FLAT-HEADED SNAKE
Tantilla gracilis
Baird & Girard 1853


tăn-tĭl-ă — gră-sĭl-ŭs




An adult Flat-headed Snake from Crawford County, Kansas. © Suzanne L. Collins, CNAH.
Image © Suzanne L. Collins, CNAH.
An adult from Cherokee County. Image © Suzanne L. Collins, CNAH.
An adult from Waubaunsee County. Image © Suzanne L. Collins, CNAH.

Description:
HARMLESSLY VENOMOUS. Uses its venom to subdue prey, but is not dangerous to humans because a) they have an ineffective venom delivery mechanism, b) their mouths too small to gain purchase, and c) their venom is not adapted for causing physiological damage to mammals.
Scales smooth. Head slightly darker than the body. Body overall light gray tan to brown to reddish-brown with a salmon-pink belly. Six scales on each upper lip. Young same as adults. Diminutive (up to 20 cm TL) plain tan or yellow-brown snake with a pointed head. Belly bright salmon or orange in the middle, becoming white toward the sides. Flattened head; minute eyes; back scales smooth and in 15 rows; anal plate divided.
Adults normally grow 180-203 mm (7- 8 inches) in TL; largest specimen from Kansas: female (KU 83480) from Cowley County with TL of 244 mm (9 5/8 inches) collected by Charles E. Burt between 1938 and 1941; maximum length throughout range: 9 7/8 inches (Conant and Collins, 1998).


Distribution:
Generally found east of the Flint Hills and south of the Drift Hills.

(, Museum Voucher) (, Observation) (, Literature Record)
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  • Occurrence Summary:  
  • 1,133 Total Records 
  • 1,095 Museum Vouchers 
  • 38 Other Observations 
Some county occurrences indicated below may be too imprecise to map above.
County Breakdown: County Name (# occurrences):
Allen (5); Anderson (77); Atchison (3); Bourbon (20); Butler (4); Chase (65); Chautauqua (37); Cherokee (88); Clark (1); Cowley (521); Crawford (10); Douglas (60); Elk (10); Geary (5); Greenwood (24); Jefferson (10); Johnson (25); Labette (3); Leavenworth (15); Lyon (2); Montgomery (19); Neosho (9); Pottawatomie (30); Riley (59); Sumner (1); Wabaunsee (2); Wilson (27); Woodson (1);

Natural History:
Found in varying habitats, from wooded hillsides to prairie rock outcrops, and rural areas to city parks, but always under such as flat rocks, boards and sheet metal. Very secretive; rarely seen in the open. Never bites. Eats small invertebrates such as centipedes and spiders and probably insects and their larvae.
Mates in April and May and deposits 2-4 eggs in moist soil or under rocks during June. Young hatch in September at 7-0 cm TL.

Occurrence Activity:
White dates indicate there is at least a single recorded occurrence on that date. The darker blue a date is, the greater the relative number of observations for that date.
Remarks:
First reported in Kansas by Hallowell (1856). The earliest existing specimen is from 1909 (KU 1794).
Specimens are conspicuously absent from much of the Neosho River drainage basin. A distributional phenomenon exhibited by several additional taxa.
Two small, grooved rear fangs and small venom glands are apparently used in subduing prey, but the snake is no threat to human beings and does not bite when handled.

