Trimeroceratidae

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m (Protected "Trimeroceratidae" ([move=sysop] (indefinite)))
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  [[Trimeroceratidae|<==]]Trimeroceratidae
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The Middle Silurian Trimeroceratidae resembled the related Hemiphragmoceratidae in having the shell aperture visored by encroaching lappets. The two families mainly differed in the structure of the siphuncle, that of Trimeroceratidae being slender and without actinosiphonate deposits.
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'''Characters''' (from Sweet 1964): Exogastric, mostly compressed brevicones with slender, empty siphuncles. Aperture visored; mature peristome with median dorsal sinus.
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==Taxonomy==
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  [[Oncoceratidae|<==]]Trimeroceratidae
     |--''Clathroceras'' Foerste 1926 S64
     |--''Clathroceras'' Foerste 1926 S64
     |    `--*''C. sulcatum'' (Barrande 1865) [=''Phragmoceras sulcatum''] S64
     |    `--*''C. sulcatum'' (Barrande 1865) [=''Phragmoceras sulcatum''] S64

Revision as of 02:33, 19 January 2011

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