''Lithobates pipiens''Integrated Taxonomic Information System nternet2012
''Lithobates pipiens''
pdated 2012 Sept; cited 2012 Dec 26Available from: www.itis.gov/ formerly ''Rana pipiens'', commonly known as the northern leopard frog, 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), ...

leopard frog Leopard frog is a generic name used to refer to various species in the true frog genus Lithobates. They all have similar coloration: brown or green with spots that form a leopard pattern. They are distinguished by their distribution and behaviora ...

from the

true frog True frogs is the common name for the frog family (biology), family Ranidae. They have the widest distribution of any frog family. They are abundant throughout most of the world, occurring on all continents except Antarctica. The true frogs are p ...

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 ...

, native to parts of

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

and the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. It is the

state amphibian This is a list of official U.S. state, federal district, and territory amphibians. State amphibians are designated by tradition or the respective State legislature (United States), state legislatures.Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

and

Vermont Vermont () is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York (state), New York to the west, and the Provinces and territories of Ca ...

Description

The northern leopard frog is a fairly large species of frog, reaching about in snout-to-vent length. It varies from green to brown in

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

color, with large, dark, circular spots on its back, sides, and legs.Northern Leopard Frog ''Rana pipiens''
National Geographic. Retrieved 2015-03-28 Each spot is normally bordered by a lighter ring. A pair of dorsolateral folds starting from the back of the eye runs parallel to each other down the back. These dorsolateral folds are often lighter or occasionally pinkish in colour. Also, a pale stripe runs from the nostril, under the eye and tympanum, terminating at the shoulder. The

ventral Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

surface is white or pale green. The iris is golden and toes are webbed.

Tadpole A tadpole or polliwog (also spelled pollywog) is the Larva, larval stage in the biological life cycle of an amphibian. Most tadpoles are fully Aquatic animal, aquatic, though some species of amphibians have tadpoles that are terrestrial animal, ...

s are dark brown or grey, with light blotches on the underside. The tail is pale tan.

Color variations

The northern leopard frog has several different color variations, with the most common two being the green and the brown morphs, with another morph known as the burnsi morph. Individuals with the burnsi morph coloration lack spots on their backs, but may or may not retain them on their legs. They can be bright green or brown and have yellow dorsal folds. Albinism also appears in this species, but is very rare. They can also be blue, and this is quite rare also.

Ecology and behavior

Northern leopard frogs have a wide range of habitats. They are found in permanent ponds, swamps, marshes, and slow-moving streams throughout forest, open, and urban areas.Northern Leopard Frog (''Lithobates pipiens'')
Nevada Fish and Wildlife Office. Retrieved 2015-03-28. They normally inhabit water bodies with abundant aquatic vegetation. In the summer, they often abandon ponds and move to grassy areas and lawns. They are well adapted to cold and can be found above

above mean sea level Height above mean sea level is a measure of a location's vertical distance (height, elevation or altitude) in reference to a vertical datum based on a historic mean sea level. In geodesy, it is formalized as orthometric height. The zero level ...

. Males make a short, snore-like call from water during spring and summer. The northern leopard frog breeds in the spring (March–June). Up to 6500 eggs are laid in water, and tadpoles complete development within the breeding pond. Tadpoles are light brown with black spots, and development takes 70–110 days, depending on conditions. Metamorph frogs are long and resemble the adult. This species was once quite common through parts of western Canada and the United States until declines started occurring during the 1970s. Although the definitive cause of this decline is unknown, habitat loss and fragmentation, environmental contaminants, introduced fish, drought, and disease have been proposed as mechanisms of decline and are likely preventing species' recovery in many areas. Many populations of northern leopard frogs have not yet recovered from these declines. Northern leopard frogs are preyed upon by many different animals, such as

snake Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...

s, other

frog A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough ski ...

s, and even

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

s. They do not produce distasteful skin secretions and rely on speed to evade predation. They eat a wide variety of animals, including crickets, flies, worms, and smaller frogs. Using their large mouths, they can even swallow birds and garter snakes. In one case, a

bat Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...

was recorded as prey of this frog. This species is similar to the

pickerel frog The pickerel frog (''Lithobates palustris'', formerly ''Rana palustris'') is a small North American frog, characterized by the appearance of seemingly "hand-drawn" squares on its dorsal surface. Distinguishing features The pickerel frog is a me ...

(''Lithobates palustris'') and the

southern leopard frog ''Lithobates sphenocephalus'' or ''Rana sphenocephala'', commonly known as the southern leopard frog, is a medium-sized anuran in the family Ranidae (the true frogs). The southern leopard frog is one of the 36 species currently or formerly classi ...

