New Publication: Hybridisation in the Tarantula Hobby

  New Publication: Hybridisation in the Tarantula Hobby I am pleased to share the publication of my latest paper, “Hybridisation in the Tarantula Hobby: Ethical Boundaries and Biological Consequences,” in the Journal of the British Tarantula Society , Volume 41, No. 1, September 2026. The paper addresses an issue that deserves serious consideration within the tarantula community: hybridisation and its potential long-term effects on the integrity of captive lineages. More Than a Breeding Decision The tarantula hobby has changed considerably over the past several decades. What was once a relatively small community has grown into an international network of keepers, breeders, vendors, researchers, and societies. Captive breeding has contributed enormously to that growth, improving husbandry knowledge and increasing the availability of captive-bred animals. With that success comes responsibility for the lineages we maintain. Hybridisation may seem like an isolated breeding experiment,...

Thieves and freeloaders: Argyrodine kleptoparasites invading cobwebs (Theridiidae) in the arid south-western USA

 


Thieves and freeloaders: Argyrodine kleptoparasites invading cobwebs (Theridiidae) in the arid south-western USA

Abstract

Obligate argyrodine kleptoparasites (TheridiidaeAraneae) exploit heterospecific spider webs for food and shelter. Argyrodine spiders are a model lineage for the study of kleptoparasitism and related strategies, yet data on the behaviour of the majority of the over 250 argyrodine species is lacking. Here, we help fill that knowledge gap by documenting the natural history of two poorly-known species. We studied Argyrodes pluto and Neospintharus baboquivari in the webs of two other cobweb spiders, the western black widow (Latrodectus hesperus) and Tidarren sisyphoides, across four sites in southern Arizona. Argyrodes pluto completes its life cycle in L. hesperus webs and specialises on host egg sacs, displacing them to the periphery and feeding on eggs and juveniles; this behaviour appears essential for its reproduction. Neospintharus baboquivari occurs gregariously in both host webs, gleaning small prey. In contrast, N. baboquivari is reportedly a solitary araneophage in the colonial orb webs of Philoponella oweni. We quantified egg sac displacement and describe foraging, mating, egg sac construction and interactions with parasitoids and predators. These findings reveal novel natural history information and expand our understanding of argyrodine behavioural plasticity.

Cowles J, Agnarsson I (2025) Thieves and freeloaders: Argyrodine kleptoparasites invading cobwebs (Theridiidae) in the arid south-western USA. Biodiversity Data Journal 13: e172851. https://doi.org/10.3897/BDJ.13.e172851