Valediction: descriptions of novel prokaryotic taxa published in Antonie van Leeuwenhoek—change in editorial policy and a signpost to the future?

Out with the old and in with the new: time to rethink twentieth century chemotaxonomic practices in bacterial taxonomy

Chemotaxonomic methods played an important role in the development of the polyphasic approach to classification of Archaea and Bacteria. However, we here argue that routine application of these methods is unnecessary in an era when genomic data are available and sufficient for species delineation. Thus, authors who choose not to utilize such methods should not be forced to do so during the peer review and editorial handling of manuscripts describing novel species. Instead, we argue that chemotaxonomy will thrive if improved analytical methods are introduced and deployed, primarily by specialist laboratories, in studies at taxonomic levels above the characterisation of novel species.

Addressing the sublime scale of the microbial world: reconciling an appreciation of microbial diversity with the need to describe species

There are fewer than 20,000 prokaryotic species with validly published names, meaning >99% of a reasonable estimate of microbial diversity remains formally unnamed. Here we explore the damaging consequences of the current practice in which each new species is described in a standardized publication, most typically a 'single strain species description'. This approach is both an impediment to scaling up progress in naming the microbial world and also a significant factor in the poor reputation of the discipline of microbial taxonomy. We conclude that significant changes in author habits are needed and make constructive suggestions as to how author practice should adapt.

Proposed nomenclature or classification changes for bacteria of medical importance: taxonomic update 5

A key aspect of medical, public health, and diagnostic microbiology laboratories is the accurate identification and rapid reporting and communication to medical staff regarding patients with infectious agents of clinical importance. Microbial taxonomy continues to change at a very rapid rate in the era of molecular diagnostics including whole genome sequencing. This update focuses on taxonomic changes and proposals that may be of medical importance from 2018 to 2020.

Salinigranum halophilum sp. nov., isolated from marine solar salterns

Three halophilic archaeal strains, YJ-53T, ZS-5 and DYF38, were isolated from marine solar salterns located in different provinces of China. The three strains formed a single cluster (99.7–99.8 and 97.9–99.2 % similarities, respectively) that was separate from the current two members of Salinigranum (96.7–98.0 and 89.8–92.9 % similarities, respectively) on the basis of 16S rRNA and rpoB′ gene sequence comparisons and phylogenetic analysis. Diverse phenotypic characteristics differentiated strains YJ-53T, ZS-5 and DYF38 from Salinigranum rubrum GX10T and Salinigranum salinum YJ-50-S2T. The major polar lipids of isolated strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two major glycolipids chromatographically identical to mannosyl glucosyl diether and sulfated mannosyl glucosyl diether, detected in the current members of Salinigranum . The OrthoANI and in silico DNA–DNA hybridization (DDH) values between the three strains were in the range of 97.7–98.4 % and 80.3–86.1 %, respectively, much higher than the threshold values proposed as species boundaries (average nucleotide identity 95–96 % and in silico DDH 70 %), revealing that the three strains represent one species. Results of comparative OrthoANI and in silico DDH analyses of the strains described in this study with validly described members of the genus Salinigranum supported that strains YJ-53T (=CGMCC 1.12860T=JCM 30238T), ZS-5 (=CGMCC 1.12867=JCM 30240) and DYF38 (=CGMCC 1.13779=JCM 33557) represent a novel species of the genus Salinigranum , for which the name Salinigranum halophilum sp. nov. is proposed.