Multiple sequence alignment was performed with individual CBD domains identified from peritrophins from P. papatasi and L. longipalpis. Pp1CBD1, Pp1CBD2, Pp1CBD3, and Pp1CBD4 are PpPer1 CBDs. Pp2CBD1 is the single CBD in PpPer2. Pp3CBD1 and Pp3CBD2 are the two CBDs identified in PpPer3. Lulo1CBD1, Lulo1CBD2, Lulo1CBD3, and Lulo1CBD4 are the four CBDs in LuloPer1. Lulo2CBD1 and Lulo3CBD1 are the single CBDs in LuloPer2 and in LuloPer3, respectively. Ll3CBD1 and Ll3CBD2 are CBDs in LlPer3. Pp3put and Ll3put are putative domains similar to CBDs identified in P. papatasi PpPer3 and in L. longipalpis Ll3Per3. Such putative domain sequences also were identified in the N-terminal region of C. felis PL1 - CfPl1put; C. quinquefasciatus conserved hypothetical protein - Cq16put; and A. aegypti Ae51put, Ae45put, and Ae52put. The six conserved cysteines are highlighted in grey with the conserved aromatic amino acids predicted to bind chitin shown in white with black highlight; HRM motifs are underlined. Conserved amino acid residues displayed exclusively by the putative CBD domain sequences are shown in red, and the additional cysteine residues are indicated by asterisk (*).