The Florida cottonmouth (''Agkistrodon conanti'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

venomous snake ''Venomous snakes'' are species of the suborder Serpentes that are capable of producing venom, which they use for killing prey, for defense, and to assist with digestion of their prey. The venom is typically delivered by injection using hollow ...

, a

pit viper The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . or pit adders, are a subfamily (biology), subfamily of Viperidae, vipers found in Asia and the ...

in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Crotalinae The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . or pit adders, are a subfamily of vipers found in Asia and the Americas. Like all other vipers ...

of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Viperidae Vipers are snakes in the family Viperidae, found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, New Zealand, Ireland, and various other isolated islands. They are venomous snake, venomous and have long (relat ...

. The species is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the United States, where it occurs in southern

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

and the

Florida peninsula A peninsula ( from ''paene'' "almost" and ''insula'' "island") is a piece of land that is bordered mostly by water but connected to mainland. The surrounding water is usually understood to be continuous, though not necessarily named as such. A p ...

in nearly every type of wetlands in the region, including brackish water and offshore islands. However, it is not entirely dependent on water and is occasionally encountered as far as a mile (1.6 km.) from surface water. ''Agkistrodon conanti'' venom is very

hemolytic Hemolysis or haemolysis (), also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid (e.g. blood plasma). Hemolysis may occur in vivo ...

and known to cause relatively extensive

necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who i ...

compared to many snake venoms, and can sometimes be lethal with a 17% mortality rate. Ernst CH, Ernst EM (2011). ''Venomous Reptiles of the United States, Canada, and Northern Mexico, Volume 1: ''Heloderma, Micruroides, Micrurus, Pelamis, Agkistrodon, Sistrurus. Baltimore: The Johns Hopkins University Press. xviii + 352 pp. It is often confused with harmless watersnakes (''

Nerodia ''Nerodia'' is a genus of nonvenomous colubrid snakes commonly referred to as water snakes due to their aquatic behavior. The genus includes nine species, all native to North America. Five of the species have recognized subspecies. Descript ...

'') and other semi-aquatic species with which it shares its habitat. It is a moderately large, thick bodied snake, adults averaging 30 to 48 inches (76-122 cm) in length, but rare individuals can exceed 6 feet (183 cm). The head is marked with conspicuous black cheek stripes on each side, set off by light cream or white stripes above and below. The body is olive brown, dark brown, to black and with 10 to 17 dark bands. The dark bands are often darker at the edges but lighter with irregular markings or spotting in the center. The snakes often grow darker with age, and the banding and patterns can be obscure or absent on adults. It is a

viviparous In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juve ...

species, normally giving birth to 6 to 8 young, which bear the same pattern as adults but are clay-red or " red dirt" in color. It was first described in the late 1960s as a subspecies, A''gkistrodon piscivorus conanti'', however molecular research published in 2015 justified elevating it to a full species. Gloyd HK, Conant R (1990). ''Snakes of the ''Agkistrodon'' Complex: A Monographic Review.'' Society for the Study of Amphibians and Reptiles. 614 pp. 52 plates. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere.'' Ithaca and London: Comstock Publishing Associates. 870 pp. 1,500 plates. Powell R, Conant R, Collins JT (2016). ''Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition''. Boston and New York: Houghton Mifflin Harcourt Publishing Co. xiv + 494 pp., 47 Plates, 207 Figures. Crother BI (editor) (2017). ''Scientific and Standard English Names of Amphibians and Reptiles of North America North of Mexico, with Comments Regarding Confidence in Our Understanding, 8th. edition.'' SSAR Herpetological Circular 43, 102 pp. (page 59)

Etymology

In the original description,

Howard K. Gloyd Howard Kay Gloyd (February 12, 1902 – August 7, 1978) was an American herpetologist who is credited with describing several new species and subspecies of reptiles, such as the Florida cottonmouth, '' Agkistrodon piscivorus conanti''. He is honor ...

wrote it was "named in honor of a friend and colleague, Roger Conant, Director of the

Philadelphia Zoological Garden The Philadelphia Zoo is a zoo located in the Centennial District (Philadelphia), Centennial District of Philadelphia on the west bank of the Schuylkill River. It was the first true zoo in the United States; it was chartered by the Commonwealth ...

