Venom induced pressure elevation reversible syndrome: a severe pediatric rattlesnake envenomation, evidence for conservative management, and call for naming the syndromeVenom induced pressure elevation reversible syndrome: a severe pediatric rattlesnake envenomation, evidence for conservative management, and call for naming the syndrome

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  Venom induced pressure elevation reversible syndrome: a severe pediatric rattlesnake envenomation, evidence for conservative management, and call for naming the syndromeVenom induced pressure elevation reversible syndrome: a severe pediatric rattlesnake envenomation, evidence for conservative management, and call for naming the syndrome Abstract Introduction : Rattlesnake envenomation frequently mimics traumatic compartment syndrome, as both are characterized by severe pain, swelling, and elevated compartment pressures. Unlike traumatic compartment syndrome there have been no documented cases of ischemic limb injury after envenomated patients have received antivenom. Furthermore, there is experimental evidence that fasciotomy worsens myonecrosis. This has led medical toxicologists and surgical guidelines to shift from liberally recommending fasciotomy to near universal recommendation of antivenom alone. Despite this, fasciotomies continue to be recommended and performed on rattle...

Circadian rhythms of locomotor activity in the New World tarantula Neoholothele incei (Araneae: Theraphosidae)

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Circadian rhythms of locomotor activity in the New World tarantula Neoholothele incei (Araneae: Theraphosidae)

Abstract

Circadian rhythms in behavior are intrinsically linked to organismal fitness, supporting the theory that Earth’s near 24 h day selects against dissonant rhythms. However, in arthropods, particularly spiders, circadian free-running periods (FRPs) exhibit significant population variation. Some spider species possess rhythms that deviate by up to 5–6 h from 24 h. These findings are restricted to a large clade of web-building spiders, leaving it unknown whether this chronobiological strategy extends beyond that group. To explore this, we monitored the locomotor activity of a distant outgroup species, the New World tarantula Neoholothele incei F.O. Pickard-Cambridge, under a controlled photic cycle. Our efforts determined that its bimodal diel activity is governed by circadian (endogenous) components. Spiders usually had both a diurnal and nocturnal peak in locomotor activity. Each peak showed strong support for its regulation by endogenous circadian control under constant conditions. FRPs averaged within an hour of 24 h but ranged from ~ 21 to 25 h, similar to the variation observed in some insects and spiders. These results offer initial evidence that FRP variation, though not always extreme deviations from 24 h, is a common strategy among spiders.

Giulian, J., Toporikova, N., Petko, J. et al. Circadian rhythms of locomotor activity in the New World tarantula Neoholothele incei (Araneae: Theraphosidae). J Ethol (2025). https://doi.org/10.1007/s10164-025-00842-y