see text Tetrameridae is a family of spirurian nematodes.

It is the smallest of the large genera making up the bulk of the superfamily Habronematoidea.

This family contains the largest known nematode: Placentonema gigantissima is several meters long and has been found in the placenta of the sperm whale (Physeter macrocephalus).

[1] The Tetrameridae number about half a dozen genera only, but some are rather speciose; the type genus Tetrameres contains a lot of species even by nematode standards.

While it might be overlumped, as presently delimited about half of the more than 100 species of Tetrameridae are placed in it.