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Short answer
LPSN, the List of Prokaryotic names with Standing in Nomenclature, is a free online database of bacterial and archaeal names, hosted by the DSMZ. It records names validly published under the International Code of Nomenclature of Prokaryotes (ICNP) and shows which name is correct and where type strains are deposited.
This page is for researchers and lab staff who meet an unfamiliar organism name in a paper, a culture collection record or a manuscript and need to know how to check it. It is general reference information; it is not taxonomic or biosafety advice for a specific organism.
Definition and scope
The LPSN home page describes the resource as providing “comprehensive information on the nomenclature of prokaryotes”. It was founded by Jean P. Euzeby in 1997 as the List of Bacterial names with Standing in Nomenclature, went onto the web on 28 January 1998, and passed to Aidan C. Parte in July 2013. The DSMZ acquired it in November 2019, and the current database, launched on 17 February 2020, merged LPSN with the DSMZ Prokaryotic Nomenclature Up-to-date (PNU) service (Parte et al. 2020). Euzeby died on 27 October 2025, according to the LPSN home page.
Users can browse taxa from domain down to species, including rarely used categories, run an advanced search, and consult a List of Recommended Names for bacteria of medical importance. LPSN is designated a Global Core Biodata Resource (since December 2023) and an ELIXIR Core Data Resource (since January 2026), per its home page.
Types or related concepts: ICNP, ICSP and LPSN
Three different things are easily confused:
- ICNP is the rulebook. The ICSP publishes the International Code of Nomenclature of Prokaryotes, which “regulates how all prokaryotes are named”.
- ICSP (formerly the International Committee on Systematics of Bacteriology) is the committee that represents the interests of all microbiological disciplines with respect to prokaryote nomenclature; its Judicial Commission issues opinions on the Code.
- LPSN is the database that records names published in line with the Code and presents their status. It is a curated service, not the Code itself.
For sequence-database taxonomy maintained by a different organisation, see the CASRAI guide to NCBI Taxonomy.
How it works: reading an LPSN entry
A taxon page, as described by Parte et al. (2020), combines the following fields:
- the name and its authority (author or authors and year of valid publication);
- category and kind of proposal (for example sp. nov.), etymology and gender;
- type strain accession numbers that link to culture collections and BacDive, a TYGS button, and links to 16S rRNA gene sequences at ENA and NCBI;
- the effective publication, plus the IJSEM Validation List or Notification List for names published outside the International Journal of Systematic and Evolutionary Microbiology;
- nomenclatural status and taxonomic status (a synonym points to its correct name);
- risk group, given according to the German TRBA 466;
- notes, and the parent taxon with the publication that assigned it.
Reading key for the typography
| How the name appears | What it means (Parte et al. 2020) |
|---|---|
| Bold italic | A correct name |
| Italic only | A name not considered correct |
| Italic in quotation marks | A name that is not validly published |
| Square brackets | Nomenclatural status is unreliable or uncertain, for example an artificial parent node of an incertae sedis taxon, or a Candidatus species whose genus has not been described |
A checklist for checking a name
- Search the name. The taxonomy search finds any phrase of four or more letters in a taxon name.
- Check nomenclatural status: was the name validly published, and is it legitimate?
- Check taxonomic status: if the name is a synonym, follow it to the correct name.
- Read the type strain entry and the culture collection accession numbers before citing a strain.
- Record the date you accessed the page. LPSN asks users to state the access date when citing it.
Where it matters for labs
- Naming in manuscripts and records. Correct names are selected by the curators on the basis of valid publication, legitimacy and priority (Principle 6), and only correct names are to be used (Rule 23a Note 5), according to Parte et al. (2020). Checking a name before submission avoids using a synonym or a name without standing.
- Strain deposit. The advanced search can filter by strain deposit, using the culture collection and number, as well as by authority, etymology, category, nomenclatural type, validly published, Candidatus and correct name.
- Risk group. An entry shows a risk group under Germany’s TRBA 466. This is a German regulation; it is not the same instrument as the biosafety levels used elsewhere. For the US framework see the CASRAI term biosafety level (BSL), and confirm the classification that applies at your institution.
- Sequence-based work. For sequence records and reference data see NCBI Reference Sequence; for the discipline background see what is bacteriology.
Common misunderstandings
- “The newest validly published name is the correct name.” Parte et al. (2020) state that the ICNP does not specify that the most recent validly published name is to be regarded as the correct name. The curators’ choice reflects one taxonomic opinion in the literature, and alternative arrangements are indicated.
- “LPSN is the Code.” The Code is the ICNP, published by the ICSP. LPSN is a database that applies it.
- “A name in italics is fine to use.” Italics alone mark a name that is not considered correct; only bold italic marks a correct name.
- “The risk group is universal.” The risk group shown is the one in the German TRBA 466.
FAQ
What does LPSN stand for?
List of Prokaryotic names with Standing in Nomenclature. It began in 1997 as the List of Bacterial names with Standing in Nomenclature.
Who runs LPSN?
It is hosted by the DSMZ and supported by the ICSP; the DSMZ took it over in November 2019.
How do I cite LPSN?
The site asks users to give the access date. For the List of Recommended Names it gives Goeker M et al. 2025, Int J Syst Evol Microbiol 75:6943, doi 10.1099/ijsem.0.006943. For other uses, including the API, it gives Freese HM et al. 2026, Nucleic Acids Res 54:D884-D891, doi 10.1093/nar/gkaf1110. The move to the DSMZ is described in Parte et al. 2020, doi 10.1099/ijsem.0.004332.
Sources
- LPSN home page, lpsn.dsmz.de, read 2026-11-08.
- Parte AC, Sarda Carbasse J, Meier-Kolthoff JP, Reimer LC, Goeker M. LPSN moves to the DSMZ. Int J Syst Evol Microbiol 2020;70(11):5607-5612. doi 10.1099/ijsem.0.004332 (PMC7723251), read 2026-11-08.
- International Committee on Systematics of Prokaryotes, the-icsp.org, read 2026-11-08.
