany )〕 * ''C. ferdinandi'' (Kayser, 1880), Hunsrück Germany. * ''C. opitzi'' Struve, 1985, Hunsrück Germany. * ''C. zofiae'' Chlupac, 1993, is known from the Middle or Upper Devonian of Poland (near the Givetian/Frasnian border, Holy Cross Mountains). 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「Chotecops」の詳細全文を読む スポンサード リンク
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