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Clonal lineages in similar environments may be influenced by non-Mendelian inheritance, such as maternal age effects and developmental instabilities. These mechanisms may affect the developmental fitness of parthenogenetic litters. In this study, the scorpion Tityus stigmurus (Thorell, 1876) was used to analyze the effects of non-Mendelian variation on parthenogenetic litters. A total of 75 juveniles from five females were reared under the same controlled conditions, while their development was observed and evaluated through differences in offspring fitness traits (litter size, prosoma size, developmental time, and mortality) between the litters. First and second litters had a similar litter size, although second litters exhibited longer developmental time in the early instar stages (second and third) than first litters. These results indicate that T. stigmurus females allocated nutrient resources to maximize litter size rather than developmental fitness in subsequent litters. Differences in developmental time found in early instars but not in late instars may have occurred as a result of stochastic developmental variations in young individuals. Such variation in duration of development has the potential to influence survival of juveniles in natural environments because individuals that grow faster may avoid large predators and consume larger prey, compared to those that do not.

Fear level and intraguild predation are factors that act together to directly influence animal behavior, population dynamics, and community structure. These factors trigger stress, which promotes behavioral, morphological, physiological, and demographic changes, especially in the prey. Some invertebrates, such as scorpions, are known to have a refined chemoreception system to perceive both prey and predators. Therefore, we investigated the ability of an intraguild prey, the scorpion Ananteris mauryi Lourenço, 1982, to detect chemical traces of its predator, the scorpion Tityus pusillus Pocock, 1893. Our goal was to verify whether A. mauryi exhibits antipredator behavior induced exclusively by chemical cues from its predator. Ananteris mauryi specimens were subjected to two experimental treatments: one with and one without traces of T. pusillus. The results showed that A. mauryi tended to avoid substrates with chemical traces of T. pusillus, confirming its capacity for chemical detection. As a result of this perception, changes in behavioral frequencies were triggered, generating an antipredator behavioral repertoire. These findings were supported by behavioral changes, such as tail wagging, which is performed exclusively by scorpions in the presence of a predator and at imminent risk of predation.