Thaumastoderma heideri (Greek; Thauma: a wonder, Derma: skin) belongs to the phylum Gastrotricha and the order Macrodasyida, which are worm shaped, mainly marine species of meiofauna.

They live in coarser sand and like the rest of the gastrotrichs their movement is very slow.

The family Thaumastodermatidae includes more than 130 species and it can be found widely across the globe.

[2] The species is widely distributed in marine environments in European waters, parts of the North Atlantic, the Indian Ocean and the Mediterranean Sea.

It lives in shallow waters (< 400 meters) and areas with a sandy ocean bed.