This animal is known only from its leg and feet bones. "Velocisaurus" was probably around 1.2 meters long (4 ft). The foot is unique in that the middle (third) metatarsal (foot bone) was the main weight-bearing element. Its upper end has thickened and the shafts of the adjoining second and fourth metatarsals have thinned considerably. Such a condition is unknown for other theropods, including birds, but a similar set-up occurred in three-toed horses (like "Mesohippus"). José Bonaparte explained it as an adaptation for a cursorial (running) lifestyle. He suggested that "Velocisaurus" was itself an omnivore, because the sole claw found, of the fourth toe, was not curved, but relatively straight.