Gilbert's Skink
Encyclopedia
Gilbert's Skink is a heavy-bodied medium-sized lizard
of the family of skink
s living in the south-western United States
. It grows to about 7 to 12 cm (2.75 to 4.75 inches) total length.
in 1896. It was named in honor of Van Denburgh's teacher, Dr. Charles H. Gilbert (1859 - 1928), who at the time was a professor of zoology
at Stanford University
.
There are five subspecies
of Plestiodon gilberti:
(P.g. placerensis got its name from Placer County, California
, where it occurs.)
Together with the Western Skink
(E. skiltonianus), the San Lucan Skink
(E. lagunensis), and the Four-lined Asiatic Skink (P. quadrilineatus), the Western Skink belongs to the so-called "skiltonianus group". The exact taxonomy within this group is being questioned and may need revision following DNA
analysis research.
. It is found in the northern San Joaquin Valley
, in the foothills of the Sierra Nevada from Butte County
southward, and along the inner flanks of the Coast Ranges from San Francisco Bay
to the Mexican border and into northern Baja California
. It is also found in the mountains of southern California, and at scattered mountain localities in the eastern desert from Mono County
to San Bernardino County
. Isolated populations also occur in western Arizona
as well as in southern Nevada
.
Gilbert's Skink occurs in habitat ranging from sea level to elevations of about 2200 m (7300 ft). Found in a wide variety of habitats, this lizard is commonest in early successional stages or open areas within habitats in which it occurs, which ranges from grassland to open chaparral
or open pine forests. Heavy brush and densely forested areas are generally avoided.
Gilbert's Skink is a heavy-bodied lizard with small legs. Adults are uniformly colored in green, grey, olive or brown. Juveniles have light stripes on the sides and the back enclosing a broad black or brown stripe. This dark stripe stops near base of a waxy-pink tail. The striping fades with growth and maturation.
This robust skink is seldom seen in the open. It forages through leaf litter and dense vegetation, occasionally digging through loose soil. It is a good burrower and often constructs its own shelter by burrowing under surface objects such as rocks or rotting logs. Females construct nest chambers in loose moist soil several centimeters deep, especially under flat stones.
The reproductive season for this species varies geographically and from year to year depending on local conditions. Little is known about the timing of reproduction, but it is probably similar to the Western Skink
. Clutch size varies from 3 to 9 eggs.
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...
of the family of skink
Skink
Skinks are lizards belonging to the family Scincidae. Together with several other lizard families, including Lacertidae , they comprise the superfamily or infraorder Scincomorpha...
s living in the south-western United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. It grows to about 7 to 12 cm (2.75 to 4.75 inches) total length.
Taxonomy
Plestiodon gilberti was first described by Van DenburghJohn Van Denburgh
John Van Denburgh was a U.S. herpetologist from California.He was born in San Francisco and enrolled at Stanford University in 1891. As of 1895, he organized the herpetology department of the California Academy of Sciences. In 1897 he got a Ph.D. from Stanford University. Additionally, he got an M.D...
in 1896. It was named in honor of Van Denburgh's teacher, Dr. Charles H. Gilbert (1859 - 1928), who at the time was a professor of zoology
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
at Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
.
There are five subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of Plestiodon gilberti:
- Arizona Skink (P. g. arizonensis); LoweCharles Herbert LoweCharles Herbert Lowe, Jr was a U.S. biologist and herpetologist.Lowe was born in Los Angeles, California. After college he served during World War II as a U.S. Navy Ensign in the Pacific. In 1946, he enrolled at UCLA, where he received a Ph.D. in 1950...
and ShannonFrederick A. ShannonFrederick A. Shannon was a U.S. herpetologist and medical doctor.-Biography:He was born in Mount Pleasant, Iowa, the son of Fred Albert Shannon and Edna M. Shannon....
, 1954 - Greater Brown Skink (P. g. gilberti); Van Denburgh, 1896
- Northern Brown Skink (P. g. placerensis); Rodgers, 1944
- Variegated Skink (P. g. cancellosus); Rodgers and FitchHenry Sheldon FitchHenry Sheldon Fitch was an American herpetologist.Fitch was born in Utica, New York. When he was a year old, the family moved to Medford in the Rogue Valley in Oregon. Growing up, he had a keen interest in all the reptiles he could find on his father's 116 acre ranch...
