This site will look much better in a browser that supports web standards, but it is accessible to any browser or Internet device.


Sistrurus miliarius (Linnaeus, 1766) - Western Pygmy Rattlesnake


Maps

Locality Map

Locality map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

County Map

County map for Sistrurus miliarius (Western Pygmy Rattlesnake)
County map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Historical Locality Map

Historical locality map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Historical locality map for Sistrurus miliarius (Western Pygmy 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 6 March 2024.

Historical County Map

Historical county map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Historical county map for Sistrurus miliarius (Western Pygmy 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 6 March 2024.

Ecological Drainage Locality Map

Ecological Drainage Units map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Ecological Drainage Units locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Natural Divisions Locality Map

Natural Divisions locality map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Natural Divisions and Sections locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Major Watersheds Locality Map

Major watersheds map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Major Watersheds locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Level I Ecoregion Locality Map

Level I Ecoregions map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Level I Ecoregion locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Level II Ecoregion Locality Map

Level II Ecoregions map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Level II Ecoregion locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Level III Ecoregion Locality Map

Level III Ecoregions map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Level III Ecoregion locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Level IV Ecoregion Locality Map

Level IV Ecoregions map for Sistrurus miliarius (Western Pygmy Rattlesnake)
Level IV Ecoregion locality map for Sistrurus miliarius (Western Pygmy Rattlesnake).
Map created 6 March 2024.

Native Status

Sistrurus miliarius (Western Pygmy Rattlesnake) is native to Missouri.

Collection Summary

Sistrurus miliarius (Western Pygmy Rattlesnake) has a total of 128 valid, non-duplicated collections representing 16 counties and 79 localities. There are a total of 56 collectors and 74 collection dates for the species. This results in a total of 82 expeditions for the species, a measure of unique date / collector(s) combinations. The earliest collection year for the species in Missouri is 1900 and its most recent collection year is 2022. The earliest and latest collection dates (independent of earliest and most recent collection years) are April 1 and October 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 Sistrurus miliarius (Western Pygmy 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
Barry 3 5 5 5 5 1939 2014
Butler 2 2 1 2 2 1960 1962
Carter 2 9 4 3 4 1940 2008
Christian 6 10 10 6 6 1967 2022
Douglas 2 2 3 2 2 2008 2008
Howell 3 3 4 2 3 1938 1969
McDonald 1 1 1 1 1 2011 2011
Oregon 3 3 2 3 3 1900 1961
Ozark 11 19 10 11 11 1956 1998
Reynolds 2 3 3 3 3 1933 1938
Ripley 3 3 5 3 3 2008 2009
Shannon 9 11 11 10 10 1939 2017
Stone 4 10 3 6 6 1907 1931
Taney 12 17 12 13 14 1954 2021
Washington 2 2 2 2 2 1951 1951
Wayne 13 27 10 15 17 1933 2019

Potential County Records

Potential counties for Sistrurus miliarius (Western Pygmy 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 Iron Same Level IV ecoregion, within 5 miles St. Francois Knobs and Basins
2 Jefferson Same Level IV ecoregion, within 5 miles Meramec River Hills
2 Madison Same Level IV ecoregion, within 5 miles St. Francois Knobs and Basins
2 Saint Francois Same Level IV ecoregion, within 5 miles Meramec River Hills
4 Dent Same Level IV ecoregion, within 10 miles Current River Hills
4 Franklin Same Level IV ecoregion, within 10 miles Meramec River Hills
4 Greene Same Level IV ecoregion, within 10 miles Springfield Plateau
4 Texas Same Level IV ecoregion, within 10 miles Current River Hills
4 Texas Same Level IV ecoregion, within 10 miles White River Hills
4 Webster Same Level IV ecoregion, within 10 miles White River Hills
6 Bollinger Same Level IV ecoregion, within 20 miles Black River Hills Border
6 Bollinger Same Level IV ecoregion, within 20 miles St. Francois Knobs and Basins
6 Lawrence Same Level IV ecoregion, within 20 miles Springfield Plateau
6 Newton Same Level IV ecoregion, within 20 miles Dissected Springfield Plateau-Elk River Hills
6 Stoddard Same Level IV ecoregion, within 20 miles Black River Hills Border
6 Wright Same Level IV ecoregion, within 20 miles White River Hills
7 Sainte Genevieve Same Level III ecoregion, within 20 miles Ozark Highlands
8 Crawford Same Level IV ecoregion, within 30 miles Meramec River Hills
8 Dade Same Level IV ecoregion, within 30 miles Springfield Plateau
9 Phelps Same Level III ecoregion, within 30 miles Ozark Highlands
9 Saint Louis Same Level III ecoregion, within 30 miles Ozark Highlands

Linnaean Classification

Kingdom:
Animalia - Animals
Phylum:
Chordata - Chordates
Subphylum:
Vertebrata - Vertebrates
Class:
Reptilia Laurenti, 1768 - Reptiles
Order:
Squamata Oppel, 1811 - Lizards and Snakes
Suborder:
Serpentes Linnaeus, 1758 - Snakes
Family:
Viperidae Bonaparte, 1840 - Asps and Vipers
Genus:
Sistrurus Garman, 1883 - Massasaugas and Pygmy Rattlesnakes
Species:
Sistrurus miliarius (Linnaeus, 1766) - Western Pygmy Rattlesnake

Recent Taxonomic Synonyms

(none)