Common name: Tramp slug
Scientific name: Deroceras invadens
Remarks: Deroceras invadens was described as a new species in 2011 (Reise et al 2011). Prior to this discovery the species was thought to be Deroceras panormitanum
Counties in California where collected: 5 counties: Alameda, Contra Costa, Los Angeles, San Francisco, Santa Clara (Roth and Sadeghian, 2006).
Ecology: Synanthropic (usually associated with people) species, common in gardens, parks, greenhouses, pastures, roadsides, arable land and disturbed forest. Deroceras invadens feeds on both living and dead plants and is a serious pest of horticulture, pasture, gardens and crop systems including asparagus and lettuce (Barker, 1999).
Description: Small, slim slugs up to 30mm (1.2") in length. Mantle (fleshy saddle shaped structure behind the head) is approximately one-third length of the body. Mucus colorless (Barker, 1999). In California the body is usually brown but can also be gray. Sole usually light gray. Body wall appears to be thin which gives specimens a translucent appearance (Forsyth, 2004). In profile, the tip of the tail rises up from the sole vertically and may curve backwards (de Winter, 1988).