South American Rattlesnake

The best-known rattlesnake in South America.

GenusCrotalus

RegionSouth AmericaSouth America

Photo: Salomão Janderson Ferreira Bispo · Source: iNaturalist · License: CC BY 4.0

Photo: Salomão Janderson Ferreira Bispo · Source: iNaturalist · License: CC BY 4.0

South American Rattlesnake

Danger Score

Final Danger Score

Venom Core

Lethality weighted 55% (potency × yield). Clinical weighted 45% (real-world CFR).

0.55 × 70 + 0.45 × 10083.5

Modifiers

Multiplicative scalers - amplify or reduce existing danger, can't create it from nothing.

× Speed (1.01)84.3

× Delivery (1.00)84.3

× Encounter (0.89)75.1

Speed = antivenom window. Delivery = fang efficiency. Encounter = exposure × temperament.

Score75

Type

NeurotoxicAffects the nervous system; disrupts nerve-muscle communication and can cause paralysis or respiratory failure.

Venom Yield

Moderate

Venom Speed

Quick

Delivery Method

Hinged front fangs

Potency (SC Equivalent)

0.340mg/kg LD50

Max Dry Yield

63mg dry

Fatality (Untreated)

50-75%

WHO Importance

Cat. 1

Local Effects

Pain at bite site

Neurological

Paralysis

Gastrointestinal

Nausea or vomiting

Causes of Death

Respiratory failure