Tropidoclonion is a genus of small colubrid snakes, commonly known as lined snakes, which are endemic to North America. The single species in the genus, Tropidoclonion lineatum, has four subspecies.
- Tropidoclonion lineatum annectens Ramsey, 1953 - central lined snake
- Tropidoclonion lineatum lineatum (Hallowell, 1856) - northern lined snake
- Tropidoclonion lineatum mertensi H.M. Smith, 1965 - Mertens' lined snake
- Tropidoclonion lineatum texanum Ramsey, 1953 - Texas lined snake
Lined snakes are found throughout the central United States from Illinois to Texas. They prefer grassland areas with soft, moist soils.
Lined snakes are olive green to brown with a distinctive tan or yellow stripe down the back from head to tail. They have similar stripes down each side on scale rows 2 and 3. On the belly, they have a double row of clean-cut black half-moon spots running down the middle. They have narrow heads and small eyes.
Adult size is typically less than 35Â cm (14 inches) in total length. However, maximum recorded total length is 53 cm (21 in).
The keeled dorsal scales are arranged in 19 rows at midbody. There are only 5 or 6 upper labials.
Lined snakes are semifossorial, spending most of their time hiding under rocks, leaf litter, logs, or buried in the soil. The majority of their diets consist of earthworms.
They are ovoviviparous, the young being born in August. The average brood is seven or eight. The newborn juveniles are 10-12 cm (4-4Â¾ in.) long at birth.
- Conant, R., and W. Bridges. 1939. What Snake Is That? A Field Guide to the Snakes of the United States East of the Rocky Mountains. D. Appleton-Century. New York and London. Frontispiece map + viii + 163 pp. + Plates A-C, 1-32. (Tropidoclonion lineatum, pp. 114-115 + Plate 21, Figure 63.)
- Hallowell, E. 1856. Notice of a Collection of Reptiles from Kansas and Nebraska, presented to the Academy of Natural Sciences, by Dr. Hammond, U. S. A. Proc. Acad. Nat. Sci. Philadelphia 8: 238-253. (Genus Microps, p. 240; and species Microps lineatus, p. 241.)
- Stebbins, R.C. 2003. A Field Guide to Western Reptiles and Amphibians, Third Edition. The Peterson Field Guide Series. Houghton Mifflin. Boston and New York. xiii + 533 pp. ISBN 0-395-98272-3 (paperback). (Tropidoclonion lineatum, p. 391 + Plate 50 + Map 168.)
- Wright, A.H., and A.A. Wright. 1957. Handbook of Snakes of the United States and Canada. Comstock. Ithaca and London. 1,105 pp. (in 2 volumes) (Genus Tropidoclonion p. 879 + Figure 20, a-c, on p. 71; and species Tropidoclonion lineatum, pp. 879-884, Figure 252., Map 62.)
- Zim, H.S., and H.M. Smith. 1956. Reptiles and Amphibians: A Guide to Familiar American Species: A Golden Nature Guide. Simon and Schuster. New York. 160 pp. ("Lined Snake", pp. 106, 156.)
- Species Tropidoclonion lineatum at The Reptile Database
- Tropidoclonion at Oklahoma Snakes