, whose professional achievements and dynamic promotion of the study of herpetology for amateurs merit highest commendation."Gloyd HK (1969). "Two additional subspecies of North American crotalid snakes, genus ''Agkistrodon'' ". ''Proceedings of the Biological Society of Washington'' 82: 219-232 . Roger Conant wrote ''Reptile Study'' for the

Boy Scouts of America Scouting America is the largest scouting organization and one of the largest List of youth organizations, youth organizations in the United States, with over 1 million youth, including nearly 200,000 female participants. Founded as the Boy Sco ...

merit badge Merit badges are awards earned by members of Scouting America, based on activities within the area of study by completing a list of periodically updated requirements. The purpose of the merit badge program is to allow Scouts to examine subjects ...

series and the original ''Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America'', one of the most popular and authoritative field guides on North American herpetofauna. He was a leading authority on North American watersnakes (''

''),Conant R (1969). "A Review of the Water Snakes of the Genus ''Natrix'' in Mexico". ''Bulletin of the American Museum of Natural History'' 142: 1-140. and with Gloyd, he coauthored a seminal monograph on the genus ''Agkistrodon''. Conant also named the southern cantil (''

Agkistrodon howardgloydi ''Agkistrodon howardgloydi'' is a species of venomous snake, a pit viper in the subfamily Crotalinae of the family Viperidae. The species is endemic to Central America. It is most commonly called ''castellana'', Conant, R. (1984). "A new subspeci ...

)'' in honor of Gloyd.Conant R (1984). "A new subspecies of the pit viper ''Agkistrodon bilineatus'' (Reptilia: Viperidae) from Central America". ''Proceedings of the Biological Society of Washington'' 97: 135-141.

Taxonomy and phylogenetics

The Florida cottonmouth is one of eight species in the genus ''

Agkistrodon ''Agkistrodon'' is a genus of pit vipers commonly known as American moccasins.Crother, B. I. (ed.). 2017. ''Scientific and Standard English Names of Amphibians and Reptiles of North America North of Mexico, with Comments Regarding Confidence in ...

'' that includes the copperheads, cottonmouths, and cantils. Molecular evidence indicates the genus ''Agkistrodon'' is a

monophyletic group In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

, meaning they all share a common ancestor. The copperheads (''

Agkistrodon contortrix The eastern copperhead (''Agkistrodon contortrix''), also known simply as the copperhead, is a widespread species of venomous snake, a pit viper, endemic to eastern North America; it is a member of the subfamily Crotalinae in the Family (biology ...

'' and '' A. laticinctus'') are the most basal (ancestral) living lineage of the genus, with the cottonmouths (''

Agkistrodon piscivorus ''Agkistrodon piscivorus'' is a species of venomous snake, a pit viper in the subfamily Crotalinae of the family Viperidae. It is one of the world's few semiaquatic vipers (along with the Florida cottonmouth), and is native to the Southeaster ...

'' and ''A. conanti)'' basal to Taylor's cantil ('' A. taylori)'', and ''A. taylori'' basal to the remaining cantils of Latin America. Parkinson CL, Zamudio KR, Greene HW (2000). "Phylogeography of the pitviper clade ''Agkistrodon'': historical ecology, species status and conservation of cantils". ''Molecular Ecology'' 9: 411-420. The northern cottonmouth (''

'') is the

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

(closest relative) of the Florida cottonmouth (''Agkistrodon conanti)''. Burbrink FT, Guiher TJ (2015). "Considering gene flow when using coalescent methods to delimit lineages of North American pitvipers of the genus ''Agkistrodon'' ". ''Zoological Journal of the Linnean Society'' 173: 505–526 The Florida cottonmouth was first described as a subspecies, ''Agkistrodon piscivorus conanti'', as recently as 1969. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

is a young adult male in the

United States National Museum The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums, Education center, education and Research institute, research centers, created by the Federal government of the United States, U.S. government "for the increase a ...

(USNM 165962), and the type locality is "at the edge of Rochelle-Cross Creek Road, about 7 miles southeast of Gainesville,

Alachua County, Florida Alachua County ( ) is a county in the north central portion of the U.S. state of Florida. As of the 2020 census, the population was 278,468. The county seat is Gainesville, the home of the University of Florida. History Prehistory and ear ...

" . Seven additional paratypes were designated in the original description. ''Agkistrodon conanti'' was elevated to a full species in 2015 based on molecular data,

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

evidence, and distinct

ecological niches In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for e ...

