''Hypsiglena'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of small, rear-fanged,

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 ev ...

snake Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more j ...

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 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 subspecies are recognized as being valid. *''

Hypsiglena affinis ''Hypsiglena'' is a genus of small, rear-fanged, Colubridae, 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 ...

'' Boulenger, 1894 - Boulenger's night snake *'' Hypsiglena catalinae'' W.W. Tanner, 1966 - Santa Catalina night snake *'' Hypsiglena chlorophaea''

Cope The cope (known in Latin as ''pluviale'' 'rain coat' or ''cappa'' 'cape') is a liturgical vestment, more precisely a long mantle or cloak, open in front and fastened at the breast with a band or clasp. It may be of any liturgical colour. A c ...

, 1860 - Sonoran night snake **'' Hypsiglena chlorophaea deserticola'' W.W. Tanner, 1966 - desert night snake **'' Hypsiglena chlorophaea loreala'' W.W. Tanner, 1944 -

Mesa Verde Mesa Verde National Park is an American national park and UNESCO World Heritage Site located in Montezuma County, Colorado. The park protects some of the best-preserved Ancestral Puebloan archaeological sites in the United States. Established ...

night snake **'' Hypsiglena chlorophaea tiburonensis'' 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 night snake **'' Hypsiglena jani texana'' Stejneger, 1893 -

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

night snake **'' Hypsiglena jani dunklei''

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) Pl ...

, 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'' Cope, 1860 - spotted night snake **'' Hypsiglena ochrorhynchus baueri'' Zweifel, 1958 -

Cedros Island Cedros Island (''Isla de Cedros'', "island of cedars" in Spanish) is an island in the Pacific Ocean belonging to the state of Baja California, Mexico. The dry and rocky island had a population of 1,350 in 2005 and has an area of which include ...

night snake **'' Hypsiglena ochrorhynchus gularis'' W.W. Tanner, 1954 - Isla Partida 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 eighth most populous city in the United State ...

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 ...

1962 - San Martín Island night snake **'' Hypsiglena ochrorhynchus nuchalata'' W.W. Tanner, 1943 - California night snake **'' Hypsiglena ochrorhynchus tortugaensis'' W.W. Tanner, 1944 - Isla Tortuga night snake **'' Hypsiglena ochrorhynchus venusta'' 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 & Lieb, 1972 - Tanzer's night snake *''

Hypsiglena torquata The night snake (''Hypsiglena torquata'') is a species of rear-fanged colubrid. It is found from British Columbia, Canada through the western United States to Mexico. Subspecies previously recognized within ''H. torquata'' *'' Hypsiglena torqu ...

'' ( Günther, 1860) - Sinaloa 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 territori ...

, 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 th ...

, west to

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

, 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 o ...

, 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 regions with rocky and sandy

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

Description

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

pupil The pupil is a black hole located in the center of the Iris (anatomy), iris of the Human eye, eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing ...

s. 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 us ...

, 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 ...

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

Behavior

''Hypsiglena'' are nocturnal and

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

Diet

The diet of night snakes consists primarily of lizards, but they will also consume smaller

s, and amphibians.

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 st ...

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