fastANI ANI of > 95% between known distinct species #136
Description
I have a clarification question on interpreting results or perhaps optimizing the fastANI analysis. I used fastANI (v.1.33) to generate pairwise ANI values for a cohort of 12 Nocardiopsis genomes using all default parameters. The genomes in question were type strains deposited to DSMZ and retrieved from NCBI. My question involves ANI values between several of these type strains:
Nocardiopsis valliformis (DSM 45023) and Nocardiopsis exhalans (JCM 11759), ANI of 96.16%, frag count: 1986, alignment length: 2337
Nocardiopsis metallicus (DSM 44598) and Nocardiopsis exhalans (JCM 11759), ANI of 95.52%, frag count: 2102 alignment length: 2591
Does anyone have any insight into why I am observing ANI values above the species threshold for these strains?