Role of the inflammatory response in the hemorrhagic syndrome induced by the hemolymph of the caterpillar Lonomia achelous

Urban biodiversity: Cuterebriasis in free-ranging Robinson's mouse opossum (Marmosa robinsoni) in the suburbs of Barranquilla, Colombia

The tropical dry forest is one of the world's most threatened ecosystems and is the habitat of the Robinson's Mouse Opossum (Marmosa robinsoni), a small marsupial within the Didelphidae family. This study aimed to describe cases of cuterebriases in free-ranging M. robinsoni by examining individuals caught in live animal traps. Sherman traps were deployed in four different sites over three different periods in five days. All animals passed through biometry, weighing, sampling parasites, and sampling feces. Only animals captured in the study site located close to the city were anesthetized and examined. The evaluation included blood samples and a clinical examination. Animals received anesthesia under physical restraint by intramuscular injections of ketamine and xylazine. For anesthetic reversion, the protocol was Yohimbine administered before release. In total, 8% (5/60) of all captured animals had fly larvae extracted from wounds. The molecular Barcode of the mitochondrial Cytochrome Oxidase I gene showed no match with any recognized species of Cuterebra. The animals weighed from 35 to 80 g and had lesions in the scapular region with parasites under their skin in sizes ranging from 1.3 to 2.2 cm. The animals with parasites were in good physical condition without evidence of disturbances in health conditions. This is compatible with literature, reporting little effect on population dynamics of other host species infected with Cuterebra larvae. The study included 24 animals captured in three areas far from any city, which showed no evidence of cuterebrid infection, suggesting that proximity to the city could increase exposure to cuterebriasis. There are reports of cuterebrids in M. robinsoni in Brazil; however, this is the first report of cuterebriasis in M. robinsoni in Colombia.

Venomous caterpillars: From inoculation apparatus to venom composition and envenomation

Envenomation by the larval or pupal stages of moths occurs when the victim presses their hairs. They penetrate the subcutaneous tissue, releasing toxins such as proteolytic enzymes, histamine and other pro-inflammatory substances. Cutaneous reactions, including severe pain, oedema and erythema are frequent local manifestations of caterpillar envenomation, but, in some cases, the reactions can evolve into vesicles, bullae, erosions, petechiae, superficial skin necrosis and ulcerations. Alternatively, some individual can develop allergic reactions, renal failure, osteochondritis, deformity and immobilization of the affected joints and intracerebral bleeding. Caterpillars produce venom to protect themselves from predators; contact with humans is accidental and deserves close attention. Their venoms have not been well studied, except for toxins from some few species. The present review brings together data on venomous caterpillars of moths, primarily addressing the available literature on diversity among the different families that cause accident in humans, the structures used in their defense, venom composition and clinical aspects of the envenomations. Understanding the molecular mechanisms of action of caterpillars' toxins may lead to the development of more adequate treatments.