Aculifera
Introduction '''Aculifera''' (older name: '''Amphineura''') is a proposed clade of molluscs incorporating those groups that have no conch or shell, that is, the Polyplacophora, Caudofoveata (=Chaetodermomorpha) and Solenogastres (=Neomeniomorpha).It is sister to the Conchifera.The oldest known aculiferan is ''Qaleruaqia'', which was found in the Aftenstjernesø Formation in Greenland, which dates back to the Cambrian Stage 4.
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