Filker, et al (2014): Rod-shaped archaeon with a length-width ratio of 3:1. Epibiont on the scuticociliate Platynematum salinarum (Ciliophora, Scuticociliatia). Phylogenetically related to Hlm. pelagica on the basis of the 16S rRNA gene sequence (accession number: KF736828), and identifiable with the specific FISH oligonucleotide probes Hesr1-2 (Hesr1: 5′-TTCACTAGGTGTTCCTCTCG-3′; Hesr2: 5′-GACTCTTCGGAGTGGTGTTAT-3′) and the archaeal-specific probe Arch915 (5′-GTGCTCCCCCGCCAATTCCT-3′). Identified as an inhabitant on the surface of a P. salinarum population, isolated from the Ria Formosa solar saltern in Faro, Portugal. Anisomycin experiments point to an obligate symbiotic relation with its host, whereas no free-living forms have been observed. Uncultured so far.
Filker (2021): 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 μm2. Free-living forms were not observed. Candidatus Halectosymbiota riaformosensis is sensitive to anisomycin. Known habitats are aquatic hypersaline environments.