Register list for Penumbrarchaeum helgolandensis gen. nov. sp. nov. and their lineage

Submitted by Maeke, Mara

Class Penumbrarchaeia

Etymology: [Pe.num.brar.chae'i.a] N.L. neut. n. Penumbrarchaeum, referring to the type genus Penumbrarchaeum; -ia, ending to denote a class; N.L. neut. pl. n. Penumbrarchaeia, the Penumbrarchaeum class
Nomenclatural type: Genus Penumbrarchaeum
Description: The description is the same as for Candidatus Penumbrarchaeum gen. nov. with the following additions: Candidatus Penumbrarchaeia class. nov. comprises the type order Candidatus Penumbrarchaeales ord. nov. and Order 2, Order 3 and Order 4, three previously unidentified orders in this class. Members of Order 3 and Order 4 are anaerobes inhabiting the water column of oxygen minimum and oxygen deficient zones, not capable of protein degradation based on metabolic potential.
Classification: Archaea » Thermoplasmatota » Penumbrarchaeia
References: Effective publication: Maeke et al., 2025 [1]
Registry URL: https://seqco.de/i:49913

Order Penumbrarchaeales

Etymology: [Pe.num.brar.chae.a'les] N.L. neut. n. Penumbrarchaeum, referring to the type genus Penumbrarchaeum; -ales, ending to denote an order; N.L. fem. pl. n. Penumbrarchaeales, the Penumbrarchaeum order
Nomenclatural type: Genus Penumbrarchaeum
Description: The description is the same as for Candidatus Penumbrarchaeum gen. nov. with the following additions: Candidatus Penumbrarchaeales ord. nov. was previously known as “EX4484-6” and comprises two families Candidatus Penumbrarchaeaceae fam. nov. and Family 1B, previously known as “EX4484-36”.
Classification: Archaea » Thermoplasmatota » Penumbrarchaeia » Penumbrarchaeales
References: Effective publication: Maeke et al., 2025 [1]
Registry URL: https://seqco.de/i:49914

Family Penumbrarchaeaceae

Etymology: [Pe.num.brar.chae.a'ce.ae] N.L. neut. n. Penumbrarchaeum, referring to the type genus Penumbrarchaeum; -aceae, ending to denote a family; N.L. fem. pl. n. Penumbrarchaeaceae, the Penumbrarchaeum family
Nomenclatural type: Genus Penumbrarchaeum
Description: The description is the same as for Candidatus Penumbrarchaeum gen. nov. with the following additions: Candidatus Penumbrarchaeaceae was previously known as the family “EX4484-6”. Members of the family were inferred to be found in sediments of marine and freshwater origin as well as cold seeps. Type genus: Candidatus Penumbrarchaeum gen. nov.
Classification: Archaea » Thermoplasmatota » Penumbrarchaeia » Penumbrarchaeales » Penumbrarchaeaceae
References: Effective publication: Maeke et al., 2025 [1]
Registry URL: https://seqco.de/i:49915

Genus Penumbrarchaeum

Etymology: [Pe.num.brar.chae'um] N.L. fem. n. penumbra, partial shadow as in partially hidden; N.L. neut. n. archaeum, ancient one, archaeon; N.L. neut. n. Penumbrarchaeum, the archaeon hidden in the biosphere at the edge of detection
Nomenclatural type: Species Penumbrarchaeum helgolandense^Ts
Description: Inferred to be of marine sediment origin, an anaerobe fermenting proteins, peptides and amino acids. Members were of low abundance (< 0.32%) and thus classified as rare biosphere.
Classification: Archaea » Thermoplasmatota » Penumbrarchaeia » Penumbrarchaeales » Penumbrarchaeaceae » Penumbrarchaeum
References: Effective publication: Maeke et al., 2025 [1]
Registry URL: https://seqco.de/i:49916

Species Penumbrarchaeum helgolandense^Ts

Etymology: [hel.go.lan.den'se] N.L. neut. adj. helgolandense, of Helgoland, the region where the Helgoland mud area is located in the North Sea, and this organism originated from
Nomenclatural type: NCBI Assembly: GCA_965234725.1 ^Ts
Description: Inferred to be of marine sediment origin, an anaerobe fermenting proteins, peptides and amino acids. Members were of low abundance (< 0.32%) and thus classified as rare biosphere. The species is represented by the MAG (metagenome-assembled genome) E3_1_d157 (3.46 Mbp), obtained from metagenomic sequences retrieved from an enrichment of Helgoland mud area sediment (54°05’15.5’’N, 7°58’05.5’’E) from a sediment depth of 45-70cm.
Classification: Archaea » Thermoplasmatota » Penumbrarchaeia » Penumbrarchaeales » Penumbrarchaeaceae » Penumbrarchaeum » Penumbrarchaeum helgolandense^Ts
References: Effective publication: Maeke et al., 2025 [1]
Registry URL: https://seqco.de/i:49912

References

Maeke et al. (2025). Extensive data mining uncovers novel diversity among members of the rare biosphere within the Thermoplasmatota. Microbiome. DOI:10.1186/s40168-025-02140-8

Register List Certificate of Validation

On behalf of the Committee on the Systematics of Prokaryotes Described from Sequence Data (SeqCode Committee), we hereby certify that the Register List seqco.de/r:zcce2eqc submitted by Maeke, Mara and including 5 new names has been successfully validated.

Date of Priority: 2025-07-15 11:06 UTC

DOI: 10.57973/seqcode.r:zcce2eqc