Testing the Habitat Selectivity of Bdelloid Rotifers in a Humid Area; National Park of Chrea (Algeria)

Rotifers of the Order Bdelloidea occupy a large number of terrestrial and aquatic humid habitats from the Tropic to Antarctic regions. In this study, differences in species richness and composition among six sampled habitats (soil, roots, bark, plant, lichen, and moss) were tested to understand the biodiversity pattern of bdelloid rotifers. A total of 90 samples were collected from The National Park of Chrea (NPC), one of the most important humid areas in the north of Algeria, from six different sites in the winter of 2019. The samples were stored in a dry room and hydrated in a petri dish using distilled water. After the sampling, bdelloid taxa were observed under a microscope alive and identified using specific keys. Twelve species of bdelloids belonging to six genera and two families were found from the 2469 individuals analyzed in the different samples. Species richness for each sample ranged from 1 to 7 and was significantly different among habitats (ANOVA: F5,72 = 14.04, P < 0.0001). In the moss, soil, and bark habitats, Adineta vaga was the dominant species. In the lichen habitats, Philodina sp. was the dominant species, due to a small variation in factors such as temperature and dryness. This shows that the bdelloids do not exist only in the freshwater habitats but also in the terrestrial habitats and that microorganisms may have biodiversity and habitat preferences.