Hummelinck's laucha is a small rodent known from northern South America and Caribbean islands. One additional specimen was recorded in a savanna in northern Brazil.
Its back is grayish orange and its underside is mostly white. Pale buff spots occur behind the ears, and the tail is faintly two-colored.
The additional northern Brazilian record came from savanna with grasses on rocky hillocks and sparse vegetation around them. One site does not establish a species-wide habitat preference.
An extinction-risk assessment has not been added yet.