Tmesiphantes crassifemur is a species of theraphosine theraphosid spider.

[1] In 1960, Berta Gerschman de Pikelin and Rita Schiapelli described this species as Melloleitaoina crassifemur.

In 1993, Gunter Schmidt transferred the species to Dryptopelma, but this was rejected by Fernando Pérez-Miles in 1996.

It is characterized by a very curved embolus without any triangular tooth.

The prolateral inferior embolar keel is just as long as the prolateral superior and the apex of the embolus is widened.