A Remarkable Discovery: Exploring a Rare Eresus and Spider Wasp Interaction

  Photo Credit: © Antonino Rametta . All photographs are used with permission. No part of these images may be reproduced, distributed, or used in any form without the prior written permission of the photographer. A Remarkable Discovery: Exploring a Rare Eresus and Spider Wasp Interaction One of the most rewarding aspects of maintaining Arácnido Taxonomy is hearing from naturalists and photographers around the world who take the time to share their discoveries. Every so often, an email arrives that immediately captures your attention. Not because it claims to rewrite what we know about biodiversity, but because it documents something that very few people have the opportunity to witness. Recently, I was contacted by a naturalist in Sicily who shared a series of exceptionally high-quality photographs of a female ladybird spider ( Eresus ) during what appeared to be an interaction with a spider wasp. Along with the images came a simple question: "Could this be scientifically import...

Arthropod-related vehicle collisions increase harvestmen populations along road verges

 


Arthropod-related vehicle collisions increase harvestmen populations along road verges

Abstract

The expansion of road networks has been instrumental in facilitating human mobility and economic development. However, this infrastructure presents significant challenges to ecological systems. While most research focusses on the ecology of vertebrates, the potential effects on invertebrates remain understudied. This study investigated the impact of roads on the abundance and diversity of ground-dwelling arthropods, specifically harvestmen (Arachnida: Opiliones) and ground beetles (Coleoptera: Carabidae). The results showed that the distance from the road positively influenced the abundance (but not diversity) of beetles, while both the abundance and diversity of the harvestmen were highest near the roads. Further analysis revealed that dead insects were significantly more common near high-speed road sections compared to low-speed sections, probably due to increased road collisions. The abundance of harvestmen (but not beetles) was significantly affected by the presence of dead insects. Mediation analysis showed that high speed roads influence harvestmen abundance indirectly through its effect on dead insects abundance. It seems that the carabid beetles avoided the high-speed sections of the roads. Our findings suggest that roads causes mortality of flying insects via collisions but also serve as an important food source for scavengers such as harvestmen. Thus, road collisions with arthropods generate conditions similar to those observed for vertebrate scavengers feeding on roadkill.
Litavský, J., Prokop, P., Majzlan, O., & Žarnovičan, H. (2025). Arthropod-related vehicle collisions increase harvestmen populations along road verges. Acta Oecologica, 128, 104114. https://doi.org/10.1016/j.actao.2025.104114