Tityus serrulatus
Brazil's most dangerous scorpion, responsible for the most fatal stings.
Tityus serrulatus, the Brazilian yellow scorpion, is a species of scorpion of the family Buthidae. It is native to Brazil, and its venom is extremely toxic. It is the most dangerous scorpion in South America and is responsible for the most fatal cases.
- field
- Arachnology
- nationality
- Brazilian
- known_for
- Most dangerous scorpion in South America; responsible for the most fatal scorpion stings in Brazil
- length
- 5–7 cm (2–3 in)
- venom_LD50
- 26–51.6 μg/kg depending on geographic origin
Lore & Background
Tityus serrulatus is endemic to Brazil and widely found throughout the country, including states such as Alagoas, Bahia, Ceará, São Paulo, and many others. Adult specimens typically measure between 5–7 cm in length, with pale-yellow legs and pedipalps and a darker yellowish-brown trunk and tail tip. Like other Buthidae, it has a bulbous, segmented tail carried in a characteristic forward curve over the back, tipped with a venom-injecting barb. The species is usually parthenogenetic, meaning females can reproduce without males. It feeds on insects such as cockroaches and is suited to life in sewers and trash heaps in urban areas. Having a low metabolic rate, it can survive for months without eating. According to Rogério Bertani, a scientist and scorpion specialist at the Butantan Institute in São Paulo, deforestation and growing urbanization are causing this species to become more and more present. An abundance of prey, notably cockroaches, and shelter along with a lack of predators is believed to be a cause of the increase.
Reader's Guide
Tityus serrulatus is the most medically significant scorpion in Brazil, responsible for more accidents than any other scorpion in the country. In Brazil, scorpions cause the highest incidence of human envenomations of all venomous animals, more than snakes and spiders combined. With mortality rates ranging from 1.0 to 2.0% among children and elderly persons, T. serrulatus is responsible for more fatal cases than any other scorpion in South America. Most stings occur in urban areas, inside or near homes, with greater frequency in the south and southeast during warm and rainy months. Its venom contains TsIV, which slows the inactivation of sodium channels, and an excitatory neurotoxin that attacks the autonomic nervous system, causing a wide variety of symptoms including hyperglycemia, fever, priapism, tachycardia, hypertension, and pancreatitis. Death usually results from pulmonary edema and cardiorespiratory failure, occurring between 1–6 hours or 12–14 hours depending on age, health, and venom quantity. serrulatus believed responsible for the vast majority.
Did You Know?
- Tityus serrulatus is usually parthenogenetic, meaning females can reproduce without males.
- Its venom has different lethalities depending on geographic origin: LD50 of 51.6 μg/kg in Distrito Federal versus 26 μg/kg in Minas Gerais.
- The species can survive for months without eating due to its low metabolic rate.
Frequently Asked Questions
What is Tityus serrulatus?
Tityus serrulatus, commonly called the Brazilian yellow scorpion, is a species in the family Buthidae native to Brazil. It holds the distinction of being the most lethal scorpion in South America.
How toxic is Tityus serrulatus venom?
Its venom carries an LD50 between 26 and 51.6 micrograms per kilogram, with the exact figure shifting depending on the geographic origin of the specimen. This extreme potency is what makes it responsible for the majority of fatal scorpion stings in Brazil.
How large does Tityus serrulatus grow?
Adults typically measure roughly 5 to 7 centimeters (about 2 to 3 inches) in total length, placing them in the moderate-size range for scorpions despite their outsized danger to humans.
Why is Tityus serrulatus considered the most dangerous scorpion in South America?
Its venom is extraordinarily potent, and because the species is widespread across Brazil, it accounts for the highest number of fatal envenomations on the continent. No other South American scorpion combines that level of toxicity with the same frequency of human contact.
What family does Tityus serrulatus belong to?
It is classified in the family Buthidae, the same group that includes other highly venomous scorpions found across the Americas and other parts of the world.
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