Two novel bacterial taxa, Photorhabdus machadonis sp. nov., represented by strain SF281T, isolated from Heterorhabditis safricana SF281, and Photorhabdus laumondii subsp. malanae subsp. nov., represented by strain MH8.4T, isolated from Heterorhabditis sp. eMH8.4TH, are described. Phylogenetic reconstruction using 16S rRNA shows that P. machadonis sp. nov. SF281T is closely related to Photorhabdus cinerea DSM 19724T, whereas P. laumondii subsp. malanae subsp. nov. MH8.4T is closely related to P. laumondii subsp. laumondii TT01T and P. laumondii subsp. clarkei BOJ-47T. Phylogenetic reconstruction using whole-genome sequences shows that P. machadonis sp. nov. SF281T is closely related to Photorhabdus tasmaniensis DSM 22387T, Photorhabdus viridis GreenT, Photorhabdus thracensis DSM 15199T and Photorhabdus temperata DSM 14550T, and P. laumondii subsp. malanae subsp. nov. MH8.4T is closely related to P. laumondii subsp. laumondii TT01T and P. laumondii subsp. clarkei BOJ-47T. Digital DNA–DNA hybridization (dDDH) values between P. machadonis sp. nov. SF281T and its four closest relative species P. tasmaniensis DSM 22387T, P. viridis GreenT, P. thracensis DSM 15199T and P. temperata DSM 14550T are 48%, 54%, 52% and 51%, respectively. dDDH values between P. laumondii subsp. malanae subsp. nov. MH8.4T and its two closest sister species P. laumondii subsp. laumondii TT01T and P. laumondii subsp. clarkei BOJ-47T are 73% and 79%, respectively. The biochemical capacities of the novel taxa also differ from those of their more closely related taxa. Given the clear phylogenetic separation, the sequence divergence values and the phenotypic differences, we conclude that (i) strain SF281T represents a novel bacterial species, for which we propose the name P. machadonis sp. nov. with SF281T (=CCM 9463T=CCOS 2127T) as the type strain, and (ii) strain MH8.4T represents a novel bacterial subspecies, for which we propose the name P. laumondii subsp. malanae subsp. nov. with MH8.4T (=CCM 9440T=CCOS 2126T) as the type strain

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