Ameiva ameivaGiant Ameiva, Amazon Racerunner

Last updated:

Geographic Range

Giant ameivas are found in Central and South America. They are found from the eastern coast of Brazil through the interior portions of central South America, to the west coasts of Columbia, Ecuador, and Peru. They are found as far south as the northern portions of Argentina, through Bolivia and Paraguay and as far north as French Guiana, Suriname, Guyana, Trinidad, Tobago, and Panama. Recently they have been introduced to areas of Florida. ("Scientific and Standard English Names", 2001; Biazquez, 1996; Sartorius, et al., 1999)

Habitat

Giant ameivas are found in varied habitats, such as cerrado and northeastern caatinga in Brazil and Amazonian savannah and forests. They seem to prefer disturbed rain forests that have recently been harvested. (Biazquez, 1996; Colli, 1991)

Physical Description

Giant ameivas are medium-sized lizards with a body mass of about 60 g and a typical snout to vent length of 120 to 130 mm. Snout-vent lengths have been recorded as high as 160 mm in females and 180 mm in males. Cranial width averages 18 mm. Giant ameivas have femoral pores on the ventral side of the hind legs. Pore size is similar in both males and females, at about 1 mm in diameter. However, males have a single row of pores, about 17 to 23, running down the leg, whereas females have 16 to 22. Femoral pores are easy to see and the scales that hold them are specialized. This specialization helps in identifying the difference between those and other scales in the surrounding area of the hind leg. The rest of their body is covered with smooth scales. Coloration in both males and females is the same. However, juveniles differ in color from adults. Their backs have lines running the length of their body, colored yellow in adults and white in juveniles. Apart from these lines covering the dorsal portions of their body, the rest of their coloring is a dark brown. Their ventral side is ivory. (Biazquez, 1996; Colli, 1991; Imparato, et al., 2007; Sartorius, et al., 1999; Vitt, 1991)

  • Sexual Dimorphism
  • male larger
  • Average mass
    68 g
    2.40 oz
  • Range length
    180 (high) mm
    7.09 (high) in
  • Average length
    125 mm
    4.92 in

Development

Females carry their eggs for a short period of time and tend to stay in their burrows during this time. Once eggs are laid, incubation time is about 5 months, with offspring usually hatching at the beginning of the rainy season. Juvenile males tend to grow faster than their female counterparts. Maturity is acheived when snout-vent length reaches 100 mm, occurring at about 8 months after hatching for both males and females. (Colli, 1991; Vitt, 1982; Vitt, 1991)

Reproduction

There is little information on mating systems of Ameiva ameiva. The Ameiva plei mating system has been observed. This species is similiar to Ameiva ameiva in size and the environments in which they live, so their reproductive biology may be similar. Ameiva plei males tend to guard females during sexual encounters. However, males that did not guard females did not mate. Males in this species that were larger tended to mate more as they won over the most females.

Giant ameivas reproduce by laying eggs in clutches, which vary in size regionally. Although little data exist from most regions, data have been collected from caatinga and cerrado habitats of Brazil. Clutch size can range from 3 to 11. Clutch sizes tend to be larger in cerrado, averaging 6.4 +/- 0.2 (Colli, 1991). Clutch sizes in caatinga average 5.7 +/- 0.164 (Vitt, 1982). Clutch size is directly related to snout-vent length of the female - larger females produce more eggs per clutch. In cerrado, females can lay up to 3 clutches per reproductive season. However, in caatinga giant ameivas may reproduce throughout the year. The reproductive habits of Ameiva ameiva are based on rainfall. In areas where rainfall is constant or unpredictable throughout the year, reproduction is year-round. In areas where there is a distinct dry season, reproduction only occurs during the rainy seasons. This is thought to be the result of lack of food for both adults and juveniles during dry seasons. (Colli, 1991; Vitt, 1982)

  • Breeding interval
    Breeding interval is based on location however females may lay up to 3 clutches per cycle in the Cerrado of Brazil.
  • Breeding season
    Breeding seasons are based on environment.
  • Average number of offspring
    6
  • Average gestation period
    5 months
  • Average age at sexual or reproductive maturity (female)
    8 months
  • Average age at sexual or reproductive maturity (male)
    8 months

There is little information on parental investment in this species. However, females invest heavily in supplying their eggs with nutrients before they are laid and males invest energy in mate guarding during mating.