Bibliography:
1857 Hallowell, Edward. Notice of a collection of reptiles from Kansas and Nebraska presented to the Academy of Natural Sciences, by Doctor Hammond, U. S. A. Proceedings of the Academy of Natural Sciences, Philadelphia 8():238-253
1860 Cope, Edward D. Catalogue of Colubrdae in the Museum of  the Academy of Natural Sciences of Pailadelphia [sic]. I. Calamarinae. Proceedings of the Academy of Natural Sciences, Philadelphia 12():74-79
1883 Garman, Samuel. The reptiles and batrachians of North America.  Kentucky Geological Survey. Yeoman Press., Frankfort, Kentucky. 185pp.
1883 Garman, Samuel. The reptiles and batrachians of North America. Memiors of the Museum of Comparative Zoology, Harvard University 8(3):xxxi + 1-185
1884 Garman, Samuel. The North American reptiles and batrachians. Bulletin of the Essex Institute 16():1-46
1885 Cragin, Francis W. Recent additions to the list of Kansas reptiles and batrachians, with further notes on species previously reported. Bulletin of the Washburn College Laboratory of Natural History 1(3):100-103
1885 Cragin, Francis W. Second contribution to the herpetology of Kansas, with observations on the Kansas fauna. Transactions of the Kansas Academy of Science 9():136-140
1904 Branson, Edwin B. Snakes of Kansas. University of Kansas Science Bulletin 2(13):353-430
1928 Burt, Charles E. Some distributional and ecological records of Kansas reptiles. Transactions of the Academy of Science St. Louis 26():186-208
1929 Taylor, Edward H. A revised checklist of the snakes of Kansas. University of Kansas Science Bulletin 19(5):53-62
1934 Burt, Charles E. and W. L. Hoyle. Additional records of the reptiles of the central prairie region of the United States. Transactions of the Kansas Academy of Science 37():193-216
1935 Burt, Charles E. Further records of the ecology and distribution of amphibians and reptiles in the middle west. American Midland Naturalist 16(3):311-366
1935 Burt, Charles E. and William L. Hoyle. Additional records of the reptiles of the central prairie region of the United States Transactions of the Kansas Academy of Science 37():193-216
1936 Taylor, Edward H. Notes and comments on certain American and Mexican snakes of the genus Tantilla with descriptions of new species. Transactions of the Kansas Academy of Science 39():335-348
1953 Schmidt, Karl P. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.
1956 Loomis, Richard B. The chigger mites of Kansas (Acarina, Trombiculidae). University of Kansas Science Bulletin 37():1195-1443
1956 Smith, Philip W. Extension of known range of the flat-headed snake. Herpetologica 12():327
1976 Caldwell, Janalee P. and Gregory. Glass. Vertebrates of the Woodson County State Fishing Lake and Game Management Area. Pages 62-76 in Preliminary inventory of the biota of Woodson County State Fishing Lake and Game Management Area. Report No. 5. State Biological Survey of Kansas, Lawrence. pp.
1977 Van Devender, Robert Wayne, and Charles J. Cole. Notes on a colubrid snake, Tantilla vermiformis, from Central America . American Museum Novitates (2625):1-12
1982 Fitch, Henry S. Resources of a snake community in prairie-woodland habitat of northeastern Kansas. Pages 83-97 in Herpetological communities: A symposium of the Society for the Study of Amphibians and Reptiles and the Herpetologists League, August 1977.  Wildlife Research Reports 12. 239 pp. U. S. Fish and Wildlife Service, Washington, D. C. pp.
1982 Wilson, Larry David. Tantilla. Catalogue of American Amphibians and Reptiles (307):1-4
1991 Fitch, Henry S. Reptiles and amphibians of the Kansas ecological reserves. Pages 71-74 in Multidisciplinary Guidebook 4. Kansas Academy of Science, Lawrence. pp.
1996 Miller, Larry L. Many amphibian and reptile species identified during KHS 1996 fall field trip to Wabaunsee County. Kansas Herpetological Society Newsletter (106):2-3
2000 Taggart, Travis W. Results of the KHS 2000 fall field trip. Kansas Herpetological Society Newsletter (122):6-8
2005 Taggart, Travis W. Results of the KHS 2005 fall field trip [to Crawford County]. Journal of Kansas Herpetology (16):19-21
2006 Taggart, Travis W. Distribution and status of Kansas herpetofauna in need of information. State Wildlife Grant T7. Kansas Department of Wildlife and Parks, Pratt. vii + 106pp.
2008 Taggart, Travis W. KHS 2008 spring field trip. Journal of Kansas Herpetology (25):2-3
2012 Rohweder, Megan R. Spatial conservation prioritization of Kansas for terrestrial vertebrates. Thesis. Fort Hays State University, Hays, Kansas. 151pp.
2016 Pittman, Galen L., Henry S. Fitch, and W. Dean Kettle Vertebrate animals on the Fitch Natural History Reservation (1948-2002) Kansas Biological Survey Report Number 188, Lawrence. 48pp.
2018 Cox, Christian L., Joel F. Stringer, Matthew a. Moseley, Paul T. Chippindale, and Jeffery W. Streicher. Testing the geographical dimensions of genetic diversity following range expansion in a North American snake. Biological Journal of the Linnean Society 2018(125):586–599
Account Last Updated:
5/14/2019 12:09:52 PM


Travis W. Taggart © 2020 — Sternberg Museum of Natural History, Fort Hays State University