Rainbow Lizard - Agama - A Fine Looking Little Fellow - An Illegal Immigrant at The Bay in Sarasota May 3, 2023

 

He is an illegal immigrant - an invasive species from Africa.

Agama agamaCommon Agama, Rainbow Lizard

By Ryan Hilgris

• Geographic Range
• Habitat
• Physical Description

• Reproduction
• Behavior
• Food Habits

• Conservation Status
• Contributors
• References

Ge­o­graphic Range

Found in most of sub-Sa­ha­ran Africa (Har­ris 1964).

• Biogeographic Regions
• Ethiopian 
   
  • native 

Habi­tat

Rain­bow lizards can oc­cupy urban, sub­ur­ban and wild areas that sup­ply enough veg­e­ta­tion for re­pro­duc­tion and in­sects for food.

• Terrestrial Biomes 
• desert or dune 
• savanna or grassland 
• forest 
• rainforest 
• scrub forest 
• mountains

Phys­i­cal De­scrip­tion

The agama lizard is char­ac­ter­ized by its whitish un­der­side, buff brown back limbs and tail with a slightly lighter stripe down the mid­dle and six to seven dark patches to the side of this stripe. There is some sex­ual di­mor­phism. The sub­or­di­nate males, fe­males, and ado­les­cents pos­sess an olive green head. A blue body and yel­low tail and head char­ac­ter­ize the dom­i­nant male. A. agama has a large head sep­a­rated from the body, a long tail, well-de­vel­oped ex­ter­nal ear open­ings and eye­lids. This lizard also has acrodont, het­erodont teeth. The lizard pos­sesses both canini­form in­cisors for grasp­ing and mo­lar­i­form cheek­teeth for crush­ing. The max­i­mum size for male lizards is twenty-five cen­time­ters and fe­male lizards is twenty cen­time­ters (Har­ris 1964).

Re­pro­duc­tion

Fe­males reach sex­ual ma­tu­rity at age four­teen to eigh­teen months, males at two years. A. agama re­pro­duces dur­ing the wet sea­son al­though they are ca­pa­ble of re­pro­duc­ing nearly year round in areas of con­sis­tant rain­fall(Porter et al. 1983). The male will ap­proach the fe­male from be­hind and head bob to her. If she ac­cepts then she will arch her back with her tail and head raised. The male walks to her side and grasps her neck and puts his leg on the fe­male's back, the pair swivel 90 de­grees in order to bring their cloa­cas to­gether and thrusts his tail onto her cloaca in­sert­ing his right or left hemipenes (de­pend­ing on side lo­ca­tion). This mat­ing rit­ual usu­ally lasts one to two min­utes when the fe­male will scurry away and the male also after sev­eral min­utes (Har­ris 1964).

The fe­male lays her eggs in a hole she digs with her snout and claws. The hole is five cen­time­ters deep and is found in sandy, wet, damp soil that is ex­posed to sun­light nearly all day and cov­ered by herbage or grasses. The eggs are usu­ally laid in clutches rang­ing from five to seven el­lip­soidal eggs. A. agama is a ther­moreg­u­lated em­bryo species re­sult­ing in all males at twenty-nine de­grees Cel­sius and all fe­males at twenty-six to twenty-seven de­grees Cel­sius (Crews et al. 1983). The eggs will hatch within eight to ten weeks. Hatch­lings will be be­tween 3.7 and 3.8 cen­time­ters snoutvent plus their 7.5-cen­time­ter tail. They will al­most im­me­di­ately start eat­ing rocks, sand, plants, and in­sects. The ado­les­cent will re­main soli­tary for the first two months and by four months live in a gre­gar­i­ous group with a dom­i­nant male (cock), sev­eral fe­males and some sub­or­di­nate ado­les­cent males (sub-males). The dom­i­nant male has mat­ing dis­tinc­tion within his ter­ri­tory. If a sub-male or in­truder tries to mate with his fe­males then there is a chal­lenge or fight. To gain ter­ri­tory males must es­tab­lish a new ter­ri­tory with no cocks or dis­pose of the cur­rent cock (Har­ris 1964).

Be­hav­ior

The agama is mostly a docile lizard ex­cept for a cock who de­fends his ter­ri­tory. There are sev­eral iden­ti­fi­able be­hav­iors in this species (head nod, head bob, chal­lenge dis­play, threat dis­play, fight­ing, and bask­ing). The head nod is when A. agama re­peat­edly raises and low­ers his head, usu­ally seen at the end of move­ments, pos­si­bly to show cock po­si­tion of in­di­vid­u­als. Head bob­bing, also known as push-ups, is the rais­ing and low­er­ing of the head and chest. This is done in an alert pos­ture, it also oc­curs in the re­pro­duc­tive be­hav­ior of the cock. Shown to fe­males when in re­pro­duc­tive col­ors, one to two be­gins courtship. The chal­lenge dis­play is shown by the cock to in­trud­ing males or sub-males show­ing re­pro­duc­tive color. This is only seen in ter­ri­tory sit­u­a­tions. The threat dis­play is the rapid up and down move­ment of the head with the gular sac fully ex­tended. The whole body raises and low­ers.

