The Basonym reference article from the English Wikipedia on 24-Apr-2004
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Basonym

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A basonym is an obsolete name for a biological species or genus which has been replaced by a new name. For instance the bacterium Moraxella catarrhalis (current name) which causes respiratory tract infections in humans was formerly known as Branhamella catarrhalis (basonym). Basonyms are examples of Synonymy in scientific classification.