The Trans-Pecos rat snake or Davis Mountain rat snake (''Bogertophis subocularis''), is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of medium to large, nonvenomous rat snake in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Colubridae Colubridae (, commonly known as colubrids , from , 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest fossil species of the family date back to the Late Eocene epoch, with earlier origins suspected. C ...

. ''Bogertophis subocularis'' is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the Chihuahuan Desert.

Geographic range

The Trans-Pecos rat snake is found in the Mexican states of Chihuahua,

Coahuila Coahuila, formally Coahuila de Zaragoza, officially the Free and Sovereign State of Coahuila de Zaragoza, is one of the 31 states of Mexico. The largest city and State Capital is the city of Saltillo; the second largest is Torreón and the thi ...

Durango Durango, officially the Free and Sovereign State of Durango, is one of the 31 states which make up the Political divisions of Mexico, 32 Federal Entities of Mexico, situated in the northwest portion of the country. With a population of 1,832,650 ...

, and

Nuevo León Nuevo León, officially the Free and Sovereign State of Nuevo León, is a Administrative divisions of Mexico, state in northeastern Mexico. The state borders the Mexican states of Tamaulipas, Coahuila, Zacatecas, and San Luis Potosí, San Luis ...

, and its range extends northward into

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

and

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. Wright, Albert Hazen; Wright, Anna Allen (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock. 1,105 pp. (in two volumes). (''Elaphe subocularis'', pp. 255-259, Figure 79 + Map 23 on p. 223).

Description

''B. subocularis'' has a row of small scales ( suboculars) between the lower border of the eye and the upper labials. Schmidt KP, Davis DD (1941). ''Field Book of Snakes of the United States and Canada''. New York: G.P. Putnam's Sons. 365 pp. (''Elaphe subocularis'', pp. 152-153, Figure 41). Coloration is yellow to tan

dorsally Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

with a series of black, or dark brown, H-shaped markings. Conant R (1975). ''A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition''. Boston: Houghton Mifflin. xviii + 429 pp. + Plates 1-48. (hardcover), (paperback). (''Elaphe subocularis'', p. 197 + Plate 32 + Map 151). The eye is large and prominent, light-colored with a contrasting round black pupil. The tongue is pink. The

dorsal scales In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...

are in 31-35 rows at midbody. The ventrals number 260-277; the subcaudals number 69-79. Smith, Hobart M.; Brodie, Edmund D. Jr (1982). ''Reptiles of North America: A Guide to Field Identification''. New York: Golden Press. 240 pp. (hardcover), (paperback). (''Elaphe subocularis'', pp. 184-185). Adults are usually 36-54 inches (90–137 cm) in total length (including tail). The record total length is 66 inches (168 cm). Powell, Robert; Conant, Roger; Collins, Joseph T. (2016). ''Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition''. Boston and New York: Houghton Mifflin Harcourt. xsiv + 494 pp. . (''Bogertophis subocularis'', p. 384 + Plate 35). Trans-Pecos_rat_snake_Wildlife_World_Zoo

Trans-Pecos_rat_snake_Wildlife_World_Zoo

Habitat

The Trans-Pecos rat snake's

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

consists of

desert A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...

flats and brushy slopes, and rocky outcrops where it dens.

Diet

''B. subocularis'' feeds on small

vertebrates Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

Behavior

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

species, ''B. subocularis'' is uncommon and rarely seen in the wild, save on warm summer nights during the breeding season. Nicknamed "suboc" by enthusiasts, it is nonaggressive when approached, even passive, and is easily raised in captivity.

Sexual dimorphism

''B. subocularis'' exhibits

sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

. Females are larger than males as adults. Adult males reach between 3.5 and 4.5 feet (1.1-1.4 m) in total length (including tail); whereas females grow up to 5.5 feet (1.7 m).

Reproduction

The breeding season for ''B. subocularis'' runs through May and June, while

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the ...

-laying begins in July and ends by September. At nearly three months, their incubation period is lengthy for a snake, at the end of which a

clutch A clutch is a mechanical device that allows an output shaft to be disconnected from a rotating input shaft. The clutch's input shaft is typically attached to a motor, while the clutch's output shaft is connected to the mechanism that does th ...

of anywhere from three to 11 snakes, each in total length, hatch. As they are hatched during winter, the hatchlings may remain hidden underground for several months before venturing outside.

References

External links

Simply SubocsSuboc.com
{{Taxonbar, from=Q2697414 Bogertophis Fauna of the Chihuahuan Desert Reptiles of Mexico Reptiles of the United States Reptiles described in 1901