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Crotalus horridus Linnaeus, 1758 - Timber Rattlesnake

Maps

Locality Map

Locality map for Crotalus horridus (Timber Rattlesnake)
Locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

County Map

County map for Crotalus horridus (Timber Rattlesnake)
County map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Historical Locality Map

Historical locality map for Crotalus horridus (Timber Rattlesnake)
Historical locality map for Crotalus horridus (Timber Rattlesnake). Black circles ( ) represent records after 1986, blue squares ( ) represent records between 1966 and 1986, orange triangles ( ) represent records prior to 1966. Note that more recent records might conceal underlying older records.
Map created 15 April 2026.

Historical County Map

Historical county map for Crotalus horridus (Timber Rattlesnake)
Historical county map for Crotalus horridus (Timber Rattlesnake). Black circles ( ) represent records after 1986, blue squares ( ) represent records between 1966 and 1986, orange triangles ( ) represent records prior to 1966. Note that only the most recent county record for each county is shown.
Map created 15 April 2026.

Ecological Drainage Locality Map

Ecological Drainage Units map for Crotalus horridus (Timber Rattlesnake)
Ecological Drainage Units locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Natural Divisions Locality Map

Natural Divisions locality map for Crotalus horridus (Timber Rattlesnake)
Natural Divisions and Sections locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Major Watersheds Locality Map

Major watersheds map for Crotalus horridus (Timber Rattlesnake)
Major Watersheds locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Level I Ecoregion Locality Map

Level I Ecoregions map for Crotalus horridus (Timber Rattlesnake)
Level I Ecoregion locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Level II Ecoregion Locality Map

Level II Ecoregions map for Crotalus horridus (Timber Rattlesnake)
Level II Ecoregion locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Level III Ecoregion Locality Map

Level III Ecoregions map for Crotalus horridus (Timber Rattlesnake)
Level III Ecoregion locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Level IV Ecoregion Locality Map

Level IV Ecoregions map for Crotalus horridus (Timber Rattlesnake)
Level IV Ecoregion locality map for Crotalus horridus (Timber Rattlesnake).
Map created 15 April 2026.

Native Status

Crotalus horridus (Timber Rattlesnake) is native to Missouri.

Collection Summary

Crotalus horridus (Timber Rattlesnake) has a total of 381 valid, non-duplicated collections representing 75 counties and 209 localities. There are a total of 102 collectors and 170 collection dates for the species. This results in a total of 181 expeditions for the species, a measure of unique date / collector(s) combinations. The earliest collection year for the species in Missouri is 1898 and its most recent collection year is 2024. The earliest and latest collection dates (independent of earliest and most recent collection years) are February 14 and November 20, respectively. If you have a new record to report, read the New Records section of the FAQ.

