Widow spiders in the New World: a review on Latrodectus Walckenaer, 1805 (Theridiidae) and latrodectism in the Americas

Humankind has always been fascinated by venomous animals, as their toxic substances have transformed them into symbols of power and mystery. Over the centuries, researchers have been trying to understand animal venoms, unveiling intricate mixtures of molecules and their biological effects. Among venomous animals, Latrodectus Walckenaer, 1805 (widow spiders) have become feared in many cultures worldwide due to their extremely neurotoxic venom. The Latrodectus genus encompasses 32 species broadly spread around the globe, 14 of which occur in the Americas. Despite the high number of species found in the New World, the knowledge on these spiders is still scarce. This review covers the general knowledge on Latrodectus spp. from the Americas. We address widow spiders' taxonomy; geographical distribution and epidemiology; symptoms and treatments of envenomation (latrodectism); venom collection, experimental studies, proteome and transcriptome; and biotechnological studies on these Latrodectus spp. Moreover, we discuss the main challenges and limitations faced by researchers when trying to comprehend this neglected group of medically important spiders. We expect this review to help overcome the lack of information regarding widow spiders in the New World.(AU)

Widow spiders in the New World: a review on Latrodectus Walckenaer, 1805 (Theridiidae) and latrodectism in the Americas

Humankind has always been fascinated by venomous animals, as their toxic substances have transformed them into symbols of power and mystery. Over the centuries, researchers have been trying to understand animal venoms, unveiling intricate mixtures of molecules and their biological effects. Among venomous animals, Latrodectus Walckenaer, 1805 (widow spiders) have become feared in many cultures worldwide due to their extremely neurotoxic venom. The Latrodectus genus encompasses 32 species broadly spread around the globe, 14 of which occur in the Americas. Despite the high number of species found in the New World, the knowledge on these spiders is still scarce. This review covers the general knowledge on Latrodectus spp. from the Americas. We address widow spiders' taxonomy; geographical distribution and epidemiology; symptoms and treatments of envenomation (latrodectism); venom collection, experimental studies, proteome and transcriptome; and biotechnological studies on these Latrodectus spp. Moreover, we discuss the main challenges and limitations faced by researchers when trying to comprehend this neglected group of medically important spiders. We expect this review to help overcome the lack of information regarding widow spiders in the New World.(AU)

Widow spiders in the New World: a review on Latrodectus Walckenaer, 1805 (Theridiidae) and latrodectism in the Americas

Abstract Humankind has always been fascinated by venomous animals, as their toxic substances have transformed them into symbols of power and mystery. Over the centuries, researchers have been trying to understand animal venoms, unveiling intricate mixtures of molecules and their biological effects. Among venomous animals, Latrodectus Walckenaer, 1805 (widow spiders) have become feared in many cultures worldwide due to their extremely neurotoxic venom. The Latrodectus genus encompasses 32 species broadly spread around the globe, 14 of which occur in the Americas. Despite the high number of species found in the New World, the knowledge on these spiders is still scarce. This review covers the general knowledge on Latrodectus spp. from the Americas. We address widow spiders taxonomy; geographical distribution and epidemiology; symptoms and treatments of envenomation (latrodectism); venom collection, experimental studies, proteome and transcriptome; and biotechnological studies on these Latrodectus spp. Moreover, we discuss the main challenges and limitations faced by researchers when trying to comprehend this neglected group of medically important spiders. We expect this review to help overcome the lack of information regarding widow spiders in the New World.

The History of Venomous Spider Identification, Venom Extraction Methods and Antivenom Production: a Long Journey at the Butantan Institute, São Paulo, Brazil

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.(AU)

The history of venomous spider identification, venom extraction methods and antivenom production: a long journey at the Butantan Institute, São Paulo, Brazil

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.(AU)

The history of venomous spider identification, venom extraction methods and antivenom production: a long journey at the Butantan Institute, São Paulo, Brazil

The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.

