黑头剑蛇Sibynophis chinensis
地方名：黑头蛇
形态特征：体形细长的小型无毒蛇，成体全长600～800mm 。头背灰黑色（偶见棕色），上唇鳞白色，头颈部有一块黑斑，黑斑后缘有一条细白横纹，颈部后段常有一段黑色细纵纹。体背棕褐色，腹部白色，具腹链纹。上唇鳞多为9枚，呈3-3-3式，下唇鳞多为8枚，第4枚最长，第5枚最大。背鳞17-17-17行，平滑无棱。腹鳞171～187枚，尾下鳞58～122对，肛鳞完整。
生活习性：常栖息于潮湿的山林，丘陵等地区。以蜥蜴为主食，偶食蛙类。
地理分布：在我国分布广泛，除黑龙江、吉林、辽宁、山东、内蒙古、宁夏、青海、新疆、西藏未见分布外，其余各省区均有分布。
环渤海地区分布：北京、天津、河北。
生存现状：无危（LC）。
注： 黑头剑蛇云贵高原亚种S.chinensis grahami腹鳞在185枚以上，尾下鳞110对以下。分布于贵州（威宁）、云南（昆明与曲靖间，武定）。黑头剑蛇米易亚种S.chinensis miyiensis腹鳞185枚以上，尾下鳞108对以上，分布于四川西南、云南东北。
Squamata Colubridae Sibynophis
60.Sibynophis chinensis
Description Adults up to 600-800mm TOL, body is slender and non-toxic.Head dorsum is greyish black (occasionally brown); supralabials is white; a black spot with a fine and white lateral stripe on the rear rim on the head and neck; a part of fine and black vertical stripe on the neck end; the body dorsum is brown, the ventral is white with chin stripes;9 supralabials are arranged in 3-3-3 rows and mostly 8 infralabials, the fourth one is the longest, the fifth one is the biggest.Dorsal scales are smooth and arranged in 17-17-17 rows, without tubercles; 171-187 ventral scales; 58-122 pairs of subcaudals; anal plate is complete.
Behaviour Sibynophis chinensis often live in the wet forests, mountains and hills.They maily feed on lizards, occasionally on frogs.
Distribution China: widely in China, except in Heilongjiang, Jilin, Liaoning, Shandong,Inner Mongolia, Ningxia, Qinghai, Xinjiang and Tibet.Distribution around Bohai Sea: in Beijing, Tianjin, and Hebei Province.
Conservation Least Concern (LC)
Notes Sibynophis chinensis grahami have more than 185 ventral scales, less than 110 subcaudals.They are found in Guizhou Province (Weining), Yunnan Province (the border between Kunming and Qujing, Wuding).S.chinensis miyiensis have more than 185 ventral scales, less than 108 subcaudals, they are found in the southwest of Sichuan Province and northeast of Yunnan Province.
