Amynthas agrestis

Amynthas agrestis, the Asian jumping worm,^{[note 1]} is a species of worm in the family Megascolecidae.^[2] It has a smooth, glossy, grey or brown body with a milky-white clitellum,^[3] and can range from 1.5 to 8 in (3.8 to 20.3 cm) in length.^[3] Amynthas agrestis is native to Japan and the Korean Peninsula, and was introduced to North America due to increased human activity during the 19th century;^[4][5][6][7] it is considered to be an invasive species in the United States. Worms within the genus Amynthas (jumping worms) reproduce and develop quicker than their European counterparts.^[8]

Amynthas agrestis
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Annelida
Clade:	Pleistoannelida
Clade:	Sedentaria
Class:	Clitellata
Order:	Opisthopora
Family:	Megascolecidae
Genus:	Amynthas
Species:	A. agrestis
Binomial name
Amynthas agrestis (Goto & Hatai, 1899)

Ecology and Behavior

Amynthas agrestis became a problem in the United States, specifically the Southern United States, during the 19th century. Concern is increasing about this invasive species.^{[9][10][11][12]}

One of the main concerns is their overconsumption of leaf litter, which impacts the microbial and species diversity of the native soil. The removal of organic materials in top soil damages soil structure resulting in less water retaining ability, causing stunted growth for plants, and the lack of leaf litter makes plants less firmly rooted and more susceptible to being washed away by rain^[13]. The worm castings result in an appearance similar to coffee grounds.^[14][15].They do not burrow very deeply and mostly remain in the topsoil, and thus do not contribute much to soil aeration compared to other common earthworm species.^[15].

Many ecological scientists have created ways to control this invasive species. One of the main ways to control A. agrestis is controlled burn in grassy fields and some forests. This method removes leaf litter, the main food source for the species, which should thoroughly control its overall population.^[16]

The names Crazy and Jumping worm originate from the worm thrashing around rapidly when threatened, and it can also detach its tail to aid escape^[17]. ^[18].

Life cycle

The Asian jumping worm follows an annual life cycle. At least six months out of the year, it spends its time in the larval stage, then adults appear between May and June.^[5]

Notes

1. The species goes by many common names, including the rustic jumping worm, the Alabama jumper, and the Asian crazy worm.