Collection Summary by County

Collection summary for Crotalus horridus (Timber Rattlesnake) by county. Some values are unavailable since some records are represented solely by historical literature reports, which sometimes lack complete collecting data. Click on a county name to view more information about that county. Click on column headings to sort by that column.
County Localities Collections Collectors Dates Expeditions Earliest Year Latest Year
Adair 1 2 2 2 2 1959 1965
Andrew 1 1 2 1 1 1992 1992
Barry 1 1 1 1 1 2003 2003
Barton 1 2 1 2 2 1900 1900
Bates 2 4 1 2 2 1958 1958
Benton 1 1 1 1 1 2015 2015
Bollinger 1 1 1 1 1
Boone 13 15 12 13 14 1934 2014
Buchanan 1 1 1 1 1
Butler 1 1 3 1 1 2007 2007
Caldwell 3 10 1 3 3 1954 1954
Callaway 2 2 2 2 2 1999 1999
Cape Girardeau 3 3 3 2 3 1972 1995
Carroll 1 2 1 2 2 1961 1961
Carter 1 2 3 2 2 1931 1931
Cass 1 3 1 2 2 1942 1942
Chariton 1 1 1 1 1 1940 1940
Christian 4 4 1 3 3 2011 2013
Clark 1 1 1 1 1
Clay 5 10 2 4 4 1939 1958
Clinton 1 1 1 1 1
Cooper 1 1 1 1 1 2017 2017
Dade 1 1 1 1 1 2018 2018
Dallas 1 1 1 1 1 2007 2007
Daviess 2 2 4 2 2 2014 2014
Dent 1 1 2 1 1 1997 1997
Dunklin 1 1 1 1 1 1900 1900
Gentry 4 4 2 4 4 2000 2003
Grundy 5 6 3 3 3 1964 2006
Harrison 1 1 1 1 1 2006 2006
Henry 2 2 1 1 1
Hickory 1 1 1 1 1 2005 2005
Holt 9 13 3 9 10 1959 1974
Howard 1 1 1 1 1
Howell 1 1 1 1 1 1909 1909
Iron 3 3 3 3 3 2009 2023
Jackson 30 82 6 32 32 1929 2003
Jefferson 4 6 3 3 3 1898 2009
Johnson 6 9 3 6 6 1909 1991
Laclede 1 1 1 1 1 2002 2002
Lafayette 1 2 1 2 2 1939 1939
Lincoln 1 1 1 1 1 2016 2016
Livingston 2 2 2 2 2 1940 2020
Madison 1 2 5 1 2 2007 2007
McDonald 2 2 2 2 2 2021 2021
Mercer 1 1 2 1 1 2018 2018
Moniteau 1 1 1 1 1 2012 2012
Monroe 2 2 4 2 2 2001 2017
Montgomery 3 3 4 3 3 1995 2015
Morgan 1 1 1 1 1 1948 1948
Osage 2 2 2 2 2 1996 2006
Perry 1 1 4 1 1 2008 2008
Pettis 7 11 5 7 8 1939 1976
Pike 6 18 2 4 5 1938 1939
Platte 6 8 2 3 3 1948 2024
Ralls 2 2 2 2 2 1979 2012
Ray 5 59 5 9 9 1951 2020
Reynolds 1 1 2 1 1 2008 2008
Ripley 1 1 2 1 1 2013 2013
Saint Charles 1 1 1 1 1 2003 2003
Saint Clair 1 1 1 1 1 2005 2005
Sainte Genevieve 1 1 1 1 1 1902 1902
Saint Francois 1 1 1 1 1 2019 2019
Saint Louis 7 8 4 3 5 1907 2009
Saline 2 3 1 2 2 1940 1940
Schuyler 1 1 1 1 1 2009 2009
Scott 2 4 1 2 2 1985 1985
Shannon 3 3 3 3 3 1992 2011
Stoddard 3 11 4 8 8 1935 1969
Stone 2 3 2 2 2 1908 1908
Sullivan 3 3 3 3 3 2008 2012
Taney 1 1 1 1 1 2000 2000
Warren 2 2 2 2 2 1993 2020
Washington 2 2 2 2 2 2003 2003
Wayne 8 9 11 7 7 1956 2015

