Ovophis tonkinensis envenoming presenting with severe isolated thrombocytopenia and local necrosis: A case report

  Image Credit: iNaturalist (c) randall_f –  some rights reserved (CC BY-NC) Ovophis tonkinensis envenoming presenting with severe isolated thrombocytopenia and local necrosis: A case report Abstract Pit viper envenoming commonly causes venom-induced consumption coagulopathy with hypofibrinogenaemia. However, isolated thrombocytopenia without fibrinogen depletion is less recognised and may alter transfusion strategy. We report a confirmed  Ovophis tonkinensis  bite from northern Vietnam presenting with severe isolated thrombocytopenia and local necrosis. The case highlights the importance of serial platelet monitoring, awareness of fibrinogen availability and appropriate timing of antivenom and platelet support in resource-limited tropical settings. Duc ND, Hong Anh LN, Hong Khanh LN, Bach ND. Ovophis tonkinensis envenoming presenting with severe isolated thrombocytopenia and local necrosis: A case report. Tropical Doctor . 2026;0(0). doi: 10.1177/00494755261435153

Oscillating in darkness: Circadian rhythms of cave-dwelling scorpions

 

Oscillating in darkness: Circadian rhythms of cave-dwelling scorpions

ABSTRACT

Circadian rhythms, typically synchronized with light–dark cycles, regulate key biological processes in surface organisms. In caves, however, the absence of light may disrupt these rhythms or promote alternative temporal patterns. We examined locomotor activity in two cave-dwelling scorpions with contrasting degrees of subterranean adaptation: Troglorhopalurus translucidus (troglobitic) and Troglorhopalurus lacrau (troglophilic). Activity was monitored under constant darkness (DD), light–dark (LD), and constant light (LL). Both species retained circadian rhythmicity, but with distinct responses: T. translucidus and T. lacrau exhibited diurnal activity under LD and changes in period under DD and LL. These findings demonstrate that circadian regulation persists in cave-adapted scorpions, but its expression is shaped by evolutionary pressures, highlighting the plasticity of biological clocks in light-deprived environments.

de Souza, P. E., & Ferreira, R. L. (2025). Oscillating in darkness: Circadian rhythms of cave-dwelling scorpions. Chronobiology International, 1–8. https://doi.org/10.1080/07420528.2025.2596773