, 1947 - Western Red-tailed Skink (P. g. rubricaudatus); TaylorEdward Harrison TaylorEdward Harrison Taylor was an American herpetologist from Kansas.He was born in Maysville, Missouri and studied at the University of Kansas in Lawrence, Kansas, graduating with a B.A. in 1912. Subsequently, he went to the Philippines, where at first he held a teacher's post in a village in central...
, 1935
(P.g. placerensis got its name from Placer County, California
Placer County, California
Placer County is a county located in both the Sacramento Valley and Sierra Nevada regions of the U.S. state of California, in what is known as the Gold Country. It stretches from the suburbs of Sacramento to Lake Tahoe and the Nevada border. Because of the expansion of the Greater Sacramento,...
, where it occurs.)
Together with the Western Skink
Western Skink
The Western Skink is a small, smooth-scaled lizard with relatively small limbs, measuring about 100 to 200 mm long. It is one of five species of lizards in Canada. Western skinks are very adaptable. They spend much of their day basking in the sun. Their diet ranges widely, including spiders...
(E. skiltonianus), the San Lucan Skink
San Lucan Skink
The San Lucan Skink, Eumeces lagunensis, is a skink native to the Baja California peninsula.Together with the Western Skink , Gilbert's Skink , and the Four-lined Asiatic Skink , the San Lucan Skink belongs to the so-called "skiltonianus group"...
(E. lagunensis), and the Four-lined Asiatic Skink (P. quadrilineatus), the Western Skink belongs to the so-called "skiltonianus group". The exact taxonomy within this group is being questioned and may need revision following DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
analysis research.
Range and habitat
Gilbert's Skink occurs mainly in CaliforniaCalifornia
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...
. It is found in the northern San Joaquin Valley
San Joaquin Valley
The San Joaquin Valley is the area of the Central Valley of California that lies south of the Sacramento – San Joaquin River Delta in Stockton...
, in the foothills of the Sierra Nevada from Butte County
Butte County, California
Butte County is a county located in the Central Valley of the US state of California, north of the state capital of Sacramento. As of the 2010 census, it had a population of 220,000. The county seat is Oroville. Butte County is the "Land of Natural Wealth and Beauty."Butte County is watered by the...
southward, and along the inner flanks of the Coast Ranges from San Francisco Bay
San Francisco Bay
San Francisco Bay is a shallow, productive estuary through which water draining from approximately forty percent of California, flowing in the Sacramento and San Joaquin rivers from the Sierra Nevada mountains, enters the Pacific Ocean...
to the Mexican border and into northern 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...
. It is also found in the mountains of southern California, and at scattered mountain localities in the eastern desert from Mono County
Mono County, California
Mono County is a county located in the east central portion of the U.S. state of California, to the east of the Sierra Nevada between Yosemite National Park and Nevada. As of the 2010 census, the population was 14,202, up from 12,853 at the 2000 census...
to San Bernardino County
San Bernardino County, California
San Bernardino County is a county in the U.S. state of California. As of the 2010 census, the population was 2,035,210, up from 1,709,434 as of the 2000 census...
. Isolated populations also occur in western Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
as well as in southern 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...
.
Gilbert's Skink occurs in habitat ranging from sea level to elevations of about 2200 m (7300 ft). Found in a wide variety of habitats, this lizard is commonest in early successional stages or open areas within habitats in which it occurs, which ranges from grassland to open chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
or open pine forests. Heavy brush and densely forested areas are generally avoided.
Description
This robust skink is seldom seen in the open. It forages through leaf litter and dense vegetation, occasionally digging through loose soil. It is a good burrower and often constructs its own shelter by burrowing under surface objects such as rocks or rotting logs. Females construct nest chambers in loose moist soil several centimeters deep, especially under flat stones.
The reproductive season for this species varies geographically and from year to year depending on local conditions. Little is known about the timing of reproduction, but it is probably similar to the Western Skink
Western Skink
The Western Skink is a small, smooth-scaled lizard with relatively small limbs, measuring about 100 to 200 mm long. It is one of five species of lizards in Canada. Western skinks are very adaptable. They spend much of their day basking in the sun. Their diet ranges widely, including spiders...
. Clutch size varies from 3 to 9 eggs.
External links
- Gilbert's Skink at the U.S. Geological Survey.
- Gilbert's Skink at the California Department of Fish and Game.