Preying dangerously: black widow spider venom resistance in sympatric lizards

Abstract

Lizards and spiders are natural adversaries, yet little is known of adaptations that lizards might possess for dealing with the venomous defences of spider prey. In the Western USA, two lizard species ( Elgaria multicarinata and Sceloporus occidentalis ) are sympatric with and predate western black widow spiders ( Latrodectus hesperus ). The consequences of black widow spider venom (BWSV) can be severe, and are well understood for mammals but unknown for reptiles. We evaluated potential resistance to BWSV in the lizards that consume black widows, and a potentially susceptible species ( Uta stansburiana ) known as prey of widows. We investigated BWSV effects on whole-animal performance (sprint) and muscle tissue at two venom doses compared with control injections. Sprint speed was not significantly decreased in E. multicarinata or S. occidentalis in any treatment, while U. stansburiana suffered significant performance reductions in response to BWSV. Furthermore, E. multicarinata showed minimal tissue damage and immune response, while S. occidentalis and U. stansburiana exhibited increased muscle damage and immune system infiltration in response to BWSV. Our data suggest predator–prey relationships between lizards and spiders are complex, possibly leading to physiological and molecular adaptations that allow some lizards to tolerate or overcome the dangerous defences of their arachnid prey.

Natural toxins and One Health: a review

“…Spiders that inhabit grasslands and forests are the major contributors for spider-associated prey kills [ 154 ]. Remarkably, lizards are resistant to spider venom and even prey on spiders [ 16 ]. Centipedes can kill using their venom and feed on vertebrates, such as bats, rats, amphibians and reptiles [ 109 ].…”

“…The effects of insect toxins on the environment could be attributed to predator–prey relationships that could affect the delicate balance in the ecosystem [ 16 ]. Pigeons serve as food for hawks and falcons and play roles in seed dispersal.…”

“…Toxins also differ in terms of resistance to heat and sun, as some are heat labile while others are not, thereby affecting their bio-accumulation potential [ 15 ]. Some toxins are harmful to certain species while other species are unharmed by them, like the spider venom which is poisonous to many animals but not poisonous to lizards [ 16 ]. The major symptoms associated with natural toxin poisoning include nausea, pain, gastrointestinal disorders, cardiotoxicity, paralysis, hepatotoxicity and neurotoxicity [ [17] , [18] , [19] ].…”

Intersexual Differences in the Gene Expression of Phoneutria depilata (Araneae, Ctenidae) Toxins Revealed by Venom Gland Transcriptome Analyses

“…For example, recent studies on the composition of the venom of spiders of the genus Latrodectus suggest that the presence of molecules such as α-latrotoxin, a molecule acting specifically on the nervous system of vertebrates, could be related to the consumption of small reptiles and amphibians that are occasionally included in the diet of these spiders [ 36 ]. Conversely, the development of this strong toxin in the genus Latrodectus has been proposed as a defense mechanism against predators [ 37 ]. There are examples of spider species specialized in certain prey (e.g., myrmecophagy), in which the venom composition is simpler in comparison with generalist spiders, but the few toxins have a high affinity for and effectiveness upon their target prey [ 38 ].…”

“…For example, recent studies on the composition of the venom of spiders of the genus Latrodectus suggest that the presence of molecules such as α-latrotoxin, a molecule acting specifically on the nervous system of vertebrates, could be related to the consumption of small reptiles and amphibians that are occasionally included in the diet of these spiders [36]. Conversely, the development of this strong toxin in the genus Latrodectus has been proposed as a defense mechanism against predators [37].…”