Sortumariski

Sortumariski is a monotypic genus of aquatic protists described in 2020 by researchers studying polar freshwater ecosystems. The genus contains a single species, Sortumariski arctica, known from cold streams and meltwater pools in the Arctic and at high elevations.

Taxonomy and name: The name Sortumariski derives from Latin roots interpreted as “sorted sea,” combined with the suffix -ski to honor a prominent microbiologist. The taxonomic placement has been variable; some sources place it among amoebozoan-like protists, others in a looser grouping of aquatic algae, reflecting ongoing debate about its affinities.

Description: Sortumariski arctica forms small, semi-transparent colonies up to about 2 cm in diameter. Colonies are composed of branching filaments and a network of plasmodial tissue. Colors range from pale green to olive, with motile spores produced in discrete sporocarps under certain conditions.

Habitat and distribution: It has been found in subglacial streams, cold meltwater pools, and high-altitude rock pools, often on mineral substrata or detritus. It appears adapted to low temperatures, variable light, and fluctuating water availability, with populations clustered seasonally.

Ecology and life cycle: The organism exhibits a biphasic life cycle with a plasmodial phase and a sporocarp phase. Reproduction releases spores into water, enabling dispersal. It interacts with microbial communities, including bacteria and algae, in mutualistic and commensal relationships.

Research and significance: Sortumariski arctica is of interest as a potential bioindicator for cold-water ecosystems and for studies of adaptation to extreme environments. Phylogenetic placement remains unsettled, with ongoing molecular analyses aimed at clarifying its relationships to related protist groups.