''Hypsiglena'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of small,

rear-fanged A snake skeleton consists primarily of the skull, vertebrae, and ribs, with only vestigial remnants of the limbs. Skull The skull of a snake is a very complex structure, with numerous joints to allow the snake to swallow prey far larger than i ...

colubrid Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest species of the family date back to the Oligocene epoch. Colubrid snakes are found on ever ...

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

s commonly referred to as night snakes. The genus consists of nine

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 ...

, and

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirre-León G, Cervantes-Pasqualli JA, Zug GR (2014). "Rediscovery of an endemic vertebrate from the remote Islas Revillagigedo in the eastern Pacific Ocean: The Clarión Nightsnake, with conservation and systematic implications". ''PLOS ONE'' 9 (5): e97682.

Species and subspecies

The following species and

are recognized as being valid. *''

Hypsiglena affinis ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirre ...

Boulenger Boulenger is a surname. Notable people with the surname include: * Benjamin Boulenger (born 1990), French footballer * Edward George Boulenger (1888–1946), British zoologist, director of aquarium at London Zoo * George Albert Boulenger (1858–1 ...

, 1894 - Boulenger's night snake *''

Hypsiglena catalinae ''Hypsiglena catalinae'', the Isla Santa Catalina night snake, is a species of snake in the family Colubridae. The species is native to Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern ...

'' W.W. Tanner, 1966 - Santa Catalina night snake *''

Hypsiglena chlorophaea ''Hypsiglena chlorophaea'', the desert night snake, is a species of snake in the family Colubridae. The species is native to Mexico, Canada, and the United States The United States of America (U.S.A. or USA), commonly known as the Unite ...

'' Cope, 1860 -

Sonora Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...

n night snake **''

Hypsiglena chlorophaea deserticola ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirre ...

'' W.W. Tanner, 1966 - desert night snake **''

Hypsiglena chlorophaea loreala ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirr ...

'' W.W. Tanner, 1944 - Mesa Verde night snake **''

Hypsiglena chlorophaea tiburonensis ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirr ...

'' W.W. Tanner, 1981 -

Tiburón Island Tiburón Island is the largest island in the Gulf of California and the largest island in Mexico, with an area of . It was made a nature reserve in 1963 by President Adolfo López Mateos. Etymology is Spanish for 'shark'. Although the Seri nam ...

night snake *''

Hypsiglena jani ''Hypsiglena jani'', commonly known as the Texas night snake or the Chihuahuan night snake, is a small species of mildly venomous snake in the family Colubridae. The species is native to the southwestern United States and adjacent northeastern ...

'' ( Dugès, 1865) -

Chihuahua Chihuahua may refer to: Places *Chihuahua (state), a Mexican state **Chihuahua (dog), a breed of dog named after the state **Chihuahua cheese, a type of cheese originating in the state **Chihuahua City, the capital city of the state **Chihuahua Mun ...

night snake **''

Hypsiglena jani texana ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirr ...

Stejneger Leonhard Hess Stejneger (30 October 1851 – 28 February 1943) was a Norwegian-born American ornithologist, herpetologist and zoologist. Stejneger specialized in vertebrate natural history studies. He gained his greatest reputation with reptiles ...

, 1893 -

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

night snake **''

Hypsiglena jani dunklei ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirr ...

Taylor Taylor, Taylors or Taylor's may refer to: People * Taylor (surname) **List of people with surname Taylor * Taylor (given name), including Tayla and Taylah * Taylor sept, a branch of Scottish clan Cameron * Justice Taylor (disambiguation) Plac ...

, 1938 -

Tamaulipas Tamaulipas (), officially the Free and Sovereign State of Tamaulipas ( es, Estado Libre y Soberano de Tamaulipas), is a state in the northeast region of Mexico; one of the 31 states which, along with Mexico City, comprise the 32 Federal Entiti ...

night snake *''

Hypsiglena ochrorhynchus ''Hypsiglena ochrorhynchus'', also known commonly as the coast night snake and the spotted night snake, is a species of snake in the subfamily Dipsadinae of the family Colubridae. The species is native to California in the United States and to ...

