Tropidoclonion
Tropidoclonion is a genus of snake in the subfamily Natricinae of the family Colubridae. The genus is monotypic, containing the sole species Tropidoclonion lineatum, commonly known as the lined snake. The species is native to the central United States.
Common names
Additional common names for Tropidoclonion lineatum include common snake, dwarf garter snake, grass snake, line snake, ribbon snake, streaked snake, striped snake, and swamp snake.Subspecies
Four subspecies are recognized as being valid, including the nominotypical subspecies.- Tropidoclonion lineatum annectens – central lined snake
- Tropidoclonion lineatum lineatum – northern lined snake
- Tropidoclonion lineatum mertensi – Mertens' lined snake
- Tropidoclonion lineatum texanum – Texas lined snake
Etymology
The subspecific name, mertensi, is in honor of German herpetologist Robert Mertens.Geographic distribution
The lined snake is found throughout the central United States from Illinois to Colorado to Texas.Habitat
The preferred natural habitats of Tropidoclonion lineatum are savanna, shrubland, and grassland areas with soft, moist soils, but it is also found in disturbed and artificial habitats such as city backyards, vacant lots, and trash dumps.Description
The lined snake is olive green to brown with a distinctive tan or yellow stripe running down the middle of the back from head to tail. It has similar stripes, one down each side on scale rows 2 and 3. On the belly, it has a double row of clean-cut black half-moon spots running down the middle. It has a narrow head and small eyes.Adult size is typically less than 35 cm in total length. However, maximum recorded total length is 53 cm.
The keeled dorsal scales are arranged in 19 rows at midbody. There are only 5 or 6 upper labials.