.Guiher TJ, Burbrink FT (2008). "Demographic and phylogeographic histories of two venomous North American snakes of the genus ''Agkistrodon'' ". ''Molecular Phylogenetics and Evolution'' 48: 543–553. Several subsequent reviews and species accounts supported the recognition of ''Agkistrodon conanti'' as a species. Uetz P, Freed P, Aguilar R, Hošek J (editors) (2021). The Reptile Database
''Agkistrodon conanti'' Gloyd, 1969
(accessed 6 August 2021)

Description

Adults of ''A. conanti'' grow up to 1,892 mm (74.5 inches) in total length (including tail).

Allen Allen, Allen's or Allens may refer to: Buildings * Allen Arena, an indoor arena at Lipscomb University in Nashville, Tennessee * Allen Center, a skyscraper complex in downtown Houston, Texas * Allen Fieldhouse, an indoor sports arena on the Univ ...

and Swindell (1948) reported one male specimen from

Marion County, Florida Marion County is a county located in the North Central region of the U.S. state of Florida. As of the 2020 United States census, the population was 375,908. Its county seat is Ocala. Marion County comprises the Ocala, Florida Metropolitan S ...

that measured 1,829 mm (72 inches) in total length and weighed 4.6 kg (10 pounds). The color pattern is very similar to that of '' A. piscivorus'', apart from head markings that are plainly visible even in older darker specimens of ''A. conanti'': with dark postocular stripes that are bordered above and below by narrow light lines. A pair of dark stripes are also visible at the front of the lower jaw. Mature specimens often lack any dorsal pattern, while the dorsal patterns of juveniles are more pronounced. Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . The Florida cottonmouth (''Agkistrodon conanti)'' differs from the northern cottonmouth (''Agkistrodon piscivorus'') in having a pair of dark vertical lines at the tip of the snout (running down the seams of the

rostral Rostral may refer to: Anatomy * Rostral (anatomical term), situated toward the oral or nasal region * Rostral bone, in ceratopsian dinosaurs * Rostral organ, of certain fish * Rostral scale The rostral scale, or rostral, in snakes and other sca ...

prenasals In reptiles, the nasal scale refers to the scale that encloses the nostril. Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. . Somet ...

, and first

supralabial scales In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates ( ...

). Additionally the patterns and markings on the head of the Florida cottonmouth are typically lighter, cleaner, and more sharply defined in all except a few old individuals. ''Agkistrodon conanti'' also has a longer tail, mean relative tail length 17.4% in adult and subadult males (mean relative tail length 15.9% in adult and subadult males in ''Agkistrodon piscivorus''). The cottonmouths differs from all other members of the genus ''

'' in the absence of a

loreal scale The lore (adj. loreal) is the region between the eyes and nostrils of birds, reptiles, and amphibians. Ornithology In ornithology, the lore is the region between the eye and bill on the side of a bird's head. This region is sometimes featherless ...

and 25 mid-body

dorsal scale In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...

rows, rarely 23 or 27 (mid-body dorsal scale rows typically 23 arely 21 or 25and loreal scale present in all other species). Additionally, the third

supralabial In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates ( ...

usually reaches the eye orbit (small scales are usually between supralabials and the eye orbit in all other species).

Distribution

''Agkistrodon conanti'' is found in the southeast of the United States, throughout the

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

peninsula, including many

barrier islands Barrier islands are a coastal landform, a type of dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few is ...

and keys, and into southern

. The Florida cottonmouth ranges into the

Florida Keys The Florida Keys are a coral island, coral cay archipelago off the southern coast of Florida, forming the southernmost part of the continental United States. They begin at the southeastern coast of the Florida peninsula, about south of Miami a ...

at least as far as

Key Vaca Key Vaca is an island in the middle Florida Keys, located entirely within the borders of the city of Marathon, Florida. Geography Key Vaca is located in between Fat Deer Key and Knight's Key. Vaca Key was also connected via bridge to Boot Key ...

. The exact origin of a 19th century record from

Key West Key West is an island in the Straits of Florida, at the southern end of the U.S. state of Florida. Together with all or parts of the separate islands of Dredgers Key, Fleming Key, Sunset Key, and the northern part of Stock Island, it con ...

is questionable, although by the end of the 20th century, no additional records had appeared and no suitable habitat remains there. Sources vary on the exact areas and extent of the zone of integration between ''A. conanti'' and ''A. piscivorus''. Earlier subspecies accounts all mapped different and various regions of integration.Conant R, Collins JT (1998). ''A Field Guide to Reptiles and Amphibians, Eastern and Central North America, Third Edition, Expanded.'' Peterson Field Guide Series. Boston: Houghton Mifflin Co. xviii + 616 pp. ISBN 0-395-90452-8 In one study

ecological niche In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of Resource (biology), resources an ...