Potential County Records

Potential counties for Crotalus horridus (Timber Rattlesnake). Counties are listed in descending order of their likelihood of having this species. Click on a county to view more information about that county. Click on column headings to sort by that column.
Likelihood County Rationale Ecoregion / Watershed
2 Audrain Same Level IV ecoregion, within 5 miles Claypan Prairie
2 Camden Same Level IV ecoregion, within 5 miles Osage/Gasconade Hills
2 Cole Same Level IV ecoregion, within 5 miles River Hills
2 Crawford Same Level IV ecoregion, within 5 miles Meramec River Hills
2 De Kalb Same Level IV ecoregion, within 5 miles Loess Flats and Till Plains
2 Franklin Same Level IV ecoregion, within 5 miles River Hills
2 Franklin Same Level IV ecoregion, within 5 miles Eastern Ozark Border
2 Gasconade Same Level IV ecoregion, within 5 miles River Hills
2 Linn Same Level IV ecoregion, within 5 miles Loess Flats and Till Plains
2 Maries Same Level IV ecoregion, within 5 miles Central Plateau
2 Miller Same Level IV ecoregion, within 5 miles Osage/Gasconade Hills
2 Putnam Same Level IV ecoregion, within 5 miles Loess Flats and Till Plains
4 Atchison Same Level IV ecoregion, within 10 miles Missouri Alluvial Plain
4 Cedar Same Level IV ecoregion, within 10 miles Springfield Plateau
4 Greene Same Level IV ecoregion, within 10 miles Springfield Plateau
4 Lewis Same Level IV ecoregion, within 10 miles Loess Flats and Till Plains
4 Macon Same Level IV ecoregion, within 10 miles Loess Flats and Till Plains
4 Marion Same Level IV ecoregion, within 10 miles River Hills
4 Newton Same Level IV ecoregion, within 10 miles Dissected Springfield Plateau-Elk River Hills
4 Oregon Same Level IV ecoregion, within 10 miles Current River Hills
4 Phelps Same Level IV ecoregion, within 10 miles Meramec River Hills
4 Texas Same Level IV ecoregion, within 10 miles Current River Hills
6 Douglas Same Level IV ecoregion, within 20 miles White River Hills
6 Jasper Same Level IV ecoregion, within 20 miles Springfield Plateau
6 Knox Same Level IV ecoregion, within 20 miles Loess Flats and Till Plains
6 Knox Same Level IV ecoregion, within 20 miles Claypan Prairie
6 Lawrence Same Level IV ecoregion, within 20 miles Springfield Plateau
6 Nodaway Same Level IV ecoregion, within 20 miles Loess Flats and Till Plains
6 Nodaway Same Level IV ecoregion, within 20 miles Rolling Loess Prairies
6 Ozark Same Level IV ecoregion, within 20 miles White River Hills
6 Polk Same Level IV ecoregion, within 20 miles Springfield Plateau
6 Polk Same Level IV ecoregion, within 20 miles Osage/Gasconade Hills
6 Pulaski Same Level IV ecoregion, within 20 miles Central Plateau
6 Randolph Same Level IV ecoregion, within 20 miles River Hills
6 Randolph Same Level IV ecoregion, within 20 miles Claypan Prairie
6 Scotland Same Level IV ecoregion, within 20 miles Loess Flats and Till Plains
6 Shelby Same Level IV ecoregion, within 20 miles River Hills
6 Webster Same Level IV ecoregion, within 20 miles Central Plateau
6 Webster Same Level IV ecoregion, within 20 miles White River Hills
6 Worth Same Level IV ecoregion, within 20 miles Loess Flats and Till Plains
6 Wright Same Level IV ecoregion, within 20 miles Central Plateau
7 Mississippi Same Level III ecoregion, within 20 miles Interior River Valleys and Hills
8 New Madrid Same Level IV ecoregion, within 30 miles St. Francis Lowlands
8 Vernon Same Level IV ecoregion, within 30 miles Wooded Osage Plains
8 Vernon Same Level IV ecoregion, within 30 miles Cherokee Plains
10 Pemiscot Same Level IV ecoregion, adjacent county St. Francis Lowlands

Linnaean Classification

Kingdom:
Animalia - Animals
Phylum:
Chordata - Chordates
Subphylum:
Vertebrata - Vertebrates
Class:
Reptilia Laurenti, 1768 - Reptiles
Order:
Squamata Oppel, 1811 - Lizards and Snakes
Family:
Crotalidae Oppel, 1811 - Pit Vipers
Genus:
Crotalus Linnaeus, 1758 - Rattlesnakes
Species:
Crotalus horridus Linnaeus, 1758 - Timber Rattlesnake

Recent Taxonomic Synonyms

(none)