First report of brown widow spider sightings in Peninsular Malaysia and notes on its global distribution

Background:The brown widow spider (Latrodectus geometricus Koch, 1841) has colonised many parts of the world from its continent of origin, Africa. By at least 1841, the species had successfully established populations in South America and has more recently expanded its range to the southern states of North America. This highly adaptable spider has been far more successful in finding its niche around the world than its famous cousins, the black widow, Latrodectus mactans, found in the south-eastern states of North America, and the red-back, Latrodectus hasselti, found mostly in Australia, New Zealand and Japan.Methods:We performed an extensive web search of brown widow sightings and mapped the location of each sighting using ArcGIS. Specimens reputedly of the species L. geometricus were collected at three localities in Peninsular Malaysia. The spiders were identified and documented based on an examination of morphological characteristics and DNA barcoding.Results:The spiders found in Peninsular Malaysia were confirmed to be Latrodectus geometricus based on their morphological characteristics and DNA barcodes. We recorded 354 sightings of the brown widow in 58 countries, including Peninsular Malaysia.Conclusion:Reports from the Americas and the Far East suggest a global-wide invasion of the brown widow spider. Herein we report the arrival of the brown widow spider in Peninsular Malaysia and provide notes on the identification of the species and its recently expanded range.(AU)

First report of brown widow spider sightings in Peninsular Malaysia and notes on its global distribution

Background: The brown widow spider (Latrodectus geometricus Koch, 1841) has colonised many parts of the world from its continent of origin, Africa. By at least 1841, the species had successfully established populations in South America and has more recently expanded its range to the southern states of North America. This highly adaptable spider has been far more successful in finding its niche around the world than its famous cousins, the black widow, Latrodectus mactans, found in the south-eastern states of North America, and the red-back, Latrodectus hasselti, found mostly in Australia, New Zealand and Japan. Methods: We performed an extensive web search of brown widow sightings and mapped the location of each sighting using ArcGIS. Specimens reputedly of the species L. geometricus were collected at three localities in Peninsular Malaysia. The spiders were identified and documented based on an examination of morphological characteristics and DNA barcoding. Results: The spiders found in Peninsular Malaysia were confirmed to be Latrodectus geometricus based on their morphological characteristics and DNA barcodes. We recorded 354 sightings of the brown widow in 58 countries, including Peninsular Malaysia. Conclusion: Reports from the Americas and the Far East suggest a global-wide invasion of the brown widow spider. Herein we report the arrival of the brown widow spider in Peninsular Malaysia and provide notes on the identification of the species and its recently expanded range.(AU)

First report of brown widow spider sightings in Peninsular Malaysia and notes on its global distribution

Background: The brown widow spider (Latrodectus geometricus Koch, 1841) has colonised many parts of the world from its continent of origin, Africa. By at least 1841, the species had successfully established populations in South America and has more recently expanded its range to the southern states of North America. This highly adaptable spider has been far more successful in finding its niche around the world than its famous cousins, the black widow, Latrodectus mactans, found in the south-eastern states of North America, and the red-back, Latrodectus hasselti, found mostly in Australia, New Zealand and Japan. Methods: We performed an extensive web search of brown widow sightings and mapped the location of each sighting using ArcGIS. Specimens reputedly of the species L. geometricus were collected at three localities in Peninsular Malaysia. The spiders were identified and documented based on an examination of morphological characteristics and DNA barcoding. Results: The spiders found in Peninsular Malaysia were confirmed to be Latrodectus geometricus based on their morphological characteristics and DNA barcodes. We recorded 354 sightings of the brown widow in 58 countries, including Peninsular Malaysia. Conclusion: Reports from the Americas and the Far East suggest a global-wide invasion of the brown widow spider. Herein we report the arrival of the brown widow spider in Peninsular Malaysia and provide notes on the identification of the species and its recently expanded range.

AVALIAÇÃO DOS EFEITOS HISTOPATOLÓGICOS EM CAMUNDONGOS INDUZIDOS PELO VENENO DA ESPÉCIE BRASILEIRA DE VIÚVA NEGRA, LATRODECTUS CURACAVIENSIS E, DA CAPACIDADE PROTETORA DO SORO ANTILATRODÉCTICO.

