Blanding’s Turtle

Emydoidea blandingii (Holbrook, 1838)

Blanding's Turtle
Blanding’s Turtle, Will Co., IL. photo by C.A. Phillips
Blanding's Turtle
Blanding’s Turtle, Will Co., IL. photo by C.A. Phillips

Key Characters: Bright yellow chin and throat; notched upper jaw; hinged plastron.

Similar species: Box turtles, Spotted Turtle. See Key to Adult Turtles of Illinois for help with identification.

Subspecies: None recognized.

Blanding's Turtle
Blanding’s Turtle, Lee Co., IL. photo by A.R. Kuhns

Description: Medium-sized (up to 24 cm CL) turtle with dark shell. Head and carapace profusely decked with light spots and dashes. Each plastral scute patterned with a large dark blotch usually bordered with yellow but, in older individuals, entire plastron may be black. Pleural scutes of young unpatterned or have faint radiating streaks. Disproportionately longer tail than box turtles. Male with concave plastron, heavier tail with cloacal opening behind edge of carapace, and dark markings on upper mandible.

Habitat: Quiet waters in marshes, prairie wetlands, wet sedge meadows, and shallow, vegetated portions of lakes.

Natural History: Usually found in and around water, but moves long distances overland. Long-lived, up to 77 years. Chiefly carnivorous, eating snails, insects, crayfish, and vertebrates. Female nests in late May and June, laying one clutch of about 12 hard-shelled, ellipsoidal eggs (ca. 30 x 20 mm).

Status: State endangered. Major threat has been habitat destruction. Relatively common in appropriate habitat from Illinois River northward. Rare farther south.

Etymology: Emydoidea – emydo (Greek) for ‘freshwater tortoise’; eidos (Greek) for form, resemblance; blandingii – (New Latin) in honor of Dr. William Blanding (1772-1857)

Original Description: Holbrook, J.E. 1838. North American Herpetology. Ed. 1. Vol. 3. J. Dobson and Son, Philadelphia. 3:122 pp.

Type Specimen: Holotype, ANSP 26123

Type Locality: “Fox river, a tributary of the Illinois”

Original Name: Cistuda blandingii Holbrook, 1838

Nomenclatural History: The names Testudo flava Lacepede, 1788 and Testudo meleagris Shaw, 1793 were suppressed by the ICZN based on petition by Mertens & Wermuth (1961), but Loveridge & Williams (1957) held the contrary opinion that those names should be referred to the synonomy of the European species Emys orbicularis. The Blanding’s Turtle has been referred to as Cistudo blandingii and Emys blandingii in the Illinois literature.