"have marks and patterns that are attractive. Ctenids have a distinctive longitudinal groove on the top-rear of their oval carapace (some other spiders have a similar groove; e.g., Amaurobiidae). , the World Spider Catalog accepted the following genera: Wandering spider The wandering spiders are the members of the spider family Ctenidae. Some mistakenly misinterpret the name to only mean the genus ""Phoneutria"", which are often called Brazilian wandering spiders (despite several species with ranges outside Brazil), but wandering spiders better refers to the entire family Ctenidae. Some members of the genus ""Phoneutria"" are highly defensive and venomous nocturnal hunters, and"
"newspaper ""The Guardian"". He is a scientist and scorpion specialist at the Butantan Institute in São Paulo. ""I personally think that the problem will continue to grow."" Tityus serrulatus Tityus serrulatus, the Brazilian yellow scorpion, is a species of scorpion belonging to the family Buthidae. It is native to Brazil and its venom is extremely toxic. It is considered the most dangerous scorpion in Brazil. It is usually parthenogenetic. It has a diet of 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"
"Tityus serrulatus Tityus serrulatus, the Brazilian yellow scorpion, is a species of scorpion belonging to the family Buthidae. It is native to Brazil and its venom is extremely toxic. It is considered the most dangerous scorpion in Brazil. It is usually parthenogenetic. It has a diet of 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. ""Due to deforestation and growing urbanization, this species is becoming more and more present,"" according to Rogério Bertani in an interview with the British"
"6 μg intravenously and 134 μg subcutaneously as compared to 110 μg and 200 μg respectively for ""Latrodectus mactans"" (Southern black widow). This ranks ""Phoneutria"" venom among the most deadly spider venoms to mice. The Brazilian wandering spider's prey also includes crickets, katydids, mantids, and other larger animals, including tree frogs and lizards. The genus ""Phoneutria"" includes some of the relatively few species of spiders known to present a threat to humans. Danger to humans is not merely a question of toxicity, but requires the capacity to deliver the venom, a sufficient quantity of venom, a disposition that makes a"
"mg/kg. The Caspian cobra is the most venomous species of cobras in the world (to laboratory mice). The crude venom of ""N. oxiana"" produced the lowest known lethal dose (LCLo) of 0.005 mg/kg, the lowest among all cobra species ever recorded, derived from an individual case of poisoning by intracerebroventricular injection. After the Caspian and Philippine cobras, the forest cobra (N. melanoleuca) has an of 0.225 mg/kg subcutis, followed by the Samar cobra (""N. samarensis"") which has a value of 0.23 mg/kg subcutis. The water cobras of central Africa are also highly venomous. The murine intraperitoneal of ""Naja annulata"" and"
"fearsome reputations for their extreme aggression; ""Guinness World Records"" certifies the ant ""Myrmecia pyriformis"" as the world's most dangerous ant. The jack jumper have been compared to other highly aggressive ant species, such as ""Brachyponera chinensis"", ""Brachyponera sennaarensis"", and the red imported fire ant (""Solenopsis invicta""). The retractable sting is located in their abdomen, attached to a single venom gland connected by the venom sac, which is where the venom is accumulated. Exocrine glands are known in jack jumpers, which produce the venom compounds later used to inject into their victims. Their venom contains haemolytic and eicosanoid elements and histamines."
