DNA barcoding of scorpions from Kosovo, with the first record of Alpiscorpius dinaricus (Di Caporiacco) (Scorpiones: Euscorpiidae)

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  DNA barcoding of scorpions from Kosovo, with the first record of Alpiscorpius dinaricus (Di Caporiacco) (Scorpiones: Euscorpiidae) ABSTRACT This study presents DNA barcoding data for Alpiscorpius dinaricus (Di Caporiacco) and Euscorpius hadzii Caporiacco. Barcode sequences were compared with publicly available reference data to support species identification, together with the evaluation of diagnostic morphological characters. Alpiscorpius dinaricus is recorded from Kosovo for the first time, representing a new national record and contributing to the knowledge of euscorpiid diversity in the region. Diagnostic illustrations of A. dinaricus are provided to facilitate reliable identification and to support future faunistic, taxonomic, and biogeographic studies. Euscorpius hadzii , previously known only from Prizren district, is now reported also from Bjeshkët e Nemuna Mountains (Western Kosovo). Geci, D., Ibrahimi, H., Bilalli, A., Musliu, M., Strohmeier, T., Koblmüller, S., … S...

How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders

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How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders

Abstract

All animal species, from arthropods to vertebrates, must deal with occasional stressors in their lives, though most research on this has been focused on vertebrates. Meanwhile, our understanding of stress reactions in arthropod species like spiders is nascent. In the United States, a non-native orb-weaving spider, Trichonephila clavata (‘jorō’ spider), is spreading as is its already-established cousin in the United States, T. clavipes (golden silk spider). Prior study has revealed how these two species have a unique behavioural reaction to physical stressors, whereby they remain in a thanatosis state for a prolonged period compared with other species. Here, we investigate the physiological stress reactions of these Trichonephila spiders by evaluating how each species' dorsal vessel contractions (heart rates) become elevated after being subjected to a non-lethal stressor. For comparison, we also evaluate two similarly-sized orb weavers, Argiope aurantia (garden spider) and A. trifasciata (banded garden spider). We record baseline heart rates of inactive, resting, spiders in our lab, then restrain them under an electronic, ‘optocardiographic’, sensor for 10 min, to record their ‘stressed’ heart rates. Argiope aurantia has a pronounced heart rate elevation, for reasons unknown. We observe that all spider heart rates increase during restraint, though each has a species-specific pattern of elevation over time under restraint. Notably, heart rates of both Trichonephila spiders are less variable under stress, since they tend not to struggle during restraint. Meanwhile, both Argiope spiders frequently struggle, leading to marked fluctuations in cardiac output. The stress reactions of Trichonephila spiders could be characterized as ‘even-tempered’, which may factor into their ability to live in habitats with frequent disturbances.

Davis, A. K., & Vu, C. How to give a spider a heart attack: Evaluating cardiac stress reactions of Trichonephila and Argiope spiders. Physiological Entomology. https://doi.org/10.1111/phen.12463