Samuel L Miller, Nam Lu, Payton R Shears, Jacobey King, Krithivasan Sankaranarayanan, Paul A Lawson
Bats, of the order Chiroptera, comprise over 1,400 species and account for over 21% of all currently described mammalian species. However, despite this huge group of mammals, a remarkably small number of bacterial species have been described from this group. In a continuing study of non-human mammals, dozens of strains were isolated from anaerobic guano-pile enrichments collected in a bat cave near Protem, MO, USA. Of these, two novel taxa were identified and designated BS-2T and BS-20T; both were rod-shaped, Gram-stain-positive bacteria. Phylogenetic analysis of the 16S rRNA gene and phylogenomic analysis placed BS-2T within the genus Lacrimispora, and BS-20T was located within the family Jonesiaceae, but with no particular affiliation to any genus. Overall genomic-based relatedness indices indicated that strains BS-2T and BS-20T shared average nucleotide identity and digital DNA-DNA hybridization values <95.0% and <70.0% with their nearest neighbouring taxa, which are the currently accepted thresholds for species-level delineation. Further, for strain BS-20T, genus-specific delineation indices demonstrated a shared average amino acid identity, and percentages of conserved proteins were <68.0% and <42.0%, respectively, between BS-20T and other Jonesiaceae taxa, below commonly accepted genus-level delineation thresholds. The predominant cellular fatty acid of isolate BS-2T was C16:0, whereas BS-20T contained C15:0 anteiso and C14:0 as the predominant cellular fatty acids. The G+C content of BS-2T and BS-20T was 44.1 and 56.5 mol%, respectively. Based on biochemical, phylogenetic, genotypic and chemotaxonomic criteria, strains BS-2T and BS-20T represent novel isolates within the genus Lacrimispora and family Jonesiaceae, for which the names Lacrimispora cavernae sp. nov. and Aleya cavernae gen. nov., sp. nov. are proposed. Strains BS-2T (=NRRL B 65694T=CCUG 77247T=CCM 9410T) and BS-20T (=NRRL B-65699T=CCUG 77269T) are proposed as the type species of these novel taxa.