  • Parental Investment
  • no parental involvement
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female

Lifespan/Longevity

No data exist about the lifespan of Ameiva ameiva in the wild. However, based on small sample sizes, individuals are known survive up to 4.6 years. The Index of Scientific Binomials indicate their observed specimen lived up to 2.8 years in captivity. ("Index of Scientific Binominals", 2002; Bowler, 1975)

  • Typical lifespan
    Status: captivity
    2.8 to 4.6 years

Behavior

Giant ameivas are solitary and diurnal. Not much is known about their behavior.

Home Range

Giant ameivas are not territorial. However, they do have a home range which overlaps with other individuals. Data are not available for home range size of Ameiva ameiva. In a similar species, Lewis and Saliva (1987) report that the home range size of Ameiva exsul is based on size and sex of the lizard. Average male home range size was 376.8 square meters, and female home range was on average 173.7 square meters based on a data set from 13 males and females. Home range size may be similar in Ameiva ameiva. (Lewis and Saliva, 1987; Simmons, et al., 2005)

Communication and Perception

Femoral glands located on the ventral underside of the hind legs of Ameiva ameiva play a role in establishing territory size. Femoral glands also play a role in various sexual behaviors. These femoral glands produce semiochemicals which influence inter- and intra-specific communication. Although these semiochemicals are not well understood in Ameiva ameiva, they affect defense of territory and self, predation, territorial markings, and parental care. (Imparato, et al., 2007; Imparato, et al., 2007)

Food Habits

Giant ameivas are active foragers. Their diet varies regionally and seasonally and consists mainly of insects. The most common animals found in their diet are grasshoppers, butterflies, beetles, roaches, larvae, spiders, and termites. They have also been known to eat other species of lizards. What they eat is proportional to their snout-vent length; as they grow their prey becomes larger. (Magnusson, 1987; Boyden, 1976; Magnusson, 1987)

  • Animal Foods
  • reptiles
  • insects
  • terrestrial non-insect arthropods

Predation

Predators of giant ameivas consist of a wide variety of birds and snakes. Unlike other species of lizards found throughout South America, they do not sit and wait for their prey. Their main method of avoiding predation is escape and their body shape is designed for rapid speed, allowing them to avoid predators in the open areas where they forage. Common predators of Ameiva ameiva include green snakes (Philodryas nattereri), roadside hawks (Buteo magnirostris), American kestrels (Falco sparverius), Guira cuckoos (Guira guira), chalk-browed mockingbirds (Mimus satturninus) and coral snakes (Micrurus frontalis). Giant ameivas are poorly adapted to introduced predators, such as mongooses (Herpestes javanicus) and house cats (Felis catus). (Colli, 1991; Maffei, et al., 2009; Shepard, 2007)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Giant ameivas are hosts for a wide variety of microorganisms. Common parasites include Plasmodium tropidury, Lainsonia, Hemolivia petit, Choleoeimeria carinii, Acroeimeria pintoi, and Isospora ameiva. Often these invasive parasites will damage organs such as the gall bladder, liver, kidneys, lungs, and spleen. Parasites also have been found in saliva and feces of this lizard. Many of the parasites found in the feces originate in the gut. Additionally, parasites invade epithelial cells. (Kaplan, 1995; Lainson and Paperna, 1999; Lainson, et al., 2003)

Commensal/Parasitic Species
  • Plasmodium tropidury
  • Lainsonia
  • Hemolivia petit
  • Choleoeimeria carinii
  • Acroeimeria pintoi
  • Isospora ameiva

Economic Importance for Humans: Positive

Although these species can carry disease and can be aggressive, people keep them as pets. Furthermore, giant ameivas tend to prefer cleared environments such as crop fields. Because their diet consists mainly of arthropods, they can help to keep pest populations under control. (Everard, et al., 1979; Kaplan, 1995; Sartorius, et al., 1999)

  • Positive Impacts
  • pet trade
  • controls pest population

Economic Importance for Humans: Negative

Giant ameivas are known carriers of the bacteria Salmonella, including strains that can infect humans. In Grenada, according to Everard et al. (1979), half of all specimens collected carried Salmonella. In Panama, giant ameivas had the highest percentage occurrence of Salmonella of all 447 specimens examined (Kournay, 1981). (Everard, et al., 1979; Kourany and Telford, 1981)

Conservation Status

Currently giant ameivas are not considered threatened. There are no efforts at this time to actively conserve this species.

