Fig. 2

A Amino acid alignment for insect pre-ecdysis triggering hormone (PETH), ecdysis triggering hormones (ETH) 1 and 2, and carcikinin, and carcikinin-like peptides from crustaceans, myriapods and chelicerates. Identical residues are highlighted black and conserved substitutions are highlighted grey. B Phylogenetic tree of insect ETHs, carcikinin, and carcikinin-like peptides constructed using the Neighbor-joining method. Nodes supported by bootstrap values of < 50% have been collapsed. Protein sequences for Scylla paramamosain, Eriocheir sinensis, Homarus americanus, Procambarus clarkii, Litopenaeus vannamei, and Macrobranchium rosenbergii taken from [27]. Accession codes for sequences taken from the NCBI database: Cancer borealis, GEFB01012879.1; Meganyctiphanes norvegica, GETT01085899.1; Scolopendra subspinipes dehaani, GBIM01000685.1; Pardosa pseudoannulata, GCKE01050112.1; Parasteatoda tepidariorum, XM_016075645.1; Nothrus palustris, GEYJ01054236.1; Tetranychus urticae, XM_015935221.1; Daphnia pulex, EFX73380.1; Choristoneura fumiferana, JX878448.1; Manduca sexta, AF165427.1; Bombyx mori, NM_001172272.1; Tribolium castaneum, XM_008196841.2; Drosophila melanogaster, NM_079960.4; Sarcophaga crassipalpis, LC018445.1; Apis mellifera, NM_001142607.1; Nasonia vitripennis, NM_001142635.1; Drosophila melanogaster Trissin, NP_650471.1