(''Lithobates sphenocephalus'').

Research

Medical

The northern leopard frog produces specific

ribonuclease Ribonuclease (commonly abbreviated RNase) is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within th ...

s to its

oocyte An oocyte (, oöcyte, or ovocyte) is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ger ...

s. Those enzymes are potential drugs for

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

. One such molecule, called

ranpirnase Ranpirnase is a ribonuclease enzyme found in the oocytes of the Northern Leopard Frog (''Rana pipiens''). Ranpirnase is a member of the pancreatic ribonuclease (RNase A) protein superfamily and degrades RNA substrates with a sequence preference ...

(onconase), is in clinical trials as a treatment for

pleural The pleural cavity, or pleural space (or sometimes intrapleural space), is the potential space between the pulmonary pleurae, pleurae of the pleural sac that surrounds each lung. A small amount of serous fluid, serous pleural fluid is maintained ...

mesothelioma and

lung The lungs are the primary Organ (biology), organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the Vertebral column, backbone on either side of the heart. Their ...

tumors. Another, amphinase, has been described as a potential treatment for

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

tumors.

Neuroscience

The northern leopard frog has been a preferred species for making discoveries about basic properties of

neurons A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...

since the 1950s. The

neuromuscular junction A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. Muscles require innervation to ...

of the

sciatic nerve The sciatic nerve, also called the ischiadic nerve, is a large nerve in humans and other vertebrate animals. It is the largest branch of the sacral plexus and runs alongside the hip joint and down the right lower limb. It is the longest and widest ...

fibers of the

sartorius muscle The sartorius muscle () is the longest muscle in the human body. It is a long, thin, superficial muscle that runs down the length of the thigh in the anterior compartment. Structure The sartorius muscle originates from the anterior superior ilia ...

of this frog has been the source of initial data about the

nervous system In biology, the nervous system is the complex system, highly complex part of an animal that coordinates its behavior, actions and sense, sensory information by transmitting action potential, signals to and from different parts of its body. Th ...

Muscle physiology and biomechanics

The northern leopard frog is a popular species for ''

in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...

'' experiments in

muscle Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...

physiology and

biomechanics Biomechanics is the study of the structure, function and motion of the mechanical aspects of biological systems, at any level from whole organisms to Organ (anatomy), organs, Cell (biology), cells and cell organelles, using the methods of mechani ...

due to the ease of accessibility for investigators in its native range and the ability of the

to stay alive ''in vitro'' for several hours. Furthermore, the reliance of the frog on two major modes of locomotion (

jumping Jumping or leaping is a form of locomotion or movement in which an organism or non-living (e.g., robotic) mechanical system propels itself through the air along a ballistic trajectory. Jumping can be distinguished from running, galloping and ...

and

swimming Swimming is the self-propulsion of a person through water, such as saltwater or freshwater environments, usually for recreation, sport, exercise, or survival. Swimmers achieve locomotion by coordinating limb and body movements to achieve hydrody ...

) allows for understanding how muscle properties contribute to organismal performance in each of these modes.

Range

Northern leopard frogs occur from

Great Slave Lake Great Slave Lake is the second-largest lake in the Northwest Territories, Canada (after Great Bear Lake), List of lakes by depth, the deepest lake in North America at , and the List of lakes by area, tenth-largest lake in the world by area. It ...

and

Hudson Bay Hudson Bay, sometimes called Hudson's Bay (usually historically), is a large body of Saline water, saltwater in northeastern Canada with a surface area of . It is located north of Ontario, west of Quebec, northeast of Manitoba, and southeast o ...

, Canada, south to

Kentucky Kentucky (, ), officially the Commonwealth of Kentucky, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the ...

and

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

, USA.Conant, R. and Collins, J.T. (1991). ''A Field Guide to Reptiles and Amphibians: Eastern and Central North America.'' Third Edition. Houghton Mifflin Company, Boston, Massachusetts. It is also found in

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, where it is endemic to the central cordillera and western Pacific lowlands, although this is most likely an undescribed species. They occupy grasslands, lakeshores, and marshes.

References

External links

* *
Northern Leopard Frog (''Rana pipiens'')
— ''Natural Resources Canada''.

— ''animal diversity, University of Michigan''.
BBC news: "''Rana pipiens'' and the treatment of brain tumours."
{{Authority control Lithobates Amphibians of the United States Amphibians of Canada Fauna of the Great Lakes region (North America) Fauna of the Eastern United States Fauna of the Plains-Midwest (United States) Animal models Amphibians described in 1782 Symbols of Minnesota Symbols of Vermont