Crotalus triseriatus
Silhouette: Bill Bouton (source photo) & T. Michael Keesey (vectorization) · PhyloPic
In 3 days ~10% in a week ~20%
Common names: Mexican dusky rattlesnake, dusky rattlesnake Crotalus triseriatus is a venomous pit viper species found in Mexico. Two subspecies are currently recognized, including the nominate subspecies described here. Adult male specimens of C. triseriatus commonly grow to a total length (including tail) greater than 60 cm (24 in), with females somewhat smaller. The maximum recorded total length is 68.3 cm (26.9 in).
The species C. triseriatus is found in Mexico, along the southern edge of the Mexican Plateau in the highlands of the Transverse Volcanic Cordillera, including the states of Jalisco, México, Michoacán, Morelos, Nayarit, Puebla, Tlaxcala, and Veracruz. The type locality given by Wagler in 1830 is "Mexico". A restriction to "Alvarez, San Luis Potosí, Mexico" was proposed by H.M. Smith and Taylor (1950).
Crotalus triseriatus occurs in pine-oak forest, boreal forest, coniferous forest and, bunchgrass grasslands. On Volcán Orizaba, it is found at very high altitudes. There, the snow line comes down to about 4,572 m (15,000 ft), while green plants can be found up to 4,573 m (15,000 ft): the species has been found within... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Reserva de la Biosfera Mariposa Monarca | 🇲🇽 Mexico |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Toluca | 🇲🇽 México | |
| 2 | Mexico City | 🇲🇽 México |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | North Carolina Zoo | 🇺🇸 United States | |
| 2 | Saint Louis Zoo | 🇺🇸 United States | |
| 3 | San Antonio Zoo | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Dusky Rattlesnake sighting in Mexico City on a given day, based on 12 verified sightings from GBIF citizen-science data. It is the 33rd most-seen of the 37 reptiles we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
July
In that month about 10% of wildlife watchers report a Dusky Rattlesnake in Mexico City on a given day, against under 5% in August to June, the lowest months. That is one of Mexico City's wettest months, with about 150 mm of rain against 5 mm in December.
Between 6 and 9 pm
Across all the parks we cover, that three-hour window holds the most Dusky Rattlesnake sightings with a recorded time, and about 9 in 10 of them come between 6 pm and 6 am: it is mostly seen at night.
2nd of 2
Of the 2 cities where we can rate Dusky Rattlesnake sightings, Mexico City ranks 2nd at under 5%. The best odds are in Toluca (México, about 20%).
Same genus: Crotalus
The closest relatives of the Dusky Rattlesnake that you can see in Mexico City (genus Crotalus, Rattlesnakes) are Western Black-tailed Rattlesnake (about 10%) and Mexican Pygmy Rattlesnake (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Dusky Rattlesnake is recorded against all the reptiles logged in Mexico City (12 verified sightings), 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.
