Deroceras Rafinesque, 1820
Deciduous and mixed forest; usually in undergrowth and under stones, sometimes under logs and bark (Wiktor 1983).
Deciduous and mixed forest; usually in undergrowth and under stones, sometimes under logs and bark (Wiktor 1983).
Three species are known in the genus Krynickillus (Wiktor 2000).
Deroceras may defend themselves by tail-wagging and slapping and by quickly fleeing (Rollo & Wellington 1979).
External: Small to medium slugs; spindle-shaped, thin body; body usually gray-cream but ranging from white to black, and either plain or spotted; mantle ~1/3 body length; pneumostome post-medial on mantle; slight keel on posterior; clear mucus that for some species, may become milky white when the animal is perturbed (Kerney & Cameron 1979; Wiktor 2000; Schileyko 2003).
Internal: Rectal caecum usually present; short, globular penis; penial gland and often flagella and appendix present; penial retractor muscle usually joined to penis apex; conical or flat stimulator (sarcobelum) in penis (Kerney & Cameron 1979; Wiktor 2000; Schileyko 2003).
Penis shape and flagellum are distinguishing characters among species (Kerney & Cameron 1979).
Preserved: 40-45 mm long (Wiktor 1983).
Black Sea area: Romania, Bulgaria, Turkey, Crimea, Caucasus (Wiktor 1983).
Forest and open fields; usually moist habitat (Wiktor 2000). .
Deroceras generally feeds on live plants (Kerney & Cameron 1979).
Many species of Deroceras are serious agricultural pests.
Body size up to 45 mm (after preservation slugs become smaller, about 25 mm then); robust, mantle large (sometimes 1/2 of body length). .
Holarctic N of Sahara, Arabia, India, S China and Central America, except N margins of Siberia and N America, isolated in Ethiopia. The most numerous species are known from the Balkans, Asia Minor and the Caucasus.
Life cycle short, often several generations are present at the same time. Life cycles in species living in colder regions 6-14 months, in the south down to 2 months.