Fig 2.

Area of West Germany in the federal states of North Rhine-Westphalia, Rhineland-Palatinate and Hesse checked for Ae. j. japonicus in 2012 (a), 2013 (b), 2014 (c) and 2015 (d). Red squares: grid cells positive, green squares: grid cells negative by cemetery inspection, circles: grid cells with Ae. j. japonicus submissions to the ‘Mueckenatlas’; figures in the grid cells denote findings in May/August of the respective year with ‘1’, ‘2’, ‘3’ representing the number of cemeteries inspected until Ae. j. japonicus was found, ‘X’ representing three negative cemeteries in case only one of the two collection seasons was positive, and ‘-‘ meaning not sampled. The area framed in bold marks the reference area used for statistical analysis.