Desert Tortoises (Gopherus spp.) Fact Sheet: Physical Characteristics

Body measurements

Sources: Bonin et al. (2006) [length]

• Largest terrestrial turtle in the United States.
• High-domed shell allows large space for lungs and efficient thermoregulation.
• Front limbs shovel-like.
• Prominent growth lines on scutes (also called scales or shields)
• Carapace (top) brown or gray without a pattern, but often may be brown or orange in the center, especially in young.
• Plastron (underside) yellowish or brownish and is not hinged.
• Like most turtles, on the shell have 5 vertebral scutes, 4 pairs of costal (rib) scutes, 22 scutes around the margins and a single nuchal scute.
• Like all turtles, good hearing, but no external ear; no teeth (have beak)

• Adults sexually dimorphic with males larger than females
• Males have concave plastron (bottom shell), longer tail, and enlarged glands under chin
  • Glands possibly exude protein-like substance during breeding season
• Female's plastron is flat, slightly expanded towards rear

• Limbs stocky, elephantine
  • Forelimbs somewhat flattened, hindlimbs columnar
  • The turtles in this family (Testudinidae) have no connecting web of skin between digits
• Large cone-shaped scales on limbs
• Light eye ring
• Iris of eye usually greenish yellow
• Head relatively narrow; ridges on upper jaw meeting at a sharp angle
• Forelimbs cover opening when drawn in
• Forelimbs have five digits; hindlimbs, four
  • Claws on front limbs for digging burrows
  • Females use claws for digging nest
  • A spur present on the hind limb.
• Gular area (part of plastron lying beneath the extended head) slightly forked (Bonin et al 2006)
• A single scute underneath the armpits (axillary scute). (Ernst & Lovich 2009)

A desert tortoise's coloration helps camoflauge it among rocks and sand.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Auffenberg (1974)
Bonin et al. (2006)
Ernst & Lovich (2009)
Stebbins (2003)