Meghimatium bilineatum (Benson 1842)
M. bilineatum is genetically undifferentiated throughout its range and therefore suspected to be a recent invader in most habitats. The species is a lineage within Meghimatium pictum (Tsai et al. 2011).
External: Extremely variable coloration; creamy to brown background color, with two dark lines on sides and one along dorsal midline, sometimes with spots in between; very variable coloration, with medial dark line absent and lateral slights spotty/faint in many populations; pale sole (Collinge 1899; Wiktor et al. 2000).
Internal: Jaw formed from 22-28 plates; long, thin vas deferens; penis long and folded in half or in thirds, 2x length atrium; penis with glandular papillae in apex and mid-section, and basal ¼ with internal ribs; retractor muscle attached to penis apex; ligula protruding from penis base into atrium; no or very short vagina; ovate spermatheca with a short, thin duct; atrium large and oval (Ikeda 1937; Wiktor et al. 2000; Tsai et al. 2011).
Eggs: White, stringed together with mucus; three or more batches laid per individual per spring, with an average of 932(!) eggs total for lab-reared slugs (Ikeda 1937).
Different lengths cited: 40-60 mm long (Azuma 1982; Tsai et al. 2011); to 90 mm long (Sysoev & Schileyko 2009); to 50 mm long preserved (Wiktor et al. 2000).
Probably everywhere the genus occurs; SE China: middle and lower Yangtse basin (Wiktor et al. 2000); found in China, Hong Kong, Taiwan, Japan, Hawaii (Tsai et al. 2011); Java (Van Benthem Jutting 1952); Far E Russia (Primorsky Territory, central Amur River Basin) (Likharev & Schileyko, MS; Sysoev & Schileyko 2009).
Invasive in Hawaii (Collinge 1899).
Occupies "humid moss under shrubs, occasionally on bare rocks after showers" (Wiktor et al. 2000); cultivated land (Tsai et al. 2011); urban areas such as gardens, parks, cemeteries; on smooth-barked live trees and rocks, and under dead logs (pers. obs.); found at about 1500-2500 m in Java (Van Benthem Jutting 1952).
May live up to 4 years in the lab, but usually dies in the spring after egg-laying in the field.
Ikeda (1937) found M. bilineatum to hatch in spring and fall, lay eggs in spring, become mature in the fall, and lay eggs the following spring. Can self-fertilize (Ikeda 1937).
Feeds on algae (pers. obs.); eats cucumber and carrots in the lab (Ikeda 1937).
Damaged commercial orchids in Taiwan (Liu et al. 1997).
Probably spread through agricultural activity (Tsai et al. 2011).