Parts of a reptile

Amphibians and reptiles pdf

It presents a sexual dimorphism in which the male differs from the female especially because of its intensely colored skin, a characteristic that resembles the rocks covered by lichens that exist in its habitat.

It is precisely its dorsiventrally flattened, squat body that allows it, when it feels in danger, to assert itself among the rocks where it lives, expanding it for as long as necessary if someone tries to reach it in the middle of its narrow home.

Physical appearance: Solid body, squat, flattened dorsiventrally. The upper part of the body is grayish lead color and soft greenish tints in females to yellowish greenish especially males. Ventrally it is whitish gray.

5 names of reptiles

The Vertebrate Zoology Area includes the Divisions in charge of keeping and preserving specimens of fish, amphibians, reptiles, birds and mammals deposited at the Museo Argentino de Ciencias Naturales. Each collection is made up of specimens preserved by different techniques, whether they are complete animals or parts of them. Complete specimens, skeletons, skins and tissues are preserved in different ways, among which we can mention: taxidermization, alcohol, formalin and freezing.

The first specimens in these collections date back to the 19th century. At present, almost one hundred thousand specimens are deposited in the Area's collections. The Vertebrate Zoology Area is made up of the following Divisions: Ichthyology (Fishes), Herpetology (Amphibians and Reptiles), Ornithology (Birds) and Mastozoology (Mammals). Each of the Divisions has a Head and Researchers, Fellows and Technicians work in them. On the other hand, undergraduate and graduate students also actively participate in each of them, developing their theses and dissertations. As well as volunteers who actively collaborate with the research work and the maintenance of the collections. Each Division has a team of curators who are responsible, among other things, for the entry of the material, its identification and preservation. The research projects carried out are financed by research grants from the National Council for Scientific and Technical Research (CONICET), the National Agency for Scientific and Technological Promotion (ANPCyT) and numerous international organizations and foundations.

Guía de identificación de anfibios y reptiles de méxico

Los reptiles, como se definen comúnmente, son los animales de la clase Reptilia (/rɛpˈtɪliə/ rep-TIL-ee), un grupo parafilético que comprende todos los saurópsidos excepto las aves[1] Los reptiles vivos comprenden tortugas, cocodrilos, escamosos (lagartos y serpientes) y rinocéfalos (tuátaras). En marzo de 2022, la Base de Datos de Reptiles incluye unas 11.700 especies[2]. En el sistema tradicional de clasificación linneana, las aves se consideran una clase separada de los reptiles. Sin embargo, los cocodrilianos están más emparentados con las aves que con otros reptiles vivos, por lo que los sistemas modernos de clasificación cladística incluyen a las aves dentro de Reptilia, redefiniendo el término como un clado. Otras definiciones cladísticas abandonan el término reptil en favor del clado Sauropsida, que se refiere a todos los amniotas más emparentados con los reptiles modernos que con los mamíferos. El estudio de los órdenes tradicionales de reptiles, combinado históricamente con el de los anfibios modernos, se denomina herpetología.

Los primeros proto-reptiles conocidos se originaron hace unos 312 millones de años, durante el periodo Carbonífero, y evolucionaron a partir de tetrápodos reptiliomorfos avanzados que se fueron adaptando cada vez más a la vida en tierra firme. El primer euréptilo ("reptil verdadero") conocido fue Hylonomus, un animal pequeño y superficialmente parecido a un lagarto. Los datos genéticos y fósiles sostienen que los dos linajes más grandes de reptiles, Archosauromorpha (cocodrilos, aves y afines) y Lepidosauromorpha (lagartos y afines), divergieron hacia el final del periodo Pérmico[3]. Además de los reptiles vivos, hay muchos grupos diversos que ahora están extintos, en algunos casos debido a eventos de extinción masiva. En particular, la extinción del Cretácico-Paleógeno acabó con los pterosaurios, los plesiosaurios y todos los dinosaurios no avianos, junto con muchas especies de crocodiliformes y escamosos (por ejemplo, los mosasaurios). Los reptiles modernos no aviares habitan todos los continentes excepto la Antártida.

List of reptiles

Female Nile crocodiles lay their eggs in a buried nest, and open it when they hear squeaks coming from it. The sex of the hatchlings depends on the temperature of the nest, not genetics.Photo by Michael Nichols5 September 2010

The oceans, especially those that formed new, shallow inland, were teeming with abundant life. At the top of the food chain were long-necked plesiosaurs, giant marine crocodiles, sharks and rays. Fish-like ichthyosaurs, squid-like cephalopods and ammonoids with their spiral-shaped shells. Coral reefs grew in the warm waters and sponges, snails and mollusks grew without difficulty. Plankton floated free, microscopic and could make part of the ocean red.

On land, dinosaurs were making their mark, literally. The herbivorous sauropod Brachiosaurus stood 16 meters tall, was about 26 meters long and weighed more than 80 tons. Diplodocus, another sauropod, was about 27 meters long. The sheer size of these dinosaurs may have deterred the Allosaurus, a hulking, carnivorous dinosaur that walked on two powerful legs, from attacking them. But Allosaurus and other fleet-footed carnivores, such as coelurosaurs, might have been successful a time or two. Other prey could be the huge armored stegosaurs.