The Typhloplanidae are mainly small flatworms (size range 1-5 mm). Few bigger ones (e.g. Mesostoma ehrenbergii) may reach up to 1.5 cm in length. There are ±300 species living in a variety of aquatic habitats with a preference for freshwater or estuarine habitats. Few species are marine or terrestrial. They live on the bottom between sand grains, in the aquatic vegetation or they are pelagic. They are predators on the microbiota (from protozoa to microcrustacea). They have received attention for being predators of mosquito larvae and planktonic crustaceans (Tranchida et al., 2009, Dumont et al., 2014 and references therein). Typhloplanids have different strategies for capturing their prey; quite a few form traps and threads of mucus. Some species suspend on a mucus thread in the water while waiting to attack prey. Mesostoma lingua produces a poisonous neurotoxin enclosed in the mucus that causes the paralysis of prey. This temperature-dependent toxin is delivered through contact or diffusion (Case and Washino, 1979; Schwartz and Hebert, 1982; Dumont and Carels, 1987). The morphological and ecological diversity, as well as the high number of species and the great densities that they can develop in their habitat, make the study of this taxon valuable and necessary.weiterlesen