New predatory interaction of Trichonephila clavipes (Araneae: Nephilidae) on Fidicinini (Hemiptera: Cicadidae) in a forest fragment of the Neotropical region

Posted by
  New predatory interaction of Trichonephila clavipes (Araneae: Nephilidae) on Fidicinini (Hemiptera: Cicadidae) in a forest fragment of the Neotropical region Abstract Trichonephila clavipes (Araneae: Nephilidae) is an orb web-building spider whose diet is primarily based on flying insects. This note aims to report the first predatory interaction of T. clavipes on a cicada of the genus Fidicina (Hemiptera: Cicadidae) in a fragment of the Atlantic Forest in Brazil. The predation event was observed (ad libitum) in the Benjamin Maranhão Botanical Garden situated in the Mata do Buraquinho Wildlife Refuge, northeastern Brazil. A specimen of Fidicina sp. was found freshly dead and trapped in the web of T. clavipes. The nephilid was observed moving slowly between the ventral and dorsal regions of the Fidicina sp. without weaving a web around the cicadid. Then, T. clavipes was observed perched on the left side of the Fidicina sp., with its pedipalps and chelicerae manipulating the thorax ...

Is spider resting metabolic rate more strongly associated with ecological guild or extreme habitat conditions?

Posted by

 


Is spider resting metabolic rate more strongly associated with ecological guild or extreme habitat conditions?

Abstract

Ectotherms with lower maintenance costs and broader environmental tolerances are generally more resilient in human-altered landscapes and under current climate change, enhancing their chances of survival and colonization. In this study, we explored how habitat use and foraging strategy are associated with the resting metabolic rate (RMR) of spiders from habitats with significant temperature variability due to anthropogenic disturbance: native forests and young pine plantations, both in the Southern Atlantic Forest. Using open-flow respirometry at 25°C, we measured CO2 production in immobile spiders to calculate their RMR. Key findings include: (1) all spiders showed 22%–57% lower RMR than predicted by standard metabolic equations; (2) continuous gas exchange patterns, typical of mesic-adapted species, were observed in all cases; (3) the metabolic rate scaling exponent was 0.65; (4) there were no significant RMR differences between habitats, but a negative correlation between RMR and microhabitat thermal amplitude was noted; and (5) active foragers had higher RMRs than passive foragers. These findings enhance our understanding of spider biology, physiology, and ecology, particularly in their responses to anthropogenic stressors.

G. Piñanez Espejo, Y. M., Munévar, A., Zurita, G. A., & Schilman, P. E. (2025). Is spider resting metabolic rate more strongly associated with ecological guild or extreme habitat conditions? Ecology, 106(10), e70231. https://doi.org/10.1002/ecy.70231