Six-Lined Racerunner: Blue-Green-White Below, Green-Black-Brown Above

Summary: North American six-lined racerunner habitats get rough-scaled brown tails, green-black-brown bodies and smooth-scaled blue-green-white bellies and throats.

six-lined racerunner (Cnemidophorus sexlineatus); Guana Tolomato Matanzas National Estuarine Research Reserve (GTM NERR), northeastern Florida; Thursday, April 14, 2011, 20:26:56: Cindy Elder/GTM NERR (GTMResearchReserve), CC BY 2.0 Generic, via Flickr

North American six-lined racerunner habitats abound along Illinois-Iowa-Minnesota-Wisconsin borders, from Delaware through Florida, New Mexico, Wyoming, southern South Dakota, Missouri and Indiana, eastern Kentucky, southern West Virginia and Maryland and everywhere in-between.

Six-lined racerunners bear common names as back-striped eastern subspecies, prairie seven-lined subspecies westward and Texas yellow-headed subspecies and the scientific name Cnemidophorus sexlineatus (leg armor-bearing, six-lined). They carry Cnemidophorus sexlineatus sexlineatus, Cnemidophorus sexlineatus viridis (leg-armored, six-lined, green) and Cnemidophorus sexlineatus stephensae (Hazel J. Stephens Hickey, April 18, 1930-Aug. 17, 2009) subspecies names. Descriptions in 1766, 1966 and 1992 derive from Carl Linnaeus (May 23, 1707-Jan. 10, 1778), Charles Lowe, Jr. (April 16, 1920-Sept. 13, 2002) and Stanley Trauth.

Six-lined racerunner life cycles expect dry, open, sunny grasslands, sandy floodplains and woodlands with sunlit rocks for basking, thicket edges and well-drained soils for underground burrows.

April through June fit six-lined racerunner life cycles with related giant, plateau and Texas spotted, little striped, orange-throated and western whiptails' spring through summer breeding seasons.

Prairie seven-lined and six-lined racerunners grab the early morning sun's rays on ground-cover, rocks and soil until their body temperatures get to optimum ranges for foraging. They hasten into dense vegetation and underground burrows rather than have direct confrontations with competitors, enemies, intruders, predators and rivals while hunting for perches and prey. Identification of idle perches, of invertebrate prey and of invertebrate and vertebrate predators involves scent or taste by deep-forked, mobile tongues and sight by dark eyes.

Agro-industrialists, breeders, collectors, polluters and predatory crows, foxes, hedgehogs, mice, opossums, owls, raccoons, raptors, rats, shrews, skunks, snakes and weasels jeopardize North American six-lined racerunner habitats.

Prairie seven-lined and six-lined racerunners know brief courtships before internal fertilizations of calcium carbonate-shelled eggs that females keep laying in two seasonal 1- to 6-egg clutches.

Females lay the season's second clutch three weeks after the first laid in June and July, for 1- to 2-month incubations and June to September hatchings. Juveniles manifest light blue tails and measure about one-half snout-vent (excrementary opening) and total lengths of physically and sexually mature prairie seven-lined and six-lined racerunner adults. Crawling and low-, slow-flying, day-active, ground- to near-ground-level, opportunistic ants, beetles, centipedes, cockroaches, crickets, flies, gnats, grasshoppers, mosquitoes, moths, slugs, snails, spiders and termites nourish adults.

North American six-lined racerunner habitats offer season-coldest temperature ranges, north to southward, from minus 25 to 25 degrees Fahrenheit (minus 31.66 to minus 3.88 degrees Celsius).

Beach dunes, dry, hot, porous-soiled, open, sunny, well-drained fields, floodplains, grasslands, gravelly and sandy banks, hilly prairies, rocky outcroppings, sandhills, thickets and woodlands protect six-lined racerunners.

Six to 10.5 inches (15.24 to 26.67 centimeters) and 7.06 ounces (200 grams) queue up as physically and sexually mature six-lined racerunner total lengths and weights. Adults reveal blue-white or white abdomens with large, lengthwise-rowed, rectangular, smooth scales, green or green-black-brown bodies with grainy-, small-scaled backs and rough-scaled, side-striped, whorled brown tails. Females and males show respectively white and blue or green throats while prairie seven-lined and six-lined racerunners respectively sport bright green- or green-black-brown-banded backs and heads.