'' Cope, 1860 - spotted night snake **'' Hypsiglena ochrorhynchus baueri'' Zweifel, 1958 - Cedros Island night snake **'' Hypsiglena ochrorhynchus gularis'' W.W. Tanner, 1954 -

Isla Partida Isla Partida is separated from Isla Espíritu Santo by a shallow, narrow channel. These two islands, in the Gulf of California, are protected by UNESCO as biospheres. They are located a short boat ride from La Paz, which lies on the Baja Califo ...

night snake **'' Hypsiglena ochrorhynchus klauberi'' W.W. Tanner, 1944 -

San Diego San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...

night snake **'' Hypsiglena ochrorhynchus martinensis'' W.W. Tanner &

Banta Banta Soda, or Banta, also Goli Soda or Goti Soda and Fotash Jawl, is a popular carbonated lemon or orange-flavoured soft drink sold in India since the late 19th century in a distinctly shaped iconic Codd-neck bottle. The pressure created by t ...

1962 - San Martín Island night snake **'' Hypsiglena ochrorhynchus nuchalata'' W.W. Tanner, 1943 -

California night snake The California night snake (''Hypsiglena ochrorhynchus nuchalata'') is a subspecies of small colubrid snake native to California.ITIS (Integrated Taxonomic Information System). www.itis.gov. Description The California night snake grows to a tot ...

**'' Hypsiglena ochrorhynchus tortugaensis'' W.W. Tanner, 1944 - Isla Tortuga night snake **''

Hypsiglena ochrorhynchus venusta ''Hypsiglena'' is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of nine species, and subspecies have been maintained pending further investigation.Mulcahy DG, Martínez-Gómez JE, Aguirre ...

'' Mocquard, 1899 - Central Baja night snake *'' Hypsiglena slevini'' W.W.Tanner, 1943 -

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

night snake *'' Hypsiglena tanzeri''

Dixon Dixon may refer to: Places International * Dixon Entrance, part of the Inside Passage between Alaska and British Columbia Canada * Dixon, Ontario United States * Dixon, California * Dixon, Illinois * Dixon, Greene County, Indiana * Dixon, Indi ...

& Lieb, 1972 - Tanzer's night snake *'' Hypsiglena torquata'' ( Günther, 1860) -

Sinaloa Sinaloa (), officially the Estado Libre y Soberano de Sinaloa ( en, Free and Sovereign State of Sinaloa), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. It is d ...

night snake *'' Hypsiglena unaocularus'' W.W.Tanner, 1946 - Islas Revillagigedo night snake ''

Nota bene (, or ; plural form ) is a Latin phrase meaning "note well". It is often abbreviated as NB, n.b., or with the ligature and first appeared in English writing . In Modern English, it is used, particularly in legal papers, to draw the atten ...

'': A

binomial authority In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

or trinomial authority in parentheses indicates that the species or subspecies was originally described in a genus other than ''Hypsiglena''.

Geographic range

''Hypsiglena'' are found throughout the southwestern and western

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, from

and

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...

, west to

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, north to

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered on ...

, and south into

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 ...

, as well as on islands off the coasts of Mexico.

Habitat

The preferred habitat of night snakes is semiarid

desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...

regions with rocky and sandy

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

Description

Night snakes typically do not exceed a total length (including tail) of . They are slender-bodied with a flattened head, and have small

eye Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and conv ...

s with vertical pupils. Their color varies depending on their locality, often matching the soil color of their native habitat. They occur in various shades of

gray Grey (more common in British English) or gray (more common in American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is "without color", because it can be composed o ...

, and

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model used ...

, with dark brown, gray or

black Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have o ...

blotches on the back and the sides. Many also have distinctive black markings on the neck region.

Behavior

''Hypsiglena'' are

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

and terrestrial.

Diet

The diet of night snakes consists primarily of

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

s, but they will also consume smaller

s, and

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

Venom

The

venom 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 ...

of ''Hypsiglena'' is not considered to be dangerous to humans.

References

External links

* {{Taxonbar, from=Q3022965 Colubrids Vertebrates of Mexico Reptiles of the United States Snake genera Taxa named by Edward Drinker Cope