Field Guide to Maryland's Snakes (Order Squamata)

Sub-order Serpentes

Snakes
27 species an​d sub-species in Maryland

Snakes are limbless reptiles with elongate​​ bodies that are covered with scales. All snakes lack external ear openings and eyelids and have lo​ng, forke​d tongues. 

There are twenty-seven different va​rieties (species and sub-species) in two families of snakes that can be found in Maryland.​​

Two Maryland species, the copperhead (Agkistrodon contortrix) and timber rattlesnake (Crotalus horridus) are in the viper family (Viperidae). The remaining species are in the family Colubridae, which is the largest snake family in the world. 

Click here for a Table that shows whether the scales of each snake species are keeled, weakly-keeled, or smooth and whether the anal plate is single or divided. These characteristics along with the number of dorsal scale rows at the mid-body and the overall coloration and patterning are important characteristics used to differentiate species of snakes (White and White 2002). With a few exceptions, most young snakes resemble adults (Mitchell 1994). Eggs of snakes can be differentiated by species. However, characteristics used to identify species of snakes based on examination of eggs are not discussed in this document.

Sna​ke Anatomy​

​​​​S​nake Family​
Number of Species &
Subspecies in Maryland​
​Viper (Viperidae)
​2
​Colubridae​
​25

Pit Vipers (Subfamily Crotalinae)

There are two species of pit vipers found in Maryland, the timber rattlesnake (Crotalus horridus) and the copperhead, which includes the subspecies northern copperhead (Agkistrodon contortrix mokasen) and intergrade (Agkistrodon c. contortrix X mokasen). Both of these species are dangerously venomous and should be treated with caution. Do not approach or handle these snakes as a bite could be fatal. As the name implies the pit vipers have a heat seeking pit between each eye and nostril. The pit vipers also differ noticeably from the colubrids by having vertical pupils, and undivided subcaudal scales (Conant and Collins 1998).


Click on a picture or species name for profiles of each of the 2 species and subspecies of Maryland’s pit vipers.

PhotoCommon NameScientific NameState Status

Photo of Northern Copperhead courtesy of Linh Phu

Photo of Northern Copperhead courtesy of Linh Phu

Northern Copperhead
and
Intergrade

Agkistrodon contortrix mokasen
and
Agkistrodon c. contortrix X mokasen

Photo of Timber Rattlesnake courtesy of Scott A. Smith
 
Photo of Timber Rattlesnake courtesy of Scott A. Smith

Timber Rattlesnake

Crotalus horridus

​Watchlist

​​

Colubrids (Family Colubridae)

Maryland colubrids differ from vipers by having round pupils in the eyes, no heat seeking pit between each eye and nostril, a complete set of divided sub-caudal scales, and a series of large plates (scales) on the dorsum of the head.

There are 26 different types of snakes (including sub-species) from the family colubridae that can be found in Maryland. Due to the large number of genera (16) and the relatively few species within each genus (no more than two), identification of Maryland colubrids to genus is not discussed here. Species and sub-species descriptions follow. ​

​​

Click on a picture or species name for profiles
of each of the 25 species and subspecies of Maryland’s colubrids.

PhotoCommon NameScientific NameState Status

Photo of Adult Northern Watersnake courtesy of  Scott A. Smith

Photo of Adult Northern Watersnake courtesy of Scott A. Smith ​

Northern Water Snake

Nerodia sipedon sipedon

Photo of Red-bellied Watersnake courtesy of Dave Wilson
​ Photo of Red-bellied Watersnake courtesy of Dave Wilson

Red-bellied Watersnake​

Nerodia erythrogaster erythrogaster

​Watchlist​

Photo of Queen Snake courtesy of John White

Photo of Queen Snake courtesy of John White

Queen Snake

Regina septemvittata

Photo of Adult Eastern Smooth Earthsnake - courtesy of Jay Kilian
Photo of Adult Eastern Smooth Earthsnake
courtesy of Jay Kilian

Eastern Smooth Earthsnake

Virginia valeriae valeriae

Photo of Adult Mountain Earthsnake courtesy of Don Forester
Photo of Adult Mountain Earthsnake courtesy of Don Forester

Mountain Earthsnake

Virginia valeriae pulchra

​Endangered​​

 

Illustration of Juvenile Northern Brownsnake
Photo of Adult Northern Brownsnake courtesy of Scott A. Smith
Photo of Adult Northern Brownsnake courtesy of Scott A. Smith

 

Northern Brownsnake

Storeria dekayi dekayi

Photo of Adult Northern Red-bellied Snake courtesy of Mark Tegges
Photo of Adult Northern Red-bellied Snake courtesy of Mark Tegges​

