Abstract
Hal.ec.to.sym.bi.o'ta. Gr. masc. n.
hals
,
halos
salt, salt water; Gr. prep.
ektos
outside; N.L. masc. n.
symbiota
(from Gr. n.
symbiotes
) one who lives with a companion, partner; N.L. masc. n.
Halectosymbiota
an ectosymbiont from salt water organisms.
The genus
Candidatus
Halectosymbiota corrig., originally described as
Ca
. Haloectosymbiotes, was established based on a 16S rRNA taxonomic marker gene sequence of the only identified species in this genus,
Candidatus
Halectosymbiota riaformosensis.
Ca
. Halectosymbiota riaformosensis was observed to live as ectosymbiont on a halophile scuticociliate, which was isolated from a thalassohaline solar saltern pond (12% salinity) in Faro, Portugal. Comparisons of 16S rRNA gene sequences showed that
Ca
. Halectosymbiota is phylogenetically affiliated to the genera
Halolamina
(sequence similarity to
H. pelagica
: 87%) and
Halobaculum
(sequence similarity to
H. magnesiiphilum
85%). Based on scanning electron microscopy micrographs and fluorescence
in situ
hybridization, cells are rod‐shaped and approximately 1.8 × 0.6 μm in size. Cells are densely covering the surface of the host, with approximately 0.52 epibiotic cells per μm
2
. Free‐living forms were not observed.
Candidatus
Halectosymbiota riaformosensis is sensitive to anisomycin. Known habitats are aquatic hypersaline environments.
Type species
: Not applicable.
Taxonomic and Nomenclature Notes
According to the List of Prokaryotic names with Standing in Nomenclature (LPSN), the taxonomic status of the genus
Candidatus Halectosymbiota
is: preferred name (not correct name) (last update, February 2025)
*
.
LPSN classification:
Archaea
/
Methanobacteriati
/
Methanobacteriota
/
Halobacteria
/
Halobacteriales
/
Halobacteriaceae
/
Candidatus Halectosymbiota
Candidatus Halectosymbiota
could not be recovered in GTDB
**
.
*
Meier‐Kolthoff
et al. (
2022
).
Nucleic Acids Res
,
50
,
D801
–
D807
; DOI:
10.1093/nar/gkab902
**
Parks
et al. (
2022
).
Nucleic Acids Res
,
50
,
D785
–
D794
; DOI:
10.1093/nar/gkab776