Split network graph constructed from a global alignment of 63 ompA sequences retrieved from GenBank. Accession numbers are shown for each sequence represented. The length of connecting lines between two items is equivalent to their genetic distance. The scale bar denotes 1 substitution per 100 nucleotides. Clades representing an established genotype of C. psittaci are encircled by a dashed line and designated accordingly in bold print. Provisional genotypes are designated as suggested in Table 1. Clades representing other Chlamydophila spp. are encircled by a solid line and labeled with the species name. Basic data of the strains represented by accession numbers can be found in Additional file 3. Fig. 1a Detail showing the ABE cluster. Subgroups of genotypes A and E/B are indicated at the respective GenBank accession number.