The leech sucks the host's skin tightly with the front sucker, and then cuts a Y-shaped wound from the maxillary teeth to suck blood.

The following is the introduction of leeches:

Leech, commonly known as leech, is recorded in Shennong Herbal Classic and has high medicinal value. It grows and breeds in inland freshwater areas and is a traditional special medicinal aquatic animal in China. Its dried product can be used as traditional Chinese medicine after soaking, and has the effects of treating apoplexy, hypertension, blood stasis, amenorrhea and traumatic injury.

In recent years, leech preparation has been found to have special effects in preventing and treating cardiovascular and cerebrovascular diseases and anticancer. Historically, it was mainly natural fishing. Due to the abuse of pesticides and fertilizers and the environmental pollution caused by industrial and agricultural "three wastes" in recent years, the wild natural resources have decreased sharply. With the further development of medicinal value of leech, its market demand potential is huge.

Leech, also known as medical leech, commonly known as leech, is distributed all over the world, with more than 300 species, and there are more than 100 species in China. ? All the dried animals of golden leech, brown leech and Japanese leech have been recognized as Chinese herbal medicines by People's Republic of China (PRC) Pharmacopoeia (China Pharmacopoeia for short).

Refer to Baidu Encyclopedia-Leech for the above information.