Green iguana ( Iguana iguana )
|Oppel , 1811|
The iguanas (Iguanidae) form a family of the squamata (squamata). They occur on the American double continent from the south of the USA to Paraguay , on the Caribbean Islands , the Galápagos Islands and the Fiji Islands.
Iguanas reach lengths of 14 centimeters up to two meters. The tail is often longer than the rest of the body. Their heads are often provided with scale combs or throat dewlaps, which are more pronounced in the males than in the females and are important in courtship and rivalry fights. The back scales of the lizards are usually small, the belly scales larger, but not in regular rows.
Way of life
They live terrestrially, on the ground ( Dipsosaurus , Cyclura ), on trees ( Iguana , Brachylophus ) or on rocks ( Sauromalus , Ctenosaura , Conolophus , Amblyrhynchus ). The males of most species of iguana are territorial. They defend their territory against other male conspecifics, but tolerate females. All iguanas lay eggs ( oviparous ). When mating, the male usually bites the female's neck. The clutches are often quite large, often several females lay their eggs close together. A brood care not take place.
Young animals feed mainly on insects and other invertebrates. Plant-based nutrition is becoming more and more important in adult animals, especially in the large species. The marine iguanas of the Galápagos Islands feed on algae and seaweed.
The systematics of the family is subjected since 1989 to frequent changes. During this time, the herpetologists Daryl Frost and Richard Etheridge divided the large family, then comprising 700 species, into a number of smaller families, which previously had the status of subfamilies. With the separated families, the iguanas are combined into the group of pleurodonts, which differ from the other iguanas known as acrodonts , the agamas and chameleons , by the type of tooth attachment. The common characteristic of the pleurodonts is teeth that are rootlessly located on the inner edge of the jaws, while the acrodonts are attached to the upper edge of the jaw.
Today eight recent and three extinct genera of iguanas are known:
- Iguanas (Iguanidae) Oppel, 1811
- Marine iguanas ( Amblyrhynchus cristatus ) (1 species)
- Fiji iguanas ( Brachylophus ) (4 species)
- Glandular heads ( Conolophus ) (3 species)
- Black iguanas ( Ctenosaura ) (15 species)
- Whorled tail iguanas ( Cyclura ) (8 species)
- Desert iguana ( Dipsosaurus dorsalis ) (1 species)
- Iguana (3 types)
- Chuckwallas ( Sauromalus ) (6 species)
- Armandisaurus (fossil)
- Lapitiguana (fossil)
- Pumila (fossil)
Marine iguanas ( Amblyrhynchus cristatus )
Fijian iguana ( Brachylophus fasciatus )
Glandular head ( Conolophus subcristatus )
Black iguana ( Ctenosaura similis )
( Cyclura cornuta )
Desert iguana ( Dipsosaurus dorsalis )
Green Island Guan ( Iguana delicatissima )
Chuckwalla ( Sauromalus obesus )
- Eric R. Pianka, Laurie J. Vitt: Lizards. Windows to the Evolution of Diversity (= Organisms and Environments. Vol. 5). University of California Press, Berkeley CA et al. a. 2003, ISBN 0-520-23401-4 .
- Manfred Rogner : Lizards. Keeping, care and breeding in the terrarium. Volume 1: geckos, pinnipeds, agamas, chameleons and iguanas. Ulmer, Stuttgart 1992, ISBN 3-8001-7248-8 .
- Rogner. 1992, p. 193.
- Iguanidae in The Reptile Database
- Pianka et al. 2003, p. 157.
- Darrel R. Frost, Richard Etheridge: A phylogenetic analysis and taxonomy of iguanian lizards (Reptilia: Squamata) (= University of Kansas. Museum of Natural History. Miscellaneous Publication. No. 81). University of Kansas, Lawrence KS 1989, ISBN 0-89338-033-4 .
- Darrel R. Frost, Richard Etheridge, Daniel Janies, Tom A. Titus: Total Evidence, Sequence Alignment, Evolution of Polychrotid Lizards, and a Reclassification of the Iguania (Squamata: Iguania) (= American Museum Novitates. No. 3343, online . ). American Museum of Natural History, New York NY 2001,