Mesostoma ehrenbergii is a species of rhabdocoel flatworms in the family Typhloplanidae.

[1] The species is comparatively large for microturbellarians,[2] reaching 1,5 cm[3] in body length.

It is dorsoventrally flattened with the anterior end gradually tapering and broadly pointed, and the posterior end sharply pointed.

[5] The species has been recorded in Argentina, Brazil, Europe, Iran, Kenya, Kyrgyzstan, New Zealand, Peru, Siberia, Trinidad, and the USA.

[2] The animal primarily feeds on cladocerans, but also on fairy shrimps, naidid oligochaetes, large rotifers and mosquito larvae.