EDIT

  $ext_links_default["epic"] = array(

    'id' => "epic",

    'link' => 'http://epic.kew.org/searchepic/summaryquery.do?scientificName=[cdm:taxon_name]&searchAll=true&categories=names&categories=bibl&categories=colln&categories=taxon&categories=flora',

    'title' => 'ePIC',

    'weight' => 0,

    'status' => 1,

    'category' => 'General',

  );

  //  $ext_links_default["arkive"] = array(

  //    // domain no longer exists! Remove extlink?

  //    'id' => "arkive",

  //    'link' => 'http://www.arkive.org/search.html?q=[cdm:taxon_name]&output=xml_no_dtd&client=arkive-images&site=arkive-images&ie=utf8&oe=utf8&num=20&proxystylesheet=tng-search&filter=0&getfields=*',

  //    'title' => 'ARKive',

  //    'weight' => 0,

  //    'status' => 0,

  //    'category' => 'Images',

  //  );