Tandonia (Tandonia) budapestensis (Hazay, 1881)
M. gagates, T. sowerbyi
External: Mantle <1/3 body length; forms a "C" when contracted; gray-brown body with somewhat darker dorsum on preserved specimens, with black spots all over and concentrated on top of dorsum and mantle; dark dorsum, to black or dark brown; gray-yellow or orange keel; dark horseshoe groove in mantle, groove along foot sole, and grooves in dorsum; mantle may be lighter than dorsum; gray edge of pneumostome; keel extends from tail tip to mantle; 3-part sole gray or orange-gray with a dark central section; thick, clear mucus that can form threads, orange to yellow transparent, becoming milky when perturbed (Quick 1960; Kerney & Cameron 1979; Wiktor 1996; Yildirim & Kebapçi 2004).
External: Internal shell 3 x 1.25 mm, brown; longish epiphallus and penis; club-shaped epiphallus about equal in length to penis; rounded penis; strong penial retractor muscle; oviduct tubular; vagina about width of oviduct and very short; wide, long spermatheca duct, and cylindrical spermatheca; two white, lobular accessory glands attached closely to vagina by multiple ducts; no atrial stimulator; long, thin spermatophore that is twisted, covered with spines, and ~16 mm long (Quick 1960; Kerney & Cameron 1979; Wiktor 1987, 1996).
Differs from - M. gagates and T. sowerbyi as body only partly contracts and forms a "C", no stimulator in atrium, longer spermathecal duct; 16 mm spermatophore thin and twisted (Quick 1960).
Eggs: 2.9 x 2.25 mm; yellow, leathery (Quick 1960).
Juveniles: 4.5 mm long, yellow-gray with keel at hatching (Quick 1960).
To 70 mm long extended; preserved: to 42 mm long, 5 mm wide, 11 mm long mantle (Wiktor 1987).
Ecology and Distribution
Native to: central Europe (Austria to Transylvania) (Yildirim & Kebapçi 2004); probably S Alps and N Balkans (Wiktor 1987)
Non-native to: Belgium, Czech Republic, Iceland, Poland, Turkey, UK (Yildirim & Kebapçi 2004), USA (introduced to Washington, DC and Philadelphia urban parks) (Reise et al. 2005).
For its defense, T. budapestensis is aposematically-colored (orange line along keel) and toxic to carabid beetle predators (Symondson 1997).
Occurs in shrubland, cultivated land, gardens, roadsides, wastelands, rocky habitats, and sometimes forest; synanthropic where introduced; to 1500 m in Bulgaria; takes shelter under rocks, leaf litter, and detritus (Quick 1960; Wiktor 1983; Yildirim & Kebapçi 2004).
T. budapestensis is a pest species (Kerney & Cameron 1979) that consumes roots (Chatfield, 1976).
- Limax gracilis Leydig, 1876 (synonym)
- Amalia budapestensis Hazay, 1881 (synonym)
- Amalia Cibiniensis Kimakowicz, 1884 (synonym)
- Milax gracilis valachicus Grossu et Lupu 1961 (synonym)