The western ground snake (Sonora semiannulata) is a species of small, harmless colubrid snake. The species is endemic to North America. It is sometimes referred to as the common ground snake or variable ground snake, as its patterning and coloration can vary widely, even within the same geographic region.Stebbins, R.C. (2003). A Field Guide to Western Reptiles and Amphibians, Third Edition. The Peterson Field Guides Series ®. Boston and New York: Houghton Mifflin. xiii + 533 pp. . (Sonora semiannulata, pp. 391–393 + Plate 45 + Map 170). Another common name is miter snake referring to the head marking which suggests a bishop's miter; the synonym "episcopus " (Latin for "bishop") is a similar allusion.
No narrative description available for this taxon yet.
A DNA barcode is a short, standardised stretch of genes that works like a fingerprint — enough to tell one species from another. Below is the molecular trace Sonora semiannulata has left across the world's sequence archives.
At a glance
DNA specimens9
BINs2
Marker genes1
eDNA detections9
Countries1
The DNA barcodethe species' typical barcode, built from every sequenced specimen
COI-5P655 bp consensus8 specimens
ACGT
▸ drag or hover over the strip to read any position — letter and how much it varies
Violet ticks below the strip = positions where individuals differ; flat = the species' unchanging signature. 93% of positions are identical in every specimen.
Where individuals differ — all 45 variable positions, in barcode order
Each circle is a barcode variant; bigger = more specimens, colour = region. Lines join the most similar variants and the tick marks count the mutations between them — a tight cluster is one “dialect”, a long line a more divergent lineage. Click a circle to list its actual specimens.
Diversity (π)1.8%
Haplotypes4
BINs2
Most divergent pair6.0%
N.America
Closest relatives by DNA barcode
The species whose COI barcode is most similar to this one — a quick “who is this most like”. The percentage is how much the barcode differs; it approximates, but is not, the full evolutionary tree.
★ the standard DNA barcode for this group — the short region actually read to tell this species apart. The rest are extra genes sequenced along the way.
★COI-5P
animal barcode
07Deep time~7.98 Ma lineage
How far back this lineage goes — and how we know. Everything here is measured in Ma, short for “mega-annum”: millions of years ago. The chart reads left to right like a calendar of the Earth, from the deep past on the left to today at the right edgetop to bottom like a core drilled through the Earth, from the deep past at the top down to today at the bottom.
At a glance
DNA clock origin7.98 Ma TimeTree
When this lineage existed
How to read this: the coloured strip along the bottomdown the left is the geological calendar — the standard epochs (Pliocene, Pleistocene…) every museum uses, shown so you can see which chapter of Earth's history this lineage lived in. This lineage is a young one, so the strip is zoomed in to epochs — the finer subdivisions inside a period. The orange marker is the DNA clock: DNA accumulates mutations at a roughly steady rate, so comparing this species' DNA with its relatives estimates when the lineage split off — independently of any fossil.
DNA clock origin
08Occurrence & distribution
Record type5 871 records
Wild obs. + sensor785
Museum / vouchered5 086
Origin
Native856
Range
Area of Occupancy AOO8 428 km²
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
Coordinate accuracy58% within 1 km
≤100 m 317≤1 km 80≤10 km 48>10 km 244
689 georeferenced · 96 without coordinates
Open the mapobservation + sensor785
Museum / Voucheredphysical evidence
Backed by a physical specimen — a herbarium sheet, sample or voucher held in a collection. “Vouchered” means supported by material evidence, not just an observation.
Coordinate accuracy45% within 1 km
≤100 m 533≤1 km 905≤10 km 1 370>10 km 354
3 162 georeferenced · 1 924 without coordinates
Open the institutions mapphysical evidence5 086
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
10Collections & institutions
Holding institutions23 of 40 geolocated
Institutions and collections holding physical, vouchered specimens of this species — click a row to fly to it on the map.
Institution
Specimens
Washington, US
1 000
Texas Memorial Museum, Texas Natural History Collectionlocation not on record
538
Texas Cooperative Wildlife Collectionlocation not on record
462
Sam Noble Oklahoma Museum of Natural Historylocation not on record
441
München, DE
283
Wuzhou, CN
260
CASlocation not on record
243
University of Texas at Arlingtonlocation not on record
230
ASUlocation not on record
223
Zacatecas, MX
178
ASNHClocation not on record
177
San Diego, US
159
Berkeley, US
131
EL PASO, US
128
Ann Arbor, US
127
Provo, US
115
Fort Hays State University, Sternberg Museumlocation not on record
94
Los Angeles, US
74
Chongqing Museumlocation not on record
67
Universidad Católica de Manizaleslocation not on record
33
Cambridge, US
29
New Haven, US
19
University of Nevada, Museum of Biologylocation not on record
14
mcnhlocation not on record
8
Ciudad de México, MX
7
Tlalnepantla, MX
6
Chicago, US
5
Southeastern Louisiana University, Vertebrate Museumlocation not on record
5
Ensenada, MX
3
University of Nebraska State Museumlocation not on record
2
University of California Los Angeleslocation not on record
2
Toronto, CA
2
Tacoma, US
2
2
San Nicolás de los Garza, MX
2
Mexico City, MX
2
Florida Museum of Natural History- Zoology, Paleontology & Paleobotanylocation not on record
1
Philadelphia, US
1
Champaign, US
1
APSUlocation not on record
1
40 institutions · 5 077 of 5 086 vouchered records shown · 9 without an institution code
09Environmental DNA9 detections
Where the DNA of Sonora semiannulata was picked up in samples of water, soil or air — nobody saw the organism, only its DNA left behind. A trace is a clue that the species was near, not a confirmed sighting.
Signal
Detections DNA found9
Studies independent surveys1
Countries1
Signal confidence: weakweighed across independent studies, places & mapped detections
Where its DNA was found
0 of 9 detections have coordinates
Open the map1 country0
How strong is each trace?
DNA read depthRead counts were not reported for this species — the map shows presence only, not how strong each trace was.
Modelled climatemodelled
−15°Ctemperature across detection sites+40°C
Temperature median20.5 °C 18.4–21.4
Seasonal swing summer↔winter24.8 °C
Max temp (day)27.6 °C 25.2–28.3
Min temp (night)15.6 °C 13.0–16.4
Precipitation105 mm/mo 56.4–105
Air humidity55.2 % 52.3–55.5
Moisture balance-63.3 mm/mo -121–-63.3
Vapour deficit1,084 Pa 1,051–1,156
Wind speed4.50 m/s 4.30–5.20
Cloud cover36.8 % 33.0–37.2
CHELSA 1981–2010, ~9 km grid, at location & month of 8 detection points · median with p10–p90 · reflects where sampling happened, not only the true niche
How to read this: each dot is one detection of this species' DNA in an environmental sample. The confidence meter weighs how many independent studies and places back up the signal — one detection in one study is a hint; many across several studies is solid. Records dated before 2008 (when eDNA methods began) are treated as likely mislabeled and left off the map.
WikipediaWikimedia Foundation4 languages↗
BioWikiNetmultilingual Wikipediamultilingual↗
GBIFGlobal Biodiversity Information Facility5 871 records↗
ENAEuropean Nucleotide Archive · EMBL-EBI9 eDNA detections↗
BOLD SystemsCentre for Biodiversity Genomics9 specimens↗
Open Tree of LifeOpenTreephylogeny backbone↗
WikidataWikimedia Foundationstructured facts↗
GLoBIGlobal Biotic Interactionsbiotic interactions↗