Tailored toxins: Coagulotoxic variations in Atropoides, Cerrophidion, Metlapilcoatlus, and Porthidium viperid venoms against diverse vertebrate plasmas.

Venom is an adaptative trait that allows predators to subjugate prey. Despite this, there remains a distinct lack of research regarding the coagulotoxic effects of snake venom upon a species preferred prey. Using thrombelastography, this study aimed to characterize coagulotoxic venom effects from the Central American pit viper clade of Atropoides, Cerrophidion, Metlpailcoatlus, and Porthidium against the plasma of model species: amphibian, avian, lizard and rodent. Venom from Atropoides and Metlapilcoaltus exhibited anticoagulant activity in rodent and lizard plasma by disrupting the formation of stable clots. While clotting time was reduced, the clots formed were weak and transient, indicating impaired coagulation. This activity did not correspond to avian and amphibian plasma, where no activity was observed. Porthidium volcanicum, Cerrophidion tzotilorum and Porthidium porrasi showed coagulotoxic activity against all plasmas tested. Consistent with the described procoagulant effect on human plasma, Porthidium volcanicum reduced clotting time and produced strong, stable clots in amphibian, lizard and rodent plasma. Intriguingly, this venom displayed an anticoagulant effect upon avian plasma, with clotting time significantly delayed. Cerrophidion tzotzilorum and Porthidium porrasi venoms produced an anticoagulant effect on avian plasma but had no effect against amphibian plasma. In addition, C. tzotzilorum and P. porrasi venoms displayed the fibrinogen-depleting pseudo-procoagulant/thrombin-like type of anticoagulant activity previously observed in human plasma against lizard plasma. However, they differed in their effects on rodent plasma. While C. tzotzilorum retained the pseudo-procoagulant/thrombin-like activity, P. porrasi delayed clotting time. The wide variation in activity observed within this study highlights the importance of studying venom activity upon relevant prey models and the limitations of extrapolating animal models to predict human related envenoming.