Toxungen

 ( Animal Physiology ) 

Toxungen use possibly also exists in , as a number of species deploy defensive secretions from their stomachs, , or cloacas, and some anoint themselves with heterogenously acquired chemicals from , , , plant materials, and even manufactured .J.P. Dumbacher and Pruett-Jones, S. (1996). "Avian chemical defense". In: Nolan, V., Jr., and Ketterson, E. D. (Eds.), Current Ornithology, vol. 13, Plenum Press, New York (1996), pp. 137-174. Morozov, N. S. (2015). Why do birds practice anting? Biology Bulletin Reviews, 5(4), 353-365. Some of the described substances may be toxic, at least to Parasitism, which would qualify them as toxungens.

Toxungen use might also exist in several mammal groups. (genus Nycticebus), which comprise several species of nocturnal primates in Southeast Asia, produce a secretion in their brachial glands (a scent gland near their armpit) that possesses apparent toxicity.Alterman, L. (1995). "Toxins and toothcombs: potential allospecific chemical defenses in Nycticebus and Perodicticus". In Alterman, L.; Doyle, G.A.; Izard, M.K (eds.). Creatures of the Dark: The Nocturnal Prosimians. New York, New York: Plenum Press. Pp. 413–424. . .Nekaris, K., Moore, R. S., Rode, E. J., & Fry, B. G. (2013). Mad, bad and dangerous to know: the biochemistry, ecology and evolution of slow loris venom. Journal of Venomous Animals and Toxins including Tropical Diseases, 19, 1-10. . .Nekaris, K. A. I., Campera, M., Nijman, V., Birot, H., Rode-Margono, E. J., Fry, B. G., ... & Imron, M. A. (2020). Slow lorises use venom as a weapon in intraspecific competition. Current Biology, 30(20), R1252-R1253. . . When the secretion is licked and combined with saliva, their bite introduces the secretion into a wound, which can cause sometimes severe tissue injury to conspecifics and other aggressors, thereby functioning as a venom. They can also rub the secretion on their fur or lick their offspring before stashing them in a secure location, thereby functioning potentially as a toxungen. and several other members of Mephitidae and Mustelidae spray a noxious and potentially injurious secretion from their anal sac when threatened.Stankowich, T., Caro, T., & Cox, M. (2011). Bold coloration and the evolution of aposematism in terrestrial carnivores. Evolution, 65(11), 3090-3099. . . High concentrations of the spray can be toxic,Wood, W. F. (1999). The history of skunk defensive secretion research. The Chemical Educator, 4(2), 44-50. . with rare accounts of spray victims suffering injury and even death.Zaks, K. L., Tan, E. O., & Thrall, M. A. (2005). Heinz body anemia in a dog that had been sprayed with skunk musk. Journal of the American Veterinary Medical Association, 226(9), 1516-1518. . .Fierro, B. R., Agnew, D. W., Duncan, A. E., Lehner, A. F., & Scott, M. A. (2013). Skunk musk causes methemoglobin and Heinz body formation in vitro. Veterinary Clinical Pathology, 42(3), 291-300. . .

Although the extinct theropod Dilophosaurus was portrayed in the original Jurassic Park and Jurassic World Dominion films as capable of spitting a toxic secretion, no evidence exists to suggest that any dinosaur possessed either a toxungen or venom. Carter, N. Undated. "The real Dilophosaurus." At Blogosaur, Phillip J. Curie Dinosaur Museum.

Toxins used as toxungens can be acquired by several means. Many species synthesize their own toxins and store them within glands, but others acquire their toxins exogenously from other species. Two examples illustrate exogenous acquisition. Snakes of the genus Rhabdophis sequester their nuchal gland toxins from their diet of and/or Firefly,Hutchinson, D. A., Mori, A., Savitzky, A. H., Burghardt, G. M., Wu, X., Meinwald, J., & Schroeder, F. C. (2007). "Dietary sequestration of defensive steroids in nuchal glands of the Asian snake Rhabdophis tigrinus". Proceedings of the National Academy of Sciences, 104(7), 2265-2270. . PMID: 17284596.Fukuda, M., & Mori, A. (2021). "Does an Asian natricine snake, Rhabdophis tigrinus, have chemical preference for a skin toxin of toads?" Current Herpetology, 40(1), 1-9. doi: . Blue-ringed octopuses (genus Hapalochlaeana) acquire tetrodotoxin, the highly toxic non-proteinaceous component of their salivary glands that can be ejected into the water to subdue nearby prey, via accumulation from food resources and/or symbiotic tetrodotoxin-producing bacteria.Sutherland, S. & Lane, W. (1969). "Toxins and mode of envenomation of the common ringed or blue-banded octopus". Medical Journal of Australia 1, 893–898. . PMID: 4977737.Yamate, Y., Takatani, T., & Takegaki, T. (2021). "Levels and distribution of tetrodotoxin in the blue-lined octopus Hapalochlaena fasciata in Japan, with special reference to within-body allocation." Journal of Molluscan Studies, 87(1), eyaa042. doi: [15].

Toxungens are most commonly used for defensive purposes, but can be used in other contexts as well. Examples of toxungen use for predation include the blue-ringed octopus, which can squirt its secretion into water to immobilize or kill its prey,Sutherland, S. & Lane, W. (1969). "Toxins and mode of envenomation of the common ringed or blue-banded octopus". Medical Journal of Australia 1, 893–898. . PMID: 4977737. and ants of the genus Crematogaster that cooperatively subdue their prey by seizing, spread-eagling, and then smearing their toxins onto the prey's surface.Richard, F. J., Fabre, A. & Dejean, A. (2001). "Predatory behavior in dominant arboreal ant species: the case of Crematogaster sp. (Hymenoptera: Formicidae)". Journal of Insect Behavior 14, 271–282. . Toxungens can also be used for communication and hygiene. Many possess a secretion used as a venom (injected for predation and/or defense) that can also be sprayed to communicate alarm among nestmates, to mark a trail used for food gathering, or to keep their brood free of parasites.Nelsen, D. R., Nisani, Z., Cooper, A. M., Fox, G. A., Gren, E. C., Corbit, A. G., & Hayes, W. K. (2014). "Poisons, toxungens, and venoms: redefining and classifying toxic biological secretions and the organisms that employ them". Biological Reviews, 89(2), 450-465. . PMID: 24102715.

Because of their unique delivery system, toxungens may be chemically designed to better penetrate body surfaces. Arthropods that spray or smear their secretion onto insect prey enhance toxin penetration by including a spreading agent that additionally enhances toxicity.Eisner, T., Meinwald, J., Monro, A. & Ghent, R. (1961). "Defence mechanisms of Arthropods. I. The composition and function of the spray of the whipscorpion, Mastigoproctus giganteus (Lucas)(Arachnida, Pedipalpida)". Journal of Insect Physiology 6, 272–298. .Prestwich, G. D. (1984). "Defense-mechanisms of termites". Annual Review of Entomology 29, 201–232. .Eisner, T., Rossini, C. & Eisner, M. (2000b). "Chemical defense of an earwig ( Doru taeniatum)". Chemoecology 10, 81–87. . Some have modified their secretion so that the cardiotoxins are more injurious to eye membranes.Ismail,M., Al-Bekairi, A.M., El-Bedaiwy, A.M. & Abd-El Salam,M. A. (1993). "The ocular effect of spitting cobras: II. Evidence that cardiotoxins are responsible for the corneal opacification syndrome". Clinical Toxicology 31, 45–62. . PMID: 8433415.