An epibiosis between ciliate Vorticella spp. and the roots of aquatic plant Lemna minor in a freshwater pond proved that ciliates generally employing them as an anchor substrate while at the same time filtering suspended particles from the passing water. The duckweed is floating aquatic plants that offer lush microbial fauna to the ciliates. This association shows a commensal relationship, in which Vorticella spp. adhere to duckweed roots as a substrate for colonization and thereby gain access to a nutrient-rich microhabitat of pond water and strain food particles without any damage to aquatic weeds, but duckweed does not seem to derive any direct advantage from the association with Vorticella spp. Number and size of duckweed roots influence the colonization of ciliates, both in cluster and solitary. The present observational study confirms that Vorticella spp. has a permanent epibiotic association with roots of Lemna minor in freshwater ponds. Colonies and single individuals are present in different root lengths (11–27 mm), with longer roots having more individuals based on larger attachment and aggregation surface area. Root length does not limit colonization; short and long roots are both effective substrates for attachment. The widely and uneven distribution of clustered colonies suggests cooperative advantages such as efficient feeding and defence. In general, Vorticella exists as an opportunistic epibiont on the duckweed root, which is ecologically significant for a renewable habitat for protozoan ciliates.