Physical 

 Mud Dog Whelks are primarily dark brown to black, with white patches or stripes. They reach little over 2.5 cm in length, and are usually found in groups and various sizes.

Habitat

N. oboletus prefer intertidal mud flats. They can be found near-shore in protected areas such as coves and harbors. Although they are generally found inshore, they do range to slightly deeper waters.

Feeding 

Mud Dog Whelks are scavengers that feed on dead fish and other organic material.