Bornean Keeled Green Pit Viper
Extreme close up of a Bornean Keeled Green Pit Viper, Tropidolaemus subannulatus (Viperidae), showing its heat-sensing pits (the two whitish pits aside each eye).
These heat-sensing pits are a infrared-detecting system that allows vipers to detect prey in total darkness without reliance on sight, olfaction or hearing, but perceiving infrared radiation.
In humans bites by these snakes are often minor, but may cause moderate to severe local effects, with shock, but generally not necrosis or coagulopathy (clotting problems).
Antivenom is the key treatment for the envenoming, and multiple doses may be required. However, in the absence of specific antivenom, treatment is generally supportive and symptomatic.
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Photo credit: ©kkchome | Locality: Sarawak, Borneo, Malaysia