''Amynthas'' is a genus of

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

s in the family

Megascolecidae The Megascolecidae is a taxonomic family of earthworms which is native to Madagascar, Australia, New Zealand and both South East Asia and North America. All species of Megascolecidae belong to the Clitellata class. Megascolecidae are a large fami ...

. 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 The clitellum is a thickened glandular and non-segmented section of the body wall near the head in earthworms and leeches, that secretes a viscid sac in which eggs are stored. It is located near the anterior end of the body, between the fourteent ...

, which is pale, annular, is close to the head, and lies flat against the body.''Wisconsin DNR Forest Health.''
Jumping Worms (''Amynthas spp.'') Fact Sheet
. Updated April 2015. Accessed Dec 22 2022. They vary in size between .

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 rapped in small cocoons, which overwinter while the adults die off. The young then emerge next spring.

Species

* ''

Amynthas agrestis ''Amynthas agrestis'', the Asian jumping worm,The species goes by many common names, including the rustic jumping worm, the Alabama jumper, and the Asian crazy worm. is a species of worm in the family Megascolecidae. They have a smooth, glossy g ...

'' (Goto and Hatai, 1899) * ''Amynthas alexandri'' (Beddard, 1900) * ''Amynthas assimilis'' (Hong & Kim, 2002) * ''Amynthas borealis'' (Panha & Bantaowong, 2011) * ''Amynthas comptus'' (Gates, 1932) * ''Amynthas defecta'' (Gates, 1930) * ''Amynthas dorualis'' * ''Amynthas exiguus'' (Gates, 1930) * ''Amynthas fucosus'' (Gates, 1933) * ''Amynthas gracilis'' (Kinberg, 1867) * ''Amynthas hilgendorfi'' (Michaelsen, 1892) * ''Amynthas hupbonensis'' (Stephenson, 1931) * '' Amynthas japonicus'' (Horst, 1883) * ''Amynthas kinmenensis'' * ''Amynthas longicauliculatus'' (Gates, 1931) * ''Amynthas luridus'' (Shen, Chang, & Chih, 2019) * ''

Amynthas mekongianus ''Amynthas mekongianus'', the Mekong worm or Mekong giant earthworm, previously known as ''Megascolex mekongianus'', is a species of earthworm in the family Megascolecidae. It is native to the vicinity of the River Mekong in southeastern Asia an ...

'' (Cognetti, 1922) * ''Amynthas minimus'' * ''Amynthas mirifius'' * ''Amynthas moakensis'' * ''Amynthas morrisi'' (Beddard, 1892) * ''Amynthas mujuensis'' * ''Amynthas obsoletus'' * ''Amynthas papulosus'' (Rosa, 1896) * ''Amynthas phatubensis'' (Panha & Bantaowong, 2011) * ''Amynthas polyglandularis'' * ''Amynthas pulvinus'' * ''Amynthas ruiyenensis'' (Shen, Chang, & Chih, 2019) * ''Amynthas sangumburi'' * ''Amynthas siam'' (Blakemore, 2011) * ''Amynthas srinan'' (Panha & Bantaowong, 2011) * ''Amynthas taiwumontis'' * ''Amynthas tessellatus'' * '' Amynthas tokioensis'' (Beddard, 1892) * ''Amynthas tontong'' (Panha & Bantaowong, 2011) * ''Amynthas wuhumontis'' * ''Amynthas wujhouensis''

References

{{Taxonbar, from=Q4749574 Haplotaxida Annelid genera Megascolecidae