Abstract
Genetic and phenotypic characteristics of the possible agent of epizootic bovine abortion, the Ornithodoros coriaceus spirochete, revealed that this organism is a new species of Borrelia. We propose the name Borrelia coriaceae for this species. The type strain of B. coriaceae is strain Co53 (= ATCC 43381). The guanine-plus-cytosine content of the deoxyribonucleic acid of the type strain was determined to be 32.4 mol% (thermal denaturation method).