The Iberian worm lizard is locally known as cobra-cega (Portuguese), culebrilla ciega (Spanish), and colobreta cega (Catalan),[3] all meaning "blind snake".

Recent studies into the mitochondrial and nuclear genomic data of 47 isolated B. cinereus populations show rather large sequence divergence between two apparent clades, leading some researchers to call for a division of the Iberian worm lizard into two species.

By using its habitat, the Iberian worm lizard is able to maintain a constant body temperature with minimal energy expense.

[7] The Iberian worm lizard is believed to be an opportunistic feeder through the study of central Spanish B. cinereus populations.

B. cinereus is also believed to have low energy requirements based on average stomach content in comparison with other lizard species.

[9] Due to its subterranean lifestyle, the Iberian worm lizard exhibits characteristically small, primitive eyes.

[10] Cotton swabs exhibiting prey specific chemical indicators elicit tongue flick responses by the B. cinereus.

[10] Cotton swab studies emitting predatory chemosensory signals have also been performed in order to quantify the Iberian worm lizard's anti-predatory response mechanisms.

Swabs exhibiting signals from predators like the southern smooth snake, Coronella girondica, the scolopendromorph centipede (Scolopendra), and the Bedriaga's skink, Chalcides bedriagai were all tested.

High rates of tongue flicks were seen for all three predator chemicals with defensive biting by B. cinereus subjects on the swabs smelling like snake or centipede.

While a conclusive statement cannot be made about the hierarchy of predators based on tongue flicks, the self-defense response would indicate the skink as being the greatest threat to B.

While morphological characteristics are less defined between the two proposed clades, the genetic variation is incontrovertible and significant enough to make gene flow unlikely.