Fauna
Reptile

Tamaulipan Rock Rattlesnake

Crotalus morulus

Also known as Tamaulipan Mottled Rattlesnake, Eastern Rock Rattlesnake

Tamaulipan rock rattlesnakes inhabit the damp, high-elevation pine-oak forests and limestone outcrops of northeastern Mexico Sierra Madre Oriental. Their dark, mulberry-like mottled bands provide exceptional camouflage against mossy rocks and leaf litter while they wait in ambush for unsuspecting lizards and small rodents. Though timid and quick to retreat into deep rock crevices, these small pit vipers rely on heat-sensing facial pits to hunt effectively in cool montane environments.

VenomousMontaneReptile
Tamaulipan Rock Rattlesnake reference
William L. Farr / CC BY-SA 4.0 · cc-by-sa
—observations
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Near ThreatenedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNear ThreatenedRed List categories, explained →
Key facts
Diet & preyLizards, Mice, Frogs
Predators
  • Eagles
  • Hawks
  • Larger snakes
ThreatsHabitat loss, climate warming, illegal collection for the pet trade
HabitatsHigh-elevation pine-oak forests, limestone scree, cloud forests
Life span15–20 years
Classification
  1. FamilyViperidae
  2. SpeciesCrotalus morulus
Range & activity
Range data is not available yet.
Safe observation
Interaction riskVery high
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is very high
Venomous bite can cause severe local tissue damage; maintain a safe distance of several meters.
Why it is dangerous
Possesses cytotoxic and hemotoxic venom that breaks down blood tissues, requiring urgent antivenom treatment.
How to recognize a risky encounter
Recognized by slate-grey body with dark, mottled mulberry-like crossbands and a small rattle on the tail tip.
What to do
Never corner, handle, or step over rocks without checking first; back away slowly if encountered.
What to notice
Small, rock-dwelling rattlesnake unique to cloud forests and limestone habitats of the Sierra Madre Oriental.
Support conservation
Avoid publishing precise location data online to protect wild populations from commercial collection.
Responsible observation
  • Watch your footing: Scan carefully around limestone outcrops and rock slides where these snakes bask or conceal themselves.
  • Listen for warnings: Give a wide berth if you hear a dry, buzzing rattle, as these secretive snakes blend seamlessly into rocks.
  • Use a flashlight: Exercise caution during evening hikes when temperatures drop and snakes move across exposed trails.
Related species
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