鼠标蛇（学名：Ptyas mucosus）又称华鼠蛇、水南蛇、水律蛇、菜蛇、南蛇、华锦蛇，是游蛇科鼠蛇属的一种无毒蛇。

鼠标蛇长达2米多；背面黄褐色，后部有不规则黑色的横斑；头部为黑褐色，黑色唇鳞缝；黄白色腹面，腹鳞后缘两侧为黑色。

Ptyas mucosa, commonly known as the oriental ratsnake, Indian rat snake, or dhaman, is a common species of colubrid snake found in parts of South and Southeast Asia. Dhamans are large snakes, growing to 2 m (6.6 ft) and occasionally even to 3 m (9.8 ft). Their colour varies from pale browns in dry regions to nearly black in moist forest areas. Dhamans are diurnal, semi-arboreal, non-venomous, and fast-moving. Dhamans eat a variety of prey and are frequently found in urban areas where rodents thrive. The species is also known as ගැරඩියා (geradiya) in Sinhala (Sri Lanka) and ngu sing hang lai in Thai (Thailand), in Kannada language ಜೇರೋತನ(Jerothana), Jerri pothu or Joru pothu or Jerri Goddu( in.Telugu language), Sara paambu( in Tamil language) and Bairokh(বাইৰখ) in Assamese language.