Fig. 29 in Revision of the Andrena wollastoni group (Hymenoptera, Anthophila, Andrenidae) from the Madeira Archipelago and the Canary Islands: upgrading of three former subspecies and a description of three new subspecies

Fig. 29: Index spectrum (boxplots) of HL/HW index (head length to width) of the different taxa. Groups with the same letter are not significantly different. In the case of groups of two letters, significance exists only with one group identified by a single letter. Significance levels: * p <= 0,05; ** p <= 0,01; *** p <= 0,001; ns = not significant.