Four main immunity pathways in Drosophila melanogaster and their counterparts in three hymenopteran species. The four main immunity pathways are Toll, immunodeficiency (IMD), c-Jun N-terminal kinase (JNK), and Janus kinase/Signal transducers and activators of transcription (JAK/STAT). The hymenopterans are Apis mellifera, Nasonia vitripennis, and C. solmsi. Gray indicates genes occurring in all four species. Red indicates genes described from D. melanogaster but absent in all hymenopterans. Brown indicates genes absent in the chalcid N. vitripennis and C. solmsi, but present in D. melanogaster and A. mellifera. Blue shows genes absent in C. solmsi only. Green signposts outside infections such as Gram-positive and Gram-negative bacteria, and fungi. Yellow denotes antimicrobial peptides (details in Additional file 1: Table S11).