Lined Snake

Tropidoclonion lineatum (Hallowell, 1856)

Lined snake
Lined snake, photo by C.A. Phillips

Key Characteristics: White to gray midback stripe and another on each side; double row of dark half-moons extends down the midbelly; back scales keeled; anal plate not divided.

Similar Species: Common Gartersnake, Plains Gartersnake. See the Key to Snakes of Illinois for help with identification.

Subspecies: None currently recognized.

Description: Small (up to 35 cm TL), slender olive brown to gray-brown snake. Each pale stripe is bordered by a row of minute black dots (dots more conspicuous in young). Head small, barely wider than body.

Habitat: Grasslands and urban lots in former prairie, where it is found under rocks, logs, leaves, boards, and other debris.

Natural History: Active March to November, spending less time at the surface during hot summers and more after heavy rains. Mates in late August and 5-10 young are born the following August or September. Newborn are 7–12 cm TL. This secretive and semifossorial nocturnal snake subsists almost entirely on earthworms. Predators include other snakes, birds, and mammals. Often curls its tail into a tight coil when disturbed, but otherwise passive.

Status: Rare and known from only a few scattered localities, mostly urban vacant lots, in central counties.

Etymology: Tropidoclonion – tropis (Greek) meaning keel; klon (Greek) meaning twig ; lineatum – lineatus (Latin) meaning ‘of a line’

Original Description: Hallowell, E. 1856. Notice of a collection of reptiles from Kansas and Nebraska, presented to the Academy by Dr. Hammond, U.S.A. Proceedings of the Academy of Natural Sciences Philadelphia. 8. 238-253.

Type Specimen: Holotype. ANSP 5922

Type Locality: “Kansas”

Original Name: Microps lineatus Hallowell, 1856

Nomenclatural History: Garman (1890) used the spelling Tropidoclonium lineata.