the appearance on their territory or part of their territory of any species included on the Union list whose presence was previously unknown in their territory or in part of their territory;
láithreacht, ar a gcríoch nó ar chuid dá gcríoch, aon speicis atá ar liosta an Aontais, nárbh eol é a bheith ann roimhe sin ina gcríoch nó i gcuid dá gcríoch;