The type specimen was collected from a fisherman's seine net at the Red Bank community in West Deptford Township, New Jersey.

They found considerable differences and evolutionary divergence, and suggested that the offshore ecotype be retained within T. truncatus while T. erebennus was resurrected as the scientific name for the nearshore type.

To choose the common name, Costa et al. consulted with the Nanticoke Lenni-Lenape tribal nation, who are descendents of the people originally inhabiting the area where the holotype was collected.

They are known to inhabit nearshore coastal waters, including bays and estuaries, in the eastern United States from New York to Florida.

Additionally, they are genetically related to coastal bottlenose dolphin populations in the Caribbean Sea and Gulf of Mexico,[3] and may inhabit these waters as well.