Graham’s Crayfish Snake

Regina grahamii (Baird & Girard, 1853)

Graham's crayfish snake
Graham’s crayfish snake, Lake Co., IL photo by C.A. Phillips
graham's crayfish snake
Graham’s crayfish snake, Lake Co., IL photo by C.A. Phillips

Key Characters: Yellow stripe on scale rows 1-3; back scales strongly keeled; anal plate divided.

Similar Species: Queensnake. See the Key to Snakes of Illinois for help with identification.

Subspecies: None currently recognized.

Description: Medium-sized (up to 100 cm TL), relatively stout-bodied brown or dark olive water snake. Side stripe bordered below by a narrow, irregular black stripe along the outer edges of belly scales. Sometimes a midback light stripe is present. Belly plain yellow or off-white, the hind third with a faint dark line or row of dots down the center. Stripes and belly more yellow and midback light stripe more frequent in juveniles.

Habitat: The still-water, prairie equivalent of the queen snake, it lives in and along banks of soft-bottomed, heavily vegetated lakes, ponds, sluggish streams, sloughs, and roadside ditches.

Natural History: Secretive and difficult to catch, it basks on rock piles and overhanging branches. Hibernates in crayfish burrows and burrows it excavates. Mates in late April or May and gives birth to 10-20 young in late July, August, or September. Newborn 15-25 cm TL. Frequent prey are recently molted crayfish, but fish and frogs also are eaten. Predators include other snakes, large shore birds, and mammals.

Status: Widespread but uncommon. Absent from the Wabash and Ohio river counties.

Etymology: Regina – regius (Latin) meaning queen; grahamii – (Latin) meaning seven; grahamii (New Latin) in honor of James D. Graham (1799-1865).

Original Description: Baird S.F. & C. Girard. 1853. Catalogue of North American reptiles in the Museum of the Smithsonian Institution. Part I. Serpents. Smithsonian Misc, Coll. 2(5):172 pp.

Type Specimen: Holotype not designated, but syntypes were at ANSP but are now missing.

Type Locality: “Rio Salado” [Bell County, Texas]

Original Name: Regina grahamii Baird & Girard, 1853.

Nomenclatural History: Davis and Rice (1883) used Tropidonotus grahamii to refer to this species. Smith (1961) used the combination Natrix grahamii.