Cristitectus is a genus of parasitic nematodes, belonging to the family Cystidicolidae.

Species of Cristitectus are parasitic as adults in the gastrointestinal tract of fish.

The genus Cristitectus is characterised by short cuticular ridges located on the anterior end.

[1] Cristitectus congeri was described from a single female, 24 mm in length.

[1] The etymology is not detailed in the original publication[1] but it can be inferred that the root "crist" in the name refers to the characteristic anterior cristae or ridges.