Bothrops moojeni
Silhouette: Steven Traver · PhyloPic
In 3 days ~50% in a week ~80%
Bothrops moojeni, commonly known in English as the Brazilian lancehead, is a species of highly venomous snake in the family Viperidae. It is a pit viper endemic to South America. The specific name, moojeni, is in honor of Brazilian zoologist João Moojen de Oliveira (1904–1985).
Bothrops moojeni grows to an average total length (tail included) of 1.6 m (5.2 ft), with a maximum of 2.3 m (7.5 ft) already reported. It has a tan, gray-brown or olive-gray color, with 14–21 trapezoidal side markings that are dark gray or completely black. There are 23–29 rows of dorsal scales on the body. The belly is usually white or cream, with scattered dark gray spots. Juveniles have a white tail. The species is terrestrial and nocturnal.
It is considered very defensive. Its body varies from medium to heavy. The broad head is flattened in a lance shape when seen from above, and is distinct from the narrow neck. The snout is not elevated. The eyes are medium in size, with vertically elliptical pupils. The dorsal scales are keeled. B. moojeni is viviparous. Gestation lasts around four months, occurs once a year, and litter size is usually 12–14 neonates. B.... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Emas National Park | 🇧🇷 Brazil | |
| 2 | Iguazú National Park | 🇦🇷 Argentina | |
| 3 | Iguaçu National Park | 🇧🇷 Brazil |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Zoo Miami | 🇺🇸 United States | |
| 2 | Zoológico de Brasília | 🇧🇷 Brazil | |
| 3 | São Paulo Zoo | 🇧🇷 Brazil | |
| 4 | Zoológico de Goiânia | 🇧🇷 Brazil | |
| 5 | Houston Zoo | 🇺🇸 United States | |
| 6 | Philadelphia Zoo | 🇺🇸 United States | |
| 7 | Municipal Zoological Park Quinzinho de Barros | 🇧🇷 Brazil | |
| 8 | Rio de Janeiro Zoological Garden | 🇧🇷 Brazil | |
| 9 | Parque Ecológico de São Carlos | 🇧🇷 Brazil | |
| 10 | Reptile Gardens | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report a Brazilian Lancehead sighting in Iguazú National Park on a given day, based on 24 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 8th most-seen of the 18 reptiles we can rate there. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
January–February and August
In those months about 30% of wildlife watchers report a Brazilian Lancehead in Iguazú National Park on a given day, against under 5% in May and June, the lowest months.
Between 6 and 9 pm
Across all the parks we cover, that three-hour window holds the most Brazilian Lancehead sightings with a recorded time, and about 6 in 10 of them come between 6 am and 6 pm: it is seen both by day and at night.
2nd of 3
Of the 3 parks where we can rate Brazilian Lancehead sightings, Iguazú National Park ranks 2nd at about 20%. The best odds are in Emas National Park (Brazil, about 30%).
Same genus: Bothrops
The closest relatives of the Brazilian Lancehead that you can see in Iguazú National Park (genus Bothrops, Neotropical Lanceheads) are Jararacussu (about 10%) and Painted Lancehead (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brazilian Lancehead is recorded against all the reptiles logged in Iguazú National Park (24 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