Contributors

Ryan Siders (author), Radford University, Karen Powers (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

carnivore

an animal that mainly eats meat

causes or carries domestic animal disease

either directly causes, or indirectly transmits, a disease to a domestic animal

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

insectivore

An animal that eats mainly insects or spiders.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

year-round breeding

breeding takes place throughout the year

References

"AnAge entry for Ameiva ameiva" (On-line). Accessed April 09, 2010 at http://genomics.senescence.info/species/entry.php?species=Ameiva_ameiva.

2002. "Index of Scientific Binominals" (On-line). Accessed April 09, 2010 at http://www.demogr.mpg.de/longevityrecords/index1.htm.

"Occurrence Overview" (On-line). Global Biodiversity Information Facility. Accessed February 19, 2010 at http://data.gbif.org/species/13500252/.

Committee on Standard English and Scientific Names. Scientific and Standard English Names. Society for the Study of Amphibians and Reptiles. 2001. Accessed February 19, 2010 at http://www.ssarherps.org/pdf/Crother.pdf.

Biazquez, M. 1996. Activity and Habitat Use in a Population of Ameiva ameiva in Southeastern Columbia. Biotropica, 28 (4): 714-719. Accessed February 04, 2010 at http://www.jstor.org/stable/pdfplus/2389057.pdf.

Bowler, J. 1975. Longevity of Reptiles and Amphibians in N. American Collections as of 1 November, 1975.. Herpetological Circular, 6: 1-32.

Boyden, T. 1976. Butterfly Palatability and Mimicry: Experiment with Ameiva Lizards. Evolution, 30: 73-81. Accessed February 03, 2010 at http://www.jstor.org/stable/2407673.

Censky, E. 1995. Mating Strategy and Reproduction Success in the Teiid Lizard, Ameiva. Behaviour, 132 (7/8): 529-557.

Colli, G. 1991. Reproductive Ecology of Ameiva ameiva (Sauria, Teiidae) in the Cerrado of Central Brazil. Copeia, 4: 1002-1012. Accessed February 03, 2010 at http://www.jstor.org/stable/1446095?seq=1.

Everard, C., B. Tota, D. Bassett, C. Ali. 1979. Salmonella in Wildlife from Trinidad and Grenada, W.I.. Journal of Wildlife Diseases, 15: 213-219. Accessed April 09, 2010 at http://www.jwildlifedis.org/cgi/reprint/15/2/213.

Giugliano, L., R. Teixeira, G. Colli, S. Bao. 2002. Ultrastructure of Spermatozoa of the Lizard Ameiva ameiva, With Considerations on Polymorphism Within the Family Teiidae (Squamata). Journal of Morphology, 253: 264-271. Accessed February 04, 2010 at http://www3.interscience.wiley.com/cgi-bin/fulltext/94518856/PDFSTART.

Imparato, B., M. Antoniazzi, M. Rodrigues, C. Jared. 2007. Morphology of the Femoral Glands in the Lizard Ameiva ameiva (Teiidae) and Their Possible Role in Semiochemical Dispersion. Journal of Morphology, 268: 636-648. Accessed February 19, 2010 at http://www.biota.org.br/publi/banco/docs/27996_1211224237.pdf.

Kaplan, M. 1995. "Ameivas" (On-line). Accessed April 09, 2010 at http://www.anapsid.org/ameiva.html.

Kourany, M., S. Telford. 1981. Lizards in the Ecology of Salmonellosis in Panama. Applied and Environmental Microbiology, 41(5): 1248-1253. Accessed April 09, 2010 at http://aem.asm.org/cgi/reprint/41/5/1248.

Lainson, R., I. Paperna. 1999. Some Coccida from the Gall-Bladder and Intestine of the Teiid Lizard Ameiva Ameiva ameiva and the gecko HEMIDACTYLUS MABOUIA IN NORTH BRAZIL. Parasite, 6: 151-162. Accessed April 09, 2010 at http://iah.iec.pa.gov.br/iah/fulltext/pc/artigos/1999/parasite1999v6p151-162.pdf.

Lainson, R., M. Souza, C. Franco. 2003. Haematozoan Parasites of the Lizard Ameiva ameiva (Teiidae) from Amazonian Brazil: a Preliminary Note. Memorias do Instituto Oswaldo Cruz, 98(8): 1067-1070. Accessed April 09, 2010 at http://www.scielo.br/pdf/mioc/v98n8/v98n8a16.pdf.

Lewis, A., J. Saliva. 1987. Effects of Sex and Size on Home Range, Dominance, and Activity Budgets in Ameiva Exsul (Lacertilia: Teiida). Herpetologica, 43(3): 374-383.

