It is named after the latin 'furvus' meaning 'dark complexion' or 'swarthy', referring to the colouration of the subspecies.

[1] It is found on the San Quentin Plain in Baja California del Norte - due to the area's restricted and largely inaccessible habitat not much is known about the subspecies.

Specifically, C. e. furvus is the only subspecies of the species to display subfoveal scales.

[3] The Rosario rattlesnake is thought to eat mostly small mammals, using burrows to hunt and for shelter.

[4] The dusky Baja California rattlesnake is known to give birth to less than ten neonates in one brood.