Dur­ing fight­ing males dis­play dif­fer­ent col­ors, usu­ally a dark brown head and a pale blue-grey gular pouch is dis­played to show in­ten­tion (Har­ris 1964). Fight­ing is a se­ries of bluffs, threats and com­bat. The chal­lenge oc­curs when a sub-male or in­trud­ing male of re­pro­duc­tion color comes into a ter­ri­tory. The res­i­dent cock will chal­lenge from a dis­play post show­ing the gular pouch while head bob­bing. The in­truder will react by re­treat­ing or stay­ing and dis­play­ing. If the in­truder stays then the cock will charge to within two feet and will change col­ors and threaten again, he will then rush within six inches and will side hop with mouth open. The males will then re­verse di­rec­tions and strike each other with their tails.

Bask­ing oc­curs mainly in the morn­ing be­tween ten and noon, when A. agama has a darker dor­sal col­oration than later in the day. The cock will have the best most el­e­vated site with the sub-males hav­ing the next best fol­lowed by the fe­males (Har­ris 1964).

Food Habits

Agama agama are pri­mar­ily in­sec­ti­vores, how­ever A. agama have been known to eat small mam­mals, small rep­tiles, and veg­e­ta­tion such as flow­ers, grasses, and fruits. Their diet con­sists of mainly ants, grasshop­pers, bee­tles, and ter­mites (Har­ris 1964). A. agama is a sit and wait preda­tor (Crews et al., 1983). Hunt­ing by vi­sion, it sits in veg­e­ta­tion, under a rock out­crop­ping, or in the shade and waits until an in­sect or small mam­mal walks by and then will chase the prey. They catch their prey by using a tongue with a tip cov­ered by mu­cous glands; this aids the lizard in hold­ing onto small prey such as ants and ter­mites.

Con­ser­va­tion Sta­tus

• IUCN Red List

  No special status
  More information

Con­trib­u­tors

Ryan Hilgris (au­thor), Michi­gan State Uni­ver­sity, James Hard­ing (ed­i­tor), Michi­gan State Uni­ver­sity.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

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

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.

scrub forest

scrub forests develop in areas that experience dry seasons.

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.

Ref­er­ences

Crews, D., Gustafson, J.E., Tokarz, R.R.. 1983. Physco­bi­ol­ogy of Parthno­gen­e­sis. Pp. 205-232 in R Huey, E Pi­anka, T Schoener, eds. Lizard Ecol­ogy. Stud­ies of a Model Or­gan­ism.. Cam­bridge, Mass. and Lon­don, Eng­land: Har­vard Uni­ver­sity Press.

Har­ris, V. 1964. The Life of the Rain­bow Lizard. Lon­don, Eng­land: Hutchin­son Trop­i­cal Mono­graphs.

Porter, W., C. Tracy. 1983. Bio­phys­i­cal Analy­sis of En­er­get­ics, Time-Space Uti­liza­tion, and Dis­tri­b­u­tional Lim­its. Pp. 55-83 in R Huey, E Pi­anka, T Schoener, eds. Lizard Ecol­ogy. Stud­ies of a Model Or­gan­ism.. Cam­bridge, Mass. and Lon­don, Eng­land: Har­vard Uni­ver­sity Press.

Regal, P. 1983. The Adap­tive Zone Be­hav­ior of Lizards. Pp. 105-118 in R Huey, E Pi­anka, T Schoener, eds. Lizard Ecol­ogy. Stud­ies of a Model Or­gan­ism. Cam­bridge, Mass. and Lon­don, Eng­land: Har­vard Uni­ver­sity Press.

Simon, C. 1983. A Re­view of Lizard Chemore­cep­tion.. Pp. 119-133 in R Huey, E Pi­anka, T Schoener, eds. Lizard Ecol­ogy. Stud­ies in a Model Or­gan­ism.. Cam­bridge, Mass. and Lon­don, Eng­land: Har­vard Uni­ver­sity Press.

Stamps, J. 1983. Sex­ual Se­lec­tion, Sex­ual Di­mor­phism, and Ter­ri­to­ri­al­ity. Pp. 169-204 in R Huey, E Pi­anka, T Schoener, eds. Lizard Ecol­ogy. Stud­ies in a Model Or­gan­ism.. Cam­bridge, Mass. and Lon­don, Eng­land: Har­vard Uni­ver­sity Press.