Maffei, F., G. Rodrigues do Nascimento, D. Neto. 2009. Predation on the lizard Ameiva ameiva (Sauria: Teiidae) by a coral snake Micrurus frontalis (Serpentes: Elapidae) in Brazil. Herpetology Notes, 2: 235-237. Accessed February 05, 2010 at http://www.seh-herpetology.org/herpetologynotes/Volume2_PDFs/Maffei_Herpetology_Notes_Volume2_pages235-237.pdf.

Magnusson, W. 1987. Reproductive Cycles of Teiid Lizards in Amazonian Savanna. Journal of Herpetology, 21: 307-316. Accessed February 04, 2010 at http://www.jstor.org/stable/1563972.

Magnusson, W., L. Junqueira de Paiva, R. Moreira da Rocha, C. Franke, L. Kasper, A. Lima. 1985. The Correlates of Foraging Mode in a Community of Brazilian Lizards. Herpetologica, 41(3): 324-332. Accessed March 10, 2010 at http://www.jstor.org/stable/pdfplus/3892278.pdf.

Magnusson, W., L. Junqueira de Paiva, R. Moreira da Rocha, C. Franke, L. Kasper, A. Lima. 1985. THE CORRELATES OF FORAGING MODE IN A COMMUNITY OF BRAZILIAN LIZARDS. Herpetologica, 41: 324-332. Accessed February 05, 2010 at http://www.jstor.org/stable/3892278.

McCRYSTAL, H., J. Behler. 2007. Husbandry and reproduction of captive Giant ameiva I lizards Ameiva ameiva at the New York Zoological Park. International Zoo Yearbook, 22: 159-163. Accessed February 04, 2010 at http://www3.interscience.wiley.com/cgi-bin/fulltext/119560147/PDFSTART.

Sartorius, S., L. Vitt, G. Colli. 1999. Use of naturally and anthropogenically disturbed habitats in Amazonian rainforest by the teiid lizard Ameiva ameiva. Biological Conservation, 90: 91-101. Accessed February 01, 2010 at http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6V5X-3WK3D1K-1-W&_cdi=5798&_user=768496&_pii=S0006320799000191&_orig=search&_coverDate=09%2F30%2F1999&_sk=999099997&view=c&wchp=dGLzVzz-zSkWA&md5=912724075efac1886a88a046583b842a&ie=/sdarticle.pdf.

Sevenster, J., J. Ellers, G. Driessen. 1998. An Evolutionary Argument for Limitation. Evolution, 52: 1241-1244. Accessed February 04, 2010 at http://www.jstor.org/stable/2411256.

Shepard, D. 2007. Habitat but not body shape affects predator attack frequency on lizard models in the Brazilian Cerrado. Herpetologica, 63(2): 193-202. Accessed March 10, 2010 at http://www.bioone.org/doi/pdf/10.1655/0018-0831%282007%2963%5B193%3AHBNBSA%5D2.0.CO%3B2.

Simmons, J. 1975. The Female Reproductive Cycle of the Teiid Lizard Ameiva ameiva Petersii Cope. Herpetologica, 31: 297-282. Accessed February 03, 2010 at http://www.jstor.org/stable/3891588.

Simmons, P., B. Greene, K. Williamson, R. Powell, J. Parmerlee. 2005. Ecological Interactions Within a Lizard Community on Grenada. Herpetologica, 61(2): 124-134.

Smith, R. 1968. Experimental Evidence for a Gonadal-Fat Bpdy Relationship in Two Teiid Lizards (Ameiva festive>, <<Ameiva Quadrilineata). Biological Bulletin, 134: 325-331. Accessed February 04, 2010 at http://www.jstor.org/stable/1539608.

Tinkle, D. 1969. The Concept of Reproduction Effort and its Relation to the Evolution of Life Histories of Lizards. The American Naturalist, 103: 501-516. Accessed February 04, 2010 at http://www.jstor.org/stable/2459411?seq=1.

Vitt, L. 1991. An Introduction to the Ecology of Cerrado Lizards. Journal of Herpetology, 25: 79-90. Accessed February 19, 2010 at http://www.jstor.org/stable/pdfplus/1564798.pdf.

Vitt, L. 1982. Reproductive tactics of Ameiva ameiva (Lacertilia: Teiidae) in a seasonally fluctuating tropical habitat. Canadian Journal of Zoology, 60: 3113-3120.