Fossil forms are also restricted almost exclusively to Africa, although a few specimens of the Pleistocene species Cryptomys asiaticus have been found in Israel.

Blesmols, like many other fossorial mammals, have greatly reduced eyes and ear pinnae, a relatively short tail, loose skin, and (aside from the hairless naked mole rat) velvety fur.

Research has shown that at least two species of blesmol (Fukomys mechowii and Heliophobius argenteocinereus) are not blind, as commonly believed, and will actively avoid blue or green-yellow light.

The ability to sense the presence of light is probably useful in allowing them to detect breaches in their tunnel systems and repair them promptly.

The medial masseter muscle shows only minimal passage through the infraorbital foramen leading most authorities to consider them protrogomorphous.

[citation needed] These species are characterized by having a single reproductively active male and female in a colony where the remaining animals are sterile.

They generally have small litters of two to five young, perhaps because their environment is sufficiently safe that they do not need to rapidly replace their population as many other rodents do.

Like other fossorial rodents such as pocket gophers, tuco-tucos, and blind mole rats, blesmols appear to speciate rapidly.