Milacidae Ellis, 1926
About 50 species are in the family Milacidae (Barker & Efford 2004). The center of diversity is in the Mediterranean region, especially in the former Yugoslavia and Greece (Wiktor 1996).
Mucus protects them from drying out when exposed. In drought, their thick mucous lines shelter cavities, and many individuals may share shelter (Wiktor 1987).
External: Black, brown, creamy colored body with no stripes, and often with dark pigment in the skin grooves; strong keel between mantle and tail tip; small mantle (<1/3 length of body) with granular surface pattern and horseshoe-shaped groove; 3-part sole with herring-bone pattern in the middle part; thick, transparent mucous that becomes thinner, opaque, and white or colored when perturbed (Wiktor 1983, 1987; Schileyko 2003).
Internal: Flat, oval, symmetrical internal shell; epiphallus and penis present; long vas deferens joins epiphallus apically; epiphallus divided from penis by a constriction (papilla inside), where a muscular retractor attaches; long, cylindrical oviduct; thick-walled spermatheca duct, attaching to vagina; accessory glands attaching to vagina or atrium; retentor muscles attach atrium to body wall; spermatophores yellow to red, with long filament, a wider sperm-containing part, and a covering of hooks; rectal coecum present (Wiktor 1983, 1987; Schileyko 2003).
Milacid species are distinguished through characteristics of the spermatheca and epiphallus (size, shape) and stimulator/sarcobelum (presence, shape) (Kerney & Cameron 1979).
Eggs: calcified, opaque, and white to pink to yellow; few to 20+ laid per clutch (Wiktor 1987).
.
Medium to large slugs, up to 100 mm long (Wiktor 1983).
Mostly occur on the Mediterranean and Black Sea coasts in S and W Europe, the Balkan Peninsula (SE Europe), Asia Minor, and N Africa, with some species in the British Isles and Central Europe (Schileyko 2003; Barker & Efford 2004).
Dry, Mediterranean habitat. Ground-dwelling. Most occupy rocky areas, some in leaf litter, a few in soil (Wiktor 1987).
Probably live >1 year, because adults and juveniles coexist, Mate in late summer to fall (Wiktor 1987).
Usually herbivorous on dead and live plants. Some species occasionally carnivorous.