Kirtland's snake
Kirtland's snake (Clonophis kirtlandii) from southern Indiana
Conservation status
Near Threatened  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Colubridae
Genus:	Clonophis Cope, 1889
Species:	C. kirtlandii
Binomial name
Clonophis kirtlandii (Kennicott, 1856)
Synonyms
Regina kirtlandii Kennicott, 1856 Tropidonotus kirtlandii — Garman, 1884 Ischnognathus kirtlandii — Jan, 1860 Natrix kirtlandii — Cope, 1900 Clonophis kirtlandi — H. M. Smith & Brodie, 1982

Kirtland's snake (Clonophis kirtlandii) is a threatened or endangered (depending on location) North American species of nonvenomous snake of the subfamily Natricinae, of the family Colubridae.^[2] It is the only species in the genus Clonophis.^[3]

The specific name, kirtlandii, is in honor of Dr. Jared Potter Kirtland, an American naturalist of the nineteenth century.^[4][5] The snake was first identified by Robert Kennicott in 1855. Kennicott sent a specimen to Spencer Fullerton Baird, the assistant secretary of the Smithsonian Institution, who offered to publish a description of the animal in Kennicott's name. Baird suggested Regina kirtlandii as a scientific name, as Kirtland had been a mentor to Kennicott.^[6]

Common names for C. kirtlandii include: Cora Kennicott's snake, Kirtland's red snake, Kirtland's water snake, little red snake, Ohio Valley water snake, and spread head.^[7]

Kirtland's snake is small and slender. Adults reach a total length (including tail) of 12-18 inches (30–46 cm). It is grayish brown with a double series of large black spots down the back, and alternating smaller spots running down each side.^[8] The ventral scales are brick red with a prominent round black spot at each outer end.^[9] It has 19 rows of keeled dorsal scales at midbody, and the anal plate is divided.^[10]

Clonophis kirtlandii is currently known to occur in Illinois, Indiana, Kentucky, southern Michigan, northeastern Missouri, Ohio, and northwestern Tennessee.^[9][11] Clonophis kirtlandii was historically known from Western Pennsylvania, but it has not been documented in the state since 1966.^[11]

The preferred natural habitats of C. kirtlandii are forest, grassland, and wetlands^[1] such as swamps and marshes. It is almost always found very close to a water source, even though it is less aquatic than water snakes of the genus Nerodia which share its geographic range.^[7] Field studies have shown that populations are found within areas with abundant grass, herbaceous vegetation, and shrubs during the spring season. ^[12]

The species Clonophis kirtlandii is listed as endangered in Indiana,^[13] Michigan, and Pennsylvania.^[14] It is listed as threatened in Illinois and Ohio, though current research in Ohio is leaning towards the snake being listed as vulnerable.^{[citation needed]}

Kirtland's snake preys primarily on earthworms, slugs, minnows, salamanders, frogs, and toads.^[7] It has also been found to prey on juvenile crayfish, earthworms, slugs, small minnows, and leeches. ^[11]

When alarmed C. kirtlandii flattens its entire body to a remarkable thinness, and becomes rigid.^[15] Kirtland's snake will also coil up into a disc the size of about a quarter in an attempt to hide from potential threats. If this does not succeed, it will then flee instead of fight.^{[citation needed]}

No person on record has ever been bitten by a Kirtland's snake. This species prefers intimidation, hiding, and fleeing rather than any form of fighting.^[16]

Kirtland's snake is ovoviviparous. Females give birth in August and September. Brood size varies from 4 to 22. Each newborn is 13–17 cm (5–6¾ in.) in total length and averages 1.4 gm in weight.^[7]

• Behler, J.L., and F.W. King (1979). The Audubon Society Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knopf. 743 pp. ISBN 0-394-50824-6. ("Clonophis kirtlandi [sic]", p. 596 + Plate 551).
• Conant, R., and W. Bridges (1939). What Snake Is That? A Field Guide to the Snakes of the United States East of the Rocky Mountains. (With 108 drawings by Edmond Malnate). New York and London: D. Appleton-Century Company. Frontispiece map + viii + 163 pp. + Plates A-C, 1-32. (Natrix kirtlandii, p. 95 + Plate 16, figure 47).
• Kennicott, R. (1856). "Description of a new Snake from Illinois". Proc. Acad. Nat. Sci. Philadelphia 8: 95-96. (Regina kirtlandii, new species).
• McCoy, C.J. (1980). Identification Guide to Pennsylvania Snakes. (Design and illustrations by Michael Antonoplos). Pittsburgh Pennsylvania: Carnegie Museum of Natural History. 12 pp. (Clonophis kirtlandi, p. 8).
• Netting, M.G., and Richmond, N.D. (editors) (1970). Pennsylvania Reptiles and Amphibians. (Photographs by Hal H. Harrison). Third Edition, Fifth Printing. Harrisburg, Pennsylvania: Pennsylvania Fish Commission. 24 pp. (Natrix kirtlandii, p. 3).
• Powell, R., R. Conant, and J.T. Collins (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiv + 494 pp. ISBN 978-0-544-12997-9. (Clonophis kirtlandii, pp. 410–411+ Plate 40).
• Rossman, D.A. (1963). "Relationships and taxonomic status of the North American natricine snake genera Liodytes, Regina and Clonophis ". Occasional Papers of the Museum of Zoology, Louisiana State University (29): 1–29.
• Stejneger, L., and T. Barbour (1917). A Check List of North American Amphibians and Reptiles. Cambridge, Massachusetts: Harvard University Press. 125 pp. (Natrix kirtlandii, p. 95).

• Michigan state Department of Natural Resources entry
• The Center for Reptile and Amphibian Conservation and Management entry