Like all glyptodonts, Trachycalyptus had a heavy body protected by a sturdy armor composed of osteoderms fused together.

It had wrinkled and strongly punctuated osteoderms; the central figure was mainly distinguished by a lower density of small holes on its surface.

The tail was protected by a caudal tube, characterized by the presence of wrinkled osteoderms with numerous vascular perforations, without differentiation of the peripheral area.

The genus Trachycalyptus was first described in 1908 by Florentino Ameghino, based on fossil remains found in Pliocene terrains of Argentina.

Trachycalyptus was a member of the glyptodont Sclerocalyptini; it was originally considered closely related to the genus Urotherium; however, it was recently placed closer to the genera Lomaphorus and Neosclerocalyptus.