Dendrelaphis nigroserratus (common name: sawtooth-necked bronzeback) is a species of snake belonging to the bronzebacks (Dendrelaphis). It is found only in western and southwestern Thailand and the adjacent southeastern Myanmar. A specimen has been preserved in the British Natural History Museum, London since the early 20th century. Due to its resemblance to Wall's Bronzeback, the scientific name was formerly assigned under Dendrelaphis cyanochloris, the species name for Wall's bronzeback. It was formally described as a distinct species in 2012 by Gernot Vogel, Johan Van Rooijen and Sjon Hauser. According to the World Wide Fund for Nature report, it became one of the 367 important new species discovered in the Greater Mekong during 2012 and 2013.