Amynthas is a genus of earthworms in the family Megascolecidae. They are known as jumping worms, snake worms, or crazy worms because of their erratic thrashing behaviour when disturbed. The genus is native to East Asia, but they are invasive in many areas of the United States. They are a matter of concern in many states, as they disrupt the native forest ecology by affecting soil structure and chemistry.
Appearance
Amynthas species can be differentiated from other earthworms by their clitellum, which is pale, annular, is close to the head, and lies flat against the body. They vary in size between 3.8 and 20.3cm (1.5 and 8.0in).
Life cycle
Amynthas species' faster reproduction rate and their ability to reproduce asexually (parthenogenesis) has contributed to their spread into the United States. The worms reach maturity in 60 days, which allows them to have two hatches per year. Eggs are wrapped in small cocoons, which overwinter while the adults die off at the first freeze each year. The young then emerge the next spring.
123Shen, H.-P.; Chang, C.-H. & Chih, W.-J. (2019). "Two new earthworm species of the genus Amynthas (Oligochaeta: Megascolecidae) from central Taiwan, with comments on some recent species assignments in Amynthas and Metaphire". Zootaxa. 4658 (1): 101–123. doi:10.11646/zootaxa.4658.1.4. PMID31716758.