"its rediscovery in 1972. The inland taipan is the most venomous snake in the world. Based on the median lethal dose value in mice, its venom, drop for drop, is by far the most toxic of any snake – much more so than even sea snakes – and it has the most toxic venom of any reptile when tested on human heart cell culture. Unlike most snakes, the inland taipan is a specialist mammal hunter so its venom is specially adapted to kill warm-blooded species. It is estimated that one bite possesses enough lethality to kill at least 100 fully"
"Crotalus scutulatus Crotalus scutulatus (common names: Mojave rattlesnake, Mojave green,) is a highly venomous pit viper species found in the deserts of the southwestern United States and central Mexico. It is perhaps best known for its potent neurotoxic-hemotoxic venom, which is considered the world's most potent rattlesnake venom. Two subspecies are recognized, including the nominate subspecies described here. This species grows to an average of less than in length, with a maximum of . The color varies from shades of brown to pale green depending on the surroundings. The green hue found among Mojave rattlesnakes has led to them being"
"in the scientific literature. Like other rattlesnakes, however, they will defend themselves vigorously when disturbed. The Mojave rattlesnake is one of the world's most venomous snakes. The most common subspecies of Mojave rattlesnake (type A) has a neurotoxic venom that is considered to be the most debilitating and potentially deadly of all rattlesnakes, and even matching several elapids. However, chances for survival are very good if medical attention is sought as soon as possible after a bite. In people bitten by venom A Mojave rattlesnakes (those outside the relatively small Venom B area in south-central Arizona), the onset of serious"
"bodies in a weekly inoculation that potentially might protect them from the snake, though no scientific evidence supports this. Cobra stones or gems or pearls are believed to develop from the cobra's hood. King cobra The king cobra (""Ophiophagus hannah""), also known as the hamadryad, is a venomous snake species in the family Elapidae, endemic to forests from India through Southeast Asia. It is threatened by habitat destruction and has been listed as Vulnerable on the IUCN Red List since 2010. It is the world's longest venomous snake. Adult king cobras are long. The longest known individual measured . Despite"
"sequences showed it to be the sister species of the two previously known taipans. The two other described species of ""Oxyuranus"" are among the most venomous land snakes in the world - ""Oxyuranus microlepidotus"" ranked the most venomous land snake and ""Oxyuranus scutellatus"" the third most venomous after ""Pseudonaja textilis"". The new species, ""O. temporalis"", is likely to be extremely venomous given its close relationship to the other two species. As the new species is known from the single specimen, very little is known of its natural history, and nothing of its venom. In May 2010, a second specimen of"
"world's most venomous rattlesnake. Like the rinkhals, it can spit its venom. Its bite causes severe local tissue destruction (similar to that of the puff adder). Venom to the eyes can also cause impaired vision or blindness. The venom of this species contains postsynaptic neurotoxin and cytotoxin. There have been only a few fatalities resulting from bites of this species but survivors are mostly disfigured. A polyvalent antivenom is currently being developed by the Universidad de Costa Rica's Instituto Clodomiro Picado. This cobra's diet mainly consists of amphibians, other snakes, birds, eggs, small mammals, and occasionally even insects. This snake"
"fascicularis"") is 0.2 mg/kg. Higher figures were found for other experimental animals, such as 1.5 mg/kg for two-day-old mice. The average venom yield for a male is 176 mg. ""Guinness World Records"" has ranked the Sydney funnel-web as the world's most venomous spider, defining the term ""most venomous"" as ""having the venom most toxic to humans"", although it has also given this title to the Brazilian wandering spider. Funnel-web spider venom contains a compound known as atracotoxin, an ion channel inhibitor, which makes the venom highly toxic for humans and other primates. However, it does not affect the nervous system"
"vs intravenous vs intraperitoneal). As the mode can influence the relative number, venoms can only be compared within a mode. Otherwise, its apples and rocks."". Studies on mice and human cardiac cell culture shows that venom of the inland taipan, drop by drop, is the most toxic among all snakes; land or sea. The most venomous sea snake is actually Dubois' seasnake (""Aipysurus duboisii"" ). The belcher's sea snake is of moderate size, ranging from 0.5 to 1 meter (about 20–40 inches) in adult length. Its thin body is usually chrome yellowish in colour with dark greenish crossbands. The dorsal"
"the venom in at least some species of ""Hottentotta"" is relatively potent and can be of medical importance to humans. ""H. tamulus"", the Indian red scorpion, has evidently caused human fatalities by cardiovascular and pulmonary manifestations of intoxication and is considered the most lethal scorpion species in the world. Kleber et al. (1999) listed envenomation by at least four other species as to cause clinically significant symptoms. This listing is not comprehensive due to lack of data and all species of ""Hottentotta"" are potentially highly venomous to humans. Note that the LD value might differ considerably between populations of the"
"wildlife are threatened by some invasive species. There have been more than 300 documented invasive species in Brazil. It is estimated that invasive species cost Brazil around $49 billion. The most threatening species is the wild boar which destroys crops and natural flora, and can transmit diseases to indigenous animals. Also damaging the natural habitat are African grasses and snails. The Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) has put restrictions on what species may be brought into the country. Brazil is home to over 6% of the world's endangered species. According to a species assessment conducted by"
"tactics of Australian funnel-web spiders (family Atracidae) include fang display. Their venom, although they rarely inject much, has resulted in 13 attributed human deaths over 50 years. They have been deemed to be the world's most dangerous spiders on clinical and venom toxicity grounds, though this claim has also been attributed to the Brazilian wandering spider (genus ""Phoneutria""). There were about 100 reliably reported deaths from spider bites in the 20th century, compared to about 1,500 from jellyfish stings. Many alleged cases of spider bites may represent incorrect diagnoses, which would make it more difficult to check the effectiveness of"
"the breeding season is indefinite. ""Bitis nasicornis"" is considered to be one of the most dangerous snakes in Africa. Small doses of the snake's primarily hemotoxic venom can be deadly. This is unlike the Gaboon viper, the largest of the vipers, which uses a considerably larger amount of venom. ""Bitis nasicornis"" has both neurotoxic, as well as hemotoxic venom, as do most other venomous snakes. The hemotoxic venom in rhinoceros vipers is much more dominant. This venom attacks the circulatory system of the snake's victim, destroying tissue and blood vessels. Internal bleeding also occurs. When not in use, the rhino"
"Phyllobates Phyllobates is a genus of poison dart frogs native to Central and South America, from Nicaragua to Colombia. ""Phyllobates"" contains the most poisonous species of frog, the golden poison frog (""P. terribilis""). They are typical of the poison dart frogs, in that all species have bright warning coloration (aposematism), and have varying degrees of toxicity. Only species of ""Phyllobates"" are used by natives of South American tribes as sources of poison for their hunting darts. The most toxic of the many poisonous alkaloids these frogs emit from their skins is batrachotoxin, alongside a wide variety of other toxic compounds."