Northern red-bellied Snake

Storeria occipitomaculata occipitomaculata

Photo of Eastern Gartersnake courtesy of John White
Photo of Eastern Gartersnake courtesy of John White

Eastern Gartersnake

Thamnophis sirtalis sirtalis

Photo of Common Ribbon Snake courtesy of John White
Photo of Common Ribbon Snake courtesy of John White

Common Ribbon Snake

Thamnophis sauritus sauritus

Photo of Northern Ring-necked Snake courtesy of Linh Phu
Photo of Northern Ring-necked Snake courtesy of Linh Phu

Photo of Southern Ring-necked Snake courtesy of Matt Close
Photo of Southern Ring-necked Snake courtesy of Matt Close

Northern Ring-Necked Snake and
Southern Ring-Necked Snake
and

Intergrade ​​

Diadophis punctatus edwardsii
Diadophis punctatus punctatus

Diadophis p. punctatus X edwardsi

Eastern Wormsnake - courtesy of Corey Wickliffe
Eastern Wormsnake - courtesy of Corey Wickliffe

Eastern Wormsnake​

Carphophis amoenus amoenus

Photo of Smooth Greensnake courtesy of Matt Sell
Photo of Smooth Greensnake courtesy of Matt Sell

Smooth Greensnake

Opheodrys vernalis

Photo of Northern Rough Greensnake courtesy of Linh Phu
Photo of Northern Rough Greensnake courtesy of Linh Phu

Northern Rough Greensnake

Opheodrys aestivus aestivus

Photo of Eastern Hog-nosed Snake courtesy of Corey Wickliffe
Photo of Eastern Hog-nosed Snake courtesy of Corey Wickliffe

Eastern Hog-nosed Snake

Heterodon platirhinos

Photo of Rainbowsnake courtesy of Lance Benedict
Photo of Rainbowsnake courtesy of Lance Benedict

Rainbow Snake

Farancia erytrogramma erytrogramma

​Endangered​

Photo of Adult Northern Black Racer courtesy of John White
Photo of Adult Northern Black Racer courtesy of John White

Northern Black Racer

Coluber constrictor constrictor

Photo of Northern Pinesnake courtesy of Scott A. Smith
Photo of Northern Pinesnake courtesy of Scott A. Smith

Northern Pinesnake

Pituophis melanoleucus melanoleucus

​Historical​

Photo of Adult Red Cornsnake courtesy of Linh Phu
Photo of Adult Red Cornsnake courtesy of Linh Phu

Red Cornsnake

Pantherophis guttatus

Photo of Adult Eastern Ratsnake courtesy of John White
Photo of Adult Eastern Ratsnake courtesy of John White

Eastern Ratsnake

Pantherophis alleghaniensis

Photo of Mole Kingsnake courtesy of John White
Photo of Mole Kingsnake courtesy of John White

Mole Kingsnake

Lampropeltis calligaster rhombomaculata

Photo of Eastern Kingsnake courtesy of John White
Photo of Eastern Kingsnake courtesy of John White

Eastern Kingsnake

Lampropeltis getula getula

Photo of Eastern Milksnake courtesy of John White
Photo of Eastern Milksnake courtesy of John White​

Eastern Milksnake

Lampropeltis triangulum triangulum

Coastal Plain Milksnake Photo courtesy of John White
Coastal Plain Milksnake Photo courtesy of John White​

Coastal Plain Milksnake

Lampropeltis triangulum elapsoides X triangulum

Photo of Adult Northern Scarletsnake courtesy of John White
Photo of Adult Northern Scarletsnake courtesy of John White

Northern Scarletsnake

Cemophora coccinea copei

​Watchlist​

​​

A number of documents were used to compile the snake descriptions that follow. The document that provided the most information was The Reptiles of Virginia by Joseph C. Mitchell (1994). Amphibians and Reptiles of Pennsylvania by Arthur C. Hulse, C. J. McCoy, and Ellen Censky (2001) and Amphibians and Reptiles of Delmarva by James F. and Amy Wendt White (2002) were also extremely useful. These books are recommended to anyone seeking more comprehensive information on North American snake ecology and identification.


In addition to physical descriptions of snakes, maps depicting the distribution of each snake species in Maryland are also included. The distribution maps include historical distributional information that was compiled by Harris (1975) and distributional surveys of select species by Thompson (1984). White and White (2002) provided a great deal of distributional information for snakes on Maryland’s eastern shore. Additional recent distribution information was provided by the Maryland Department of Natural Resources, Maryland Biological Stream Survey and Natural Heritage Program, and from additional literature where appropriate. ​​​​​​​​​​​​​​​​​​​​​​​