Esse estudo avaliou, através da análise histológica de órgãos de camundongos e sintomatologia, os efeitos tóxicos induzidos pelo veneno da espécie brasileira de viúva negra, Latrodectus curacaviensis, e a capacidade protetora do soro antilatrodéctico. Foram avaliados 40 camundongos Mus musculus Swiss, divididos em quatro grupos: (1) camundongos inoculados com veneno latrodéctico, (2) camundongos inoculados com soro antilatrodéctico, (3) camundongos inoculados com veneno latrodéctico e tratados com soro antilatrodéctico; e (4) camundongos inoculados apenas com solução salina 0,85% estéril, sendo este o controle. Foi realizada uma análise sintomatológica com posterior eutanásia e necropsia dos animais para análise histopatológica do cérebro, pulmão, fígado e rim. Este estudo evidenciou que o veneno de Latrodectus curacaviensis, em modelo animal, apresentou sintomatologia característica de latrodectismo e causou danos hepáticos, renais, pulmonares e cerebrais, tais como: no fígado, degeneração macro/micro vacuolar, anisocariose, inflamação e necrose; no cérebro e cerebelo apresentou congestão e edema; no pulmão foi observado congestão, edema, enfisema, inflamação e hemorragia; no rim apresentou congestão, degeneração tubular, inflamação e hemorragia. O grupo inoculado apenas com o soro antilatrodéctico e o grupo controle apresentaram algumas alterações histopatológicas, mas com menor relevância para o estudo. O grupo inoculado com veneno e soro (soroneutralização) apresentou alterações histopatológicas, mas com menor intensidade em relação ao grupo administrado apenas com o veneno. Concluímos que o soro antilatrodéctico foi eficiente em minimizar os efeitos do veneno uma vez que houve aumento da sobrevida dos animais, redução dos danos histopatológicos e, principalmente, redução dos sintomas decorrentes do envenenamento.

This study evaluated, through the histological analysis of mouse organs and symptomatology, the toxic effects induced by the venom of the Brazilian black widow, Latrodectus curacaviensis, and the eficacy of the anti-Latrodectus antivenom.Fourteen Mus Musculus Swiss mice were evaluated, divided into four groups: (1) mice inoculated with latrodectic venom, (2) mice inoculated with antiLatrodectus antivenom, (3) mice inoculated with latrodectic venom and treated with anti- Latrodectus antivenom; and (4) mice inoculated only with 0.85% sterile saline solution, which is the control. A symptomatic analysis was performed with subsequent euthanasia and necropsy of the animals for histopathological analysis of the brain, lung, liver and kidney.This study showed that the venom of Latrodectus curacaviensis, in an animal model, presented characteristic symptoms of latrodectism and caused hepatic, renal, pulmonary and cerebral damages, such as: in the liver, macro / micro vacuolar degeneration, anisocariose, inflammation and necrosis; in the brain and cerebellum presented congestion and edema; congestion, edema, emphysema, inflammation and haemorrhage were observed in the lung; in the kidney presented congestion, tubular degeneration, inflammation and hemorrhage.The group inoculated with anti-Latrodectus antivenom alone and the control group presented some histopathological alterations, but with less relevance to the study. The group inoculated with venom and serum (seroneutralization) presented histopathological alterations, but with less intensity than the group administered only with the venom. We conclude that antiLatrodectus antivenom was efficient in minimizing the effects of venom since there was an increase in the survival of the animals, reduction of the histopathological damages and, mainly, reduction of the symptoms due to the envenomation.

Envenomation caused by Latrodectus geometricus in São Paulo state, Brazil: a case report

Widow spiders (Latrodectus spp.), also known as "black widows", have a worldwide distribution and can cause latrodectism. To the best of our knowledge, in Brazil, only one case of Latrodectus geometricus (Koch, 1841) envenomation in a human has been reported. The aim of the present report is to describe a spider bite caused by Latrodectus geometricus in a patient who lives in Paranapanema, São Paulo state, Brazil.(AU)

Envenomation caused by Latrodectus geometricus in São Paulo state, Brazil: a case report

Widow spiders (Latrodectus spp.), also known as "black widows", have a worldwide distribution and can cause latrodectism. To the best of our knowledge, in Brazil, only one case of Latrodectus geometricus (Koch, 1841) envenomation in a human has been reported. The aim of the present report is to describe a spider bite caused by Latrodectus geometricus in a patient who lives in Paranapanema, São Paulo state, Brazil.