Species, the fundamental units of taxonomy, have to be described according to the rules outlined in the ICZN-Code. However, the current requirements for species description need to be adjusted to modern demands. This can be achieved by implementing: 

1.) Species diagnoses that are based on differences in nucleic acid sequences, allowing to distinguish new species from their closest relatives; genetic data need to be supplemented by phenotypic data to ensure the integration into existing reference systems. The quest for molecular data should be manifested. 

2.) A provisional status should be accepted for partially characterised species (“candidate species” or “operational taxonomic units”). 

For the time being, I would advise taxonomists against describing new species or making species-level revisions until a universally applicable species-rank delimitation method is agreed upon. 

References/Literature

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Zamani A, Faltynek Fric Z, Gante HF, Hopkins T, Orfinger AB, Scherz MD, Sucháčková Bartonová A, and Dal Pos D (2022), DNA barcodes on their own are not enough to describe a species, Syst. Ent. (pdf)