"Ts15 Ts15 (Tityustoxin-15; α-KTx 21.1) is produced by the Brazilian yellow scorpion ""Tityus serrulatus"". It targets voltage-gated potassium channels, primarily the subtypes Kv1.2 and Kv1.3. Ts15 can be isolated from the venom of ""Tityus serrulatus"", otherwise known as the Brazilian yellow scorpion. It is the deadliest scorpion toxin in Brazil, with a lethality rate of 0.15%. Ts15 is only one of many neurotoxins that can be found in the venom of ""Tityus serrulatus"". Ts15 is a peptide with a length of 36 amino acids, which are crosslinked by three disulfide bridges. The 27th position in the amino acid sequence undergoes"
"Eastern diamondback rattlesnake Crotalus adamanteus, commonly called the eastern diamondback rattlesnake, among other names, is a species of venomous pit viper in the family Viperidae. The species is endemic to the southeastern United States. It is the heaviest, though not the longest, venomous snake in the Americas and the largest rattlesnake. No subspecies are recognized. ""C. adamanteus"" is the largest rattlesnake species and is the heaviest known species of venomous snake, with one specimen shot in 1946 measuring in length and weighing . However, other venomous snakes may rival this species in weight. The much longer but more slender king"
"Ancylostoma braziliense Ancylostoma braziliense is a species of hookworm belonging to the genus ""Ancylostoma"". It is an intestinal parasite of domestic cats and dogs. Severe infection is often fatal to these pets, especially in puppies and kittens. The infection is particularly endemic in the southern United States. It is most often confused with the zoonotic hookworm species ""Ancylostoma ceylanicum"" because of their uncanny resemblance. ""A. braziliense"" larvae can cause accidental infection in humans called cutaneous larval migration or creeping eruption, which produces severe itching in the skin. It is the most common skin infection in tropical region, particularly along the"
"types may actually be separate, endangered species. Depletion of prey species, pollution, large-scale oil spills, and habitat disturbance caused by noise and conflicts with boats are the most significant worldwide threats. Like other animals at the highest trophic levels, the killer whale is particularly at risk of poisoning from bioaccumulation of toxins, including polychlorinated biphenyls (PCBs). European harbor seals have problems in reproductive and immune functions associated with high levels of PCBs and related contaminants, and a survey off the Washington coast found PCB levels in killer whales were higher than levels that had caused health problems in harbor seals."
