Characteristics & Similar species
Like other members of the Clusiodes albimanus species group, C. niger is characterized by three pairs of dorsocentral bristles and partially white fore tarsi. It can be separated from other Nearctic members of the group by its dark overall colouration. It is closest in appearance to the more common and widespread C. johnsoni, which can only be separated on the basis of colour. These two taxa may eventually prove to belong to the same species.

Distribution
Clusiodes niger (C. nigrus or C. nigra prior to 2008) is a very uncommon species restricted to the southern and eastern United States, and is known from only three individuals.