长吻海蛇Hydrophis platurus
别名：黑背海蛇、黄腹海蛇
形态特征：头狭长，吻长。体极侧扁。体最大直径不到颈径的2倍。体全长550～700mm。头背黑色，唇缘黄色，身体背黑腹黄截然分开，相隔处或有淡黄纵纹。尾部有5～10块黑斑，或黑斑彼此相连呈波状纹，或不规则，尾端黑色。上唇鳞8～9枚，偶有7枚、10枚、11枚，大多入眶，一般呈3-1-4式，第二枚上唇鳞与前额鳞相切，不入眶者，其间隔以眼下鳞。背鳞（40～51）-（43～59）-（34～52）行，呈六角形或方形，镶嵌排列，背部平滑，体侧具短棱，最下几行体鳞具2～3个小短棱，成年雄性较强，腹鳞不易区别，尾下鳞41～66对。
生活习性：生活于海洋，能远离海岸，是分布最广的海蛇。以各种小型鱼类为食，偶食甲壳类动物。
地理分布：国内分布于自胶东湾以南的东部沿海地区及附近海域；国外广布于太平洋及其海岛沿岸。东达中美西海域、西达非洲东南部、北到日本海、南到澳大利亚东北沿海。
环渤海地区分布：山东沿海。
生存现状：无危（LC）
Squamata Elapidae Hydrophis
65.Hydrophis platurus
Description Adults up to 550-700mm TOL, head is narrow and long; long snouts.Body is very flat; neck size is 2 times wider than the body.Head dorsum is black; lips edge are yellow; black dorsum; ventral is yellow with light yellow vertical stripes; 5-10 black spots on the tail, connecting to each other and in ripple or irregular shape; tail end is black; 8-9 supralabials and sometimes 7, 10 or 11; scales are in the eye orbits shaping in 3-1-4;tangent scales on the supralabials and forehead; some scales, not in the eye orbits, separated by the scales under the eyes.Dorsal scales are arranged in (40～51) -(43～59)-(34～52) rows and in hexagon or square shape; dorsum is smooth with short tubercles on body sides; the last rows of scales have 2-3 short tubercles; adult males' scales are strong; ventral scales are hard to distinguish; 41-66 subcaudals.
Behaviour Hydrophis platurus live in the sea and could live far away from the coasts.They are the most widely distributed sea snake.They feed on all kinds of small fish and shellfish.
Distribution Known in the south of Jiaodong Bay in the East China; also islands across the Pacific, east to the western sea of Central America, west to the southeast of Africa,north to the Japan Sea and south to the coasts of northeast Australia at abroad.Distribution around Bohai Sea: in the coasts of Shandong Province.
Conservation Least concern (LC).