"that of the Japanese giant hornet (""Vespa mandarinia japonica""), which has an LD of 4.0 mg/kg, but which is responsible for many more human deaths than ""Vespa luctuosa"". The greater lethality of Japanese giant hornet stings—as well as the closely related Asian giant hornet (""Vespa mandarinia"")—results from a considerably larger volume of venom being injected per sting. In addition to being the most venomous known wasp, ""Vespa luctuosa"" has one of the highest recorded toxicities of any known insect venom. Only harvester ant venom from the genus ""Pogonomyrmex"" (especially ""Pogonomyrmex maricopa""), as well as the unrelated ant ""Ectatomma tuberculatum"", are"
"species of rattlesnakes (11) than anywhere else in the world. The most common species is the extremely venomous Mojave rattler, which is considered the world's most dangerous rattlesnake. The largest rattle snake species here is the Western diamondback rattlesnake, while other species include the Black-tailed rattlesnake, Tiger rattler and Sidewinder rattler. Palm Springs is home to Tarantulas and various Scorpion species, including the Vinegaroon. Although Black bears are not common in the Coachella Valley, bears have been observed in Palm Springs and other parts of California. Today, Jaguars roam the northern Mexican dry-lands, however, they were previously common throughout the"
"Bothrops asper Bothrops asper is a highly venomous pit viper species ranging from southern Mexico to northern South America and is considered to be one of the most dangerous snakes in the western hemisphere. Sometimes referred to as the ""ultimate pit viper"", these snakes are found in a wide range of lowland habitats, often near human habitations. Its proximity to human habitations and temperament are likely the reasons why it is considered more dangerous to humans than others. This species is the main cause of snakebite incidents within its range. No subspecies are currently recognized. The generic name, ""Bothrops"", comes"
"Dyeing dart frog The dyeing dart frog, tinc (a nickname given by those in the hobby of keeping dart frogs), or dyeing poison frog (""Dendrobates tinctorius"") is a species of poison dart frog. It is among the largest species, reaching lengths of . This species is distributed throughout the eastern portion of the Guiana Shield and Venezuela, including parts of Guyana, Suriname, Brazil, and nearly all of French Guiana. Like most species of the genus ""Dendrobates"", ""D. tinctorius"" is highly toxic if consumed. It produces pumiliotoxins that the frog uses for self-defense. While pumiliotoxins are weaker than their derivative allopumiliotoxins"
"discovered with toxins in the skin. The same toxin had previously only been found in Colombian poison dart frogs from the genus ""Phyllobates"" (family Dendrobatidae). The batrachotoxin family of compounds are the most toxic compounds by weight in nature, being 250 times more toxic than strychnine. Later research found that the hooded pitohui had other batrachotoxins in its skin, including batrachotoxinin-A ""cis""-crotonate, batrachotoxinin-A and batrachotoxinin-A 3′-hydroxypentanoate. Bioassays of their tissue found that the skins and feathers were the most toxic, the heart and liver less toxic, and the skeletal muscles the least toxic parts of the birds. Of the feathers"
"likely candidate for the true identity of this spider is the dangerous Brazilian wandering spider ""Phoneutria fera"", of the family Ctenidae, as it is sometimes found hiding in clusters of bananas and is one of several spiders called the ""banana spider."" It is not technically a tarantula, but it is fairly large (4– to 5-inch legspan), somewhat hairy, and is highly venomous to humans. Another dangerous type of spider that has been confused with tarantulas is the Australasian funnel-web spider. The best known of these is the Sydney funnel-web spider ""Atrax robustus"", a spider that is aggressive, highly venomous, and"
"King cobra The king cobra (""Ophiophagus hannah""), also known as the hamadryad, is a venomous snake species in the family Elapidae, endemic to forests from India through Southeast Asia. It is threatened by habitat destruction and has been listed as Vulnerable on the IUCN Red List since 2010. It is the world's longest venomous snake. Adult king cobras are long. The longest known individual measured . Despite the word ""cobra"" in its common name, this species does not belong to genus ""Naja"" but is the sole member of its own. It preys chiefly on other snakes and occasionally on some"
"Yellow-banded poison dart frog The yellow-banded poison dart frog (""Dendrobates leucomelas""), also known as yellow-headed poison dart frog or bumblebee poison frog, is a poisonous frog from the genus ""Dendrobates"" of the family Dendrobatidae. ""Dendrobates leucomelas"" is found in the northern part of continent of South America, most notably in Venezuela. It is also found in parts of Guyana, Brazil, and the extreme easternmost part of Colombia. This amphibian is normally found in very humid conditions in tropical rain forests, close to fresh water. It is often found on flat rocks, trees, plants (notably bromeliads), and the leaf litter of"
"as being of ""least concern"". The main threats it faces are logging, habitat destruction, wildfire and collection of animals to be sold as pets on an international market. There are some conservation areas within its range. Brazil-nut poison frog The Brazil-nut poison frog (Adelphobates castaneoticus) is a species of frog in the family Dendrobatidae. It is endemic to the state of Pará in Brazil. The frog is believed to have received its common name from the fact that its tadpoles sometimes develop in the hard capsules of the Brazil nut tree, which are common in its range. The nuts fall"
"Guyana, Suriname, French Guiana, Brazil, and northern Bolivia. The type locality given is ""Tomé Assú, Acará Mirim River, State of Pará, Brazil"". ""B. brazili"" is an uncommon species, and bites from it have not yet been recorded. However, it is greatly feared by the indigenous people of southeastern Colombia. As variations in scalation and color pattern are apparent in different populations of ""B. brazili"", new taxa will likely be defined as a result of further research. Bothrops brazili Bothrops brazili (Brazil's lancehead) is a venomous pitviper species endemic to South America. No subspecies are currently recognized. The specific name, ""brazili"","