Blue-green-throated males and white-throated females team grainy-, small-scaled backs with brown, rough-scaled, whorled tails and large-, rectangular-, smooth-scaled blue-white abdomens in North American six-lined racerunner habitats.

dorsal (top) and ventral (bottom) views of six-lined racerunner (Cnemidophorus sexlineatus), under synonym of Ameiva sex-lineata; J. Sera, illustration; George Lehman/Lehman & Duval Lithographers; J.E. Holbrook's North American Herpetology (1836), vol. I, Plate VI, opposite page 63: Not in copyright, via Biodiversity Heritage Library

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

six-lined racerunner (Cnemidophorus sexlineatus); Guana Tolomato Matanzas National Estuarine Research Reserve (GTM NERR), northeastern Florida; Thursday, April 14, 2011, 20:26:56: Cindy Elder/GTM NERR (GTMResearchReserve), CC BY 2.0 Generic, via Flickr @ https://www.flickr.com/photos/gtmnerr/6638402499/

dorsal (top) and ventral (bottom) views of six-lined racerunner (Cnemidophorus sexlineatus), under synonym of Ameiva sex-lineata; J. Sera, illustration; George Lehman/Lehman & Duval Lithographers; J.E. Holbrook's North American Herpetology (1836), vol. I, Plate VI, opposite page 63: Not in copyright, via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/4075463' Biodiversity Heritage Library (BioDivLibrary), Public Domain, via Flickr @ https://www.flickr.com/photos/61021753@N02/7209597608/

For further information:

Grzimek's Animal Life Encyclopedia, 2nd edition. Volume 7, Reptiles, edited by Michael Hutchins, James B. Murphy, and Neil Schlager. Farmington Hills MI: Gale Group, 2003.

"Hazel. [sic] J Hickey of Jonesboro, Arkansas / 1930 - 2009 / Obituary." Emerson Funeral Home > Obituaries.
Available @ http://www.emersonfuneralhome.com/obituary/410643

Holbrook, John Edwards. 1836. "Ameiva sex-lineata. Plate VI." North American Herpetology; Or, A Description of the Reptiles Inhabiting the United States. Vol. I: 63-66. Philadelphia PA: J. Dobson.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/4075463

Linnaeus. 1766. "18. Lacerta 6-lineata." Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I: 364. Editio Duodecima, Reformata. Holmiae [Stockholm, Sweden]: Laurentii Salvii [Laurentius Salvius].
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/42946560

Lowe, Charles H. 1966. "The Prairie Lined Racerunner: Cnemidophorus sexlineatus viridis subsp. nov. Prairie Lined Racerunner." Journal of the Arizona Academy of Science, vol. 4, no. 1 (March 1966): 44-45. Flagstaff AZ: Arizona Academy of Science.
Available via JSTOR @ http://www.jstor.org/stable/40034171

Roberts, Kory (kaptainkory). 3 January 2007. "Prairie Racerunner (Aspidoscelis sexlineata viridis)." Herps of Arkansas > Lizards.
Available @ http://www.herpsofarkansas.com/Lizard/AspidoscelisSexlineata

Trauth, Stanley E. 1992. "A New Subspecies of Six-lined Racerunner, Cnemidophorus sexlineatus (Sauria: Teiidae), from Southern Texas: Cnemidophorus sexlineatus new subspecies." Texas Journal of Science, vol. 44, no. 4 (January 1992): 437-443. Lubbock TX: Texas Academy of Science.
Available via ResearchGate @ https://www.researchgate.net/publication/242553746/

Trauth, Stanley E. 1995. "An Emendation to the Subspecies Name Cnemidophorus sexlineatus stephensi (Sauria: Teiidae): Chemidophorus sexlineatus stephensae." Bulletin of the Chicago Herpetological Society, vol. 30, no. 4 (April 1995): 68. Chicago IL: Chicago Herpetological Society.
Available @ http://www.chicagoherp.org/bulletin/30(4).pdf

Uetz, Peter. "Aspidoscelis sexlineatus (Linnaeus, 1766)." Reptile Database.
Available @ http://reptile-database.reptarium.cz/species?genus=Aspidoscelis&species=sexlineatus&search_param=%28%28search%3D%27Cnemidophorus+sexlineatus%27%29%29

Wildcat Glades Conservation & Audubon Center @wildcatglades. 25 May 2014. "I saw a couple Six-lined Racerunner lizards today on the trail." Facebook.
Available @ https://www.facebook.com/wildcatglades/photos/a.97213991452.89001.72183971452/10152128990506453/