Sauromalus ater
Encyclopedia
The Common Chuckwalla is a species of lizard
in the family Iguanidae
. It inhabits the Sonoran
and Mojave Desert
s of the southwestern United States
and northwestern Mexico
. Its range extends from Eastern California
, Utah
, and Nevada
south to Baja California
and Sonora
.
word "tcaxxwal" or "caxwal," the form used by the Cahuilla
of southeastern California.
Its generic
name, sauromalus, is a combination of two Ancient Greek
words:σαῦρος (sauros) meaning "lizard". and ομαλυς (omalus) meaning "flat". Its specific
name is ater, Latin
for "black" or "dark"
Its original epithet
was Sauromalus obesus; and although that name is no longer officially recognized, it is still very common in the literature and it remains in many standard natural history
references for North America. In 1998, Bradford D. Hollingsworth examined variations in Sauromalus and concluded that only five species should be recognized. He regarded S. obesus as conspecific with S. ater, and he used S. ater, which has priority, as the specific name of the combined taxon. No subspecies of S. ater are currently recognized. Based primarily on the extensive use of the name S. obesus, a petition to give that name precedence over that of S. ater was submitted to the ICZN
. However this reasoning was dubious and the priority of S. ater was maintained. In 2004, ICZN ruled that the name Sauromalus ater was first described by zoologist Auguste Duméril
in 1856 and thus had precedence over the name Sauromalus obesus which was not named until 1858 by Baird.
Males are seasonally and conditionally territorial; an abundance of resources tends to create a hierarchy based on size, with one large male dominating the area's smaller males. Chuckwallas use a combination of colour and physical displays, namely "push ups", head-hobbing, and gaping of the mouth to communicate and defend their territory (see animal communication
).
Chuckwallas are diurnal
animals and as they are exothermic
, spend much of their mornings and winter days basking. These lizards are well adapted to desert conditions; they are active at temperatures of up to 102°F (39°C). Chuckwallas brumate during cooler months and emerge in February.
Mating occurs from April to July, with 5-16 eggs laid between June and August. The eggs hatch in late September.
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
in the family Iguanidae
Iguanidae
Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...
. It inhabits the Sonoran
Sonoran Desert
The Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...
and Mojave Desert
Mojave Desert
The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...
s of the southwestern United States
Southwestern United States
The Southwestern United States is a region defined in different ways by different sources. Broad definitions include nearly a quarter of the United States, including Arizona, California, Colorado, Nevada, New Mexico, Oklahoma, Texas and Utah...
and northwestern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. Its range extends from Eastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, and Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
south to Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
and Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
.
Taxonomy
The common name "chuckwalla" (or chuckawalla) is derived from the ShoshoneShoshone
The Shoshone or Shoshoni are a Native American tribe in the United States with three large divisions: the Northern, the Western and the Eastern....
word "tcaxxwal" or "caxwal," the form used by the Cahuilla
Cahuilla
The Cahuilla, Iviatim in their own language, are Indians with a common culture whose ancestors inhabited inland areas of southern California 2,000 years ago. Their original territory included an area of about . The traditional Cahuilla territory was near the geographic center of Southern California...
of southeastern California.
Its generic
Genera
Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...
name, sauromalus, is a combination of two Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
words:σαῦρος (sauros) meaning "lizard". and ομαλυς (omalus) meaning "flat". Its specific
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
name is ater, Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "black" or "dark"
Its original epithet
Epithet
An epithet or byname is a descriptive term accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, divinities, objects, and binomial nomenclature. It is also a descriptive title...
was Sauromalus obesus; and although that name is no longer officially recognized, it is still very common in the literature and it remains in many standard natural history
Natural history
Natural history is the scientific research of plants or animals, leaning more towards observational rather than experimental methods of study, and encompasses more research published in magazines than in academic journals. Grouped among the natural sciences, natural history is the systematic study...
references for North America. In 1998, Bradford D. Hollingsworth examined variations in Sauromalus and concluded that only five species should be recognized. He regarded S. obesus as conspecific with S. ater, and he used S. ater, which has priority, as the specific name of the combined taxon. No subspecies of S. ater are currently recognized. Based primarily on the extensive use of the name S. obesus, a petition to give that name precedence over that of S. ater was submitted to the ICZN
International Commission on Zoological Nomenclature
The International Commission on Zoological Nomenclature is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 28 members from 20 countries, mainly practicing zoological taxonomists...
. However this reasoning was dubious and the priority of S. ater was maintained. In 2004, ICZN ruled that the name Sauromalus ater was first described by zoologist Auguste Duméril
Auguste Duméril
Auguste Henri André Duméril was a French zoologist. He was professor of Herpetology and Ichthyology at the Muséum National d'Histoire Naturelle in Paris from 1857. His father André Marie Constant Duméril was also a zoologist...
in 1856 and thus had precedence over the name Sauromalus obesus which was not named until 1858 by Baird.
Description
The common chuckwalla is a large, flat-bodied lizard with a large rounded belly, and a wide-based blunt-tipped tail. Reaching a total length of 40 centimetres (15.7 in) and a weight of 0.9 kilograms (2 lb). Small scales cover its body, with larger scales protecting the ear openings. The coloration of these lizards varies by location and between juveniles and adults, as well as among males and females. In adult males, the head, shoulder, and pelvic regions are black while the mid-body is light tan speckled with brown. Adult females are brownish in color with a scattering of dark red spots. Young chuckwallas have four or five broad bands across the body, and three or four on the tail which are lost in adulthood by males, but retained somewhat by females.Behavior
Harmless to humans, these lizards are known to run from potential threats. When disturbed, the Chuckwalla will gulp air, distend its body and wedge itself into a tight rock crevice. The Chuckwalla will inflate its body with air in order to entrench itself.Males are seasonally and conditionally territorial; an abundance of resources tends to create a hierarchy based on size, with one large male dominating the area's smaller males. Chuckwallas use a combination of colour and physical displays, namely "push ups", head-hobbing, and gaping of the mouth to communicate and defend their territory (see animal communication
Animal communication
Animal communication is any behavior on the part of one animal that has an effect on the current or future behaviour of another animal. The study of animal communication, is sometimes called Zoosemiotics has played an important part in the...
).
Chuckwallas are diurnal
Diurnal animal
Diurnality is a plant or animal behavior characterized by activity during the day and sleeping at night.-In animals:Animals that are not diurnal might be nocturnal or crepuscular . Many animal species are diurnal, including many mammals, insects, reptiles and birds...
animals and as they are exothermic
Exothermic
In thermodynamics, the term exothermic describes a process or reaction that releases energy from the system, usually in the form of heat, but also in the form of light , electricity , or sound...
, spend much of their mornings and winter days basking. These lizards are well adapted to desert conditions; they are active at temperatures of up to 102°F (39°C). Chuckwallas brumate during cooler months and emerge in February.
Mating occurs from April to July, with 5-16 eggs laid between June and August. The eggs hatch in late September.