''Crotalus aquilus'', known as the Querétaro dusky rattlesnake . or Queretaran dusky rattlesnake, is a pit viper

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

found in the highlands of central

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. Like all other pit vipers, it is

venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

. No subspecies are currently recognized. The specific name, ''aquilus'', is

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

for "eagle" and refers to the high altitude at which this

is found.

Description

This species grows to a maximum reported total length of , but most adult specimens, which have been described as heavy-bodied, are less than long.

Geographic range

They are found in the highlands of central Mexico in Guanajuato,

Hidalgo Hidalgo may refer to: People * Hidalgo (nobility), members of the Spanish nobility * Hidalgo (surname) Places Mexico * Hidalgo (state), in central Mexico * Hidalgo, Coahuila, a town in the north Mexican state of Coahuila * Hidalgo, Nuevo Le� ...

México Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatem ...

, Michoacán, and San Luis Potosí. The type locality given is "near Alvarez, San Luis Potosí, Mexico".

Habitat

These snakes are found in the open grassy and generally rocky habitats north of the

Trans-Mexican Volcanic Belt The Trans-Mexican Volcanic Belt ( es, Eje Volcánico Transversal), also known as the Transvolcanic Belt and locally as the (''Snowy Mountain Range''), is an active volcanic belt that covers central-southern Mexico. Several of its highest peaks h ...

. They also occur in pine-oak forest, open karstic areas, grassy mountain meadows, and stony mesquite-grassland.

Conservation status

This species is classified as Least Concern on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

(v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was down when assessed in 2007.

Description

Geographic range

Habitat

Conservation status

References

Further reading