| argentina | buenos aires city | candidatus microthrix | genus | 0 | 1 |
| argentina | buenos aires province | candidatus microthrix | genus | 0 | 1 |
| australia | new south wales | candidatus microthrix | genus | 0 | 1 |
| australia | queensland | candidatus microthrix | genus | 0 | 1 |
| australia | south australia | candidatus microthrix | genus | 0 | 2 |
| brazil | parana | uncultured candidatus microthrix sp. | species | 1 | 0 |
| canada | nunavut | candidatus microthrix sp. uba4742 | species | 1 | 0 |
| china | | candidatus microthrix parvicella | species | 6 | 0 |
| china | | uncultured candidatus microthrix sp. | species | 2 | 0 |
| french polynesia | | candidatus microthrix | genus | 0 | 1 |
| germany | berlin | candidatus microthrix | genus | 0 | 1 |
| luxembourg | | candidatus microthrix parvicella | species | 4 | 0 |
| luxembourg | | candidatus microthrix sp. uba7237 | species | 1 | 0 |
| malaysia | sabah | candidatus microthrix | genus | 0 | 1 |
| mexico | colima | candidatus microthrix sp. uba3125 | species | 1 | 0 |
| mexico | colima | candidatus microthrix sp. uba7903 | species | 1 | 0 |
| mexico | yucatan | uncultured candidatus microthrix sp. | species | 1 | 0 |
| netherlands | | candidatus microthrix parvicella bio17-1 | no rank | 14 | 0 |
| south africa | kwazulu-natal province | candidatus microthrix parvicella | species | 1 | 0 |
| south africa | the western cape province | candidatus microthrix parvicella | species | 1 | 0 |
| united states | wisconsin | uncultured candidatus microthrix sp. | species | 3 | 0 |