models predicted

hybridization Hybridization (or hybridisation) may refer to: *Hybridization (biology), the process of combining different varieties of organisms to create a hybrid *Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals *Nu ...

might occur from

North Carolina North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ...

to the southern coastal plains in southeastern

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

, however molecular data (DNA) from the same study indicated samples from individuals from the

Savannah, Georgia Savannah ( ) is the oldest city in the U.S. state of Georgia (U.S. state), Georgia and the county seat of Chatham County, Georgia, Chatham County. Established in 1733 on the Savannah River, the city of Savannah became the Kingdom of Great Brita ...

area northward, as well as from areas north and west of

Mobile Bay, Alabama Mobile Bay ( ) is a shallow inlet of the Gulf of Mexico, lying within the state of Alabama in the United States. Its mouth is formed by the Fort Morgan Peninsula on the eastern side and Dauphin Island, a barrier island on the western side. The ...

were ''A. piscivorus'' (with the exception of a single hybrid from southern

Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

Ecology and natural history

Habitat

According to

Wright Wright is an occupational surname originating in England and Scotland. The term 'Wright' comes from the circa 700 AD Old English word 'wryhta' or 'wyrhta', meaning worker or shaper of wood. Later it became any occupational worker (for example, a ...

and

Bishop A bishop is an ordained member of the clergy who is entrusted with a position of Episcopal polity, authority and oversight in a religious institution. In Christianity, bishops are normally responsible for the governance and administration of di ...

(1915), in the

Okefenokee Swamp The Okefenokee Swamp is a shallow, 438,000-acre (177,000 ha), peat-filled wetland straddling the Georgia (U.S. state), Georgia–Florida line in the United States. A majority of the swamp is protected by the Okefenokee National Wildlife Ref ...

''A. conanti'' occurs in thickets along the edges of the cypress ponds of the islands, around the wooded edges of stretches of water, in areas where the woods of the islands meet pine woods, and throughout the swamp in general. In the

Everglades The Everglades is a natural region of flooded grasslands in the southern portion of the U.S. state of Florida, comprising the southern half of a large drainage basin within the Neotropical realm. The system begins near Orlando with the K ...

, Allen and Swindell (1948) mentioned that it can be found in palmetto clumps as much as a quarter mile from water. Otherwise these snakes tend to aggregate around drying water holes, most likely because of the increasing concentration of available prey. Duellman and

Schwartz Schwartz may refer to: * Schwartz (surname), a surname (and list of people with the name) * Schwartz (brand), a spice brand * Schwartz's, a delicatessen in Montreal, Quebec, Canada * Schwartz Publishing, an Australian publishing house *"Danny Schwa ...

(1958) described the species as inhabiting aquatic environments, cypress flats and wet prairies, but not pine forests, scrub or hammocks. The latter is contradicted by a report from northern Florida where large numbers were seen in wet pine-palmetto areas, except during very dry periods.

Reproduction

''Agkistrodon conanti'' is

ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a "bridging" form of reproduction between egg-laying oviparity, oviparous and live-bearing viviparity, viviparous reproduction. Ovoviviparous animals possess embryos that develo ...

, and while there is no specific mating season, most births occur during the summer months. Females generally only breed every other year and give birth to between one and 15 young per litter. The average total length of each newly born snake is .

Colloquialisms and folklore

Colloquial names for the Florida cottonmouth include aquatic copperhead, aquatic moccasin, cotton-mouthed snake, gaper, gapper, lake moccasin, mangrove rattler, moccasin viper, North American water viper, pond moccasin, river pit viper, short-tailed moccasin, small-tailed rattler, snap jaw, stub-tail moccasin, swamp lion, swamp moccasin, trap jaw, water mamba, water moccasin, water pilot, water pit moccasin, water rattlesnake, white mouth moccasin, and worm-tailed moccasin. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates, a Division of Cornell University Press. 1,105 pp. (in two volumes). ("Cottonmouth, Other common names", p. 916).

Gallery

File:Florida Water Moccasin 056.jpg, Florida cottonmouth (''Agkistrodon conanti)'' at the Cincinnati Zoo File:Agkistrodon piscivorus 7.jpg, Florida cottonmouth (''A. conanti)'' from Alachua County, Florida (23 March 2011) File:Agkistrodon piscivorus 6.jpg, Typical defensive display of a Florida cottonmouth (''A. conanti)'' from north-central Florida (9 April 2011)