Leeches are annelids and there are fresh water, terrestrial, and marine leeches. Leeches are hermaphrodites and not all leeches feed on blood as commonly known.

Chainstrap Leech

This spotted leech scientifically named Phytobdella catenifera of Malaysia is a large terrestrial leech that can grow up to 5cm long. It was named after the striking chain-striped pattern on the creature's back. This leech is rarely seen because it is only attracted to reptiles and is of no threat to humans.

China Leech

Striped leech…well, this leech looks gorgeous for its unique stripe pattern. Being suck by a leech is considered by many people a horrible experience because this creature is so hard to remove from the flesh.

Horse Leech

This creature is slimy and sticky but…it is of importance to humans. This species is a Medicinal Leech. The most common medicinal leech is the Hirudo medicinalis, the European Medical Leech. Other medicinal leeches include Hirudo orientalis, Hirudo verbena, Hirudo troctina, Hirudinaria manilenesis or Asian Medical Leech and Macrobdella decora or North American Medical Leech.

Swallowing Leech （Erpobdella octoculata）

This leech has a very unusual name - "Swallowing Leech". We are all aware that leeches suck but this one doesn't really have jaws, it just swallows its prey whole. It grows about 5 or 6 cm in length and it feeds on midge larvae, worms and snails.

Sidney Leech

Sidney Leech is a true leech. True leeches （Euhirudinea） are an infraclass of the Hirudinea

True leeches are subdivided into two groups; the first group is called proboscisless leeches and the second group is called jawless leeches.

Giant Americobdella Leech

This brightly colored leech commonly called the Giant Americobdella Leech is from Chile. It preys on earthworms and swallows them in whole.

水蛭是环节动物，有淡水水蛭，陆地水蛭和海生水蛭。水蛭是雌雄同体的，但并不是所有水蛭都嗜血。

链带水蛭

科学上称作马来西亚Phytobdella catenifera的水蛭是一种可以长到5厘米长的大型陆地水蛭。是根据它背部明显的链带图案而命名。这种水蛭只被爬行动物吸引，对人类没有威胁，因此很少见。

瓷水蛭

斑纹水蛭，它独特的斑纹看起来很漂亮。对许多人们来说被这种水蛭吸食是种恐怖的经历，因为这种水蛭难以从血肉中移除。

马状水蛭

这种水蛭纤细又粘人，但对人类很重要。这是一种医学水蛭。最常见的医学水蛭是药用水蛭，欧洲的医学水蛭。其他的包括药用水蛭东方，药用水蛭马鞭草，药用水蛭Hirudo troctina,水蛭manilenesis或亚洲医用水蛭，以及Macrobdella decora或北美医用水蛭。

吞咽水蛭（Erpobdella octoculata）

这种水蛭有着不寻常的名字--吞咽水蛭。我们都发现水蛭吸血，但这种水蛭并没有爪子，它只会全部吞咽。它长度约为5或6厘米，以幼蚊虫，蠕虫，蜗牛为生。

悉尼水蛭

悉尼水蛭是真的水蛭。真的水蛭是水蛭的一种附纲。分为两类，第一类称作没有鼻子和嘴的水蛭，第二类叫做无爪水蛭。

巨型Americobdella水蛭

这种颜色亮丽的水蛭通常叫巨型Americobdella水蛭，来自智利。它捕获蚯蚓，而且全吞噬。