Abbreviations
Mar.: Maritime district
Boul.: Boulogne district
Pic.: Picardy district
Fl.: Flemish district
Camp.: Campine district
Brab.: Brabant district
Mosan: Meuse district
Ard.: Ardenne district
Lorr.: Lorraine district
RRR: extremely rare, known from 1 locality
RR: very rare, known from 2-4 localities (Mar., Boul.: 2-3 localities)
R: rare, known from 5-9 localities (Mar., Boul.: 4-6 localities)
AR: rather rare, known from < 25 % of the 4×4 km2 IFBL squares (≥ 10 loc.; Mar., Boul.: ≥ 7 loc.)
AC: rather common, known from 25-50 % of the IFBL squares
C: common, known from 50-75 % of the IFBL squares
CC: very common, known from 75-100 % of the IFBL squares