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Amphibians
Amphibia
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The AmphibiaWeb app provides mobile access to AmphibiaWeb and gives information about all amphibian species (frogs and toads, salamanders and newts, and caecilians), including pictures, sounds, as well as range maps and specimen collection points. The app will find all amphibians around one's current location, or, one can search for amphibians in any location around the world or by name. One can browse through the amphibians by name or image.
This app is based on data from AmphibiaWeb, an online system that provides access to information on amphibian declines, conservation, natural history, and taxonomy.
Range maps displayed derive from the IUCN Global Amphibian Assessment, 2010-2012.
An internet connection (wifi or cellular) is required.
App Developer, Mel Roderick
Available on iTunes:
https://itunes.apple.com/us/app/amphibiaweb/id476890286?mt=8
License | http://creativecommons.org/publicdomain/mark/1.0/ |
Rights holder/Author | Bnhmfs Apps, Bnhmfs Apps |
Source | http://amphibiaweb.org/about/mobile.html |
Amphibians around the world are rapidly disappearing. To conserve these fascinating creatures, scientists need your help!
License | http://creativecommons.org/publicdomain/mark/1.0/ |
Rights holder/Author | Katja Schulz, Katja Schulz |
Source | http://www.inaturalist.org/projects/global-amphibian-bioblitz |
Volunteers are needed to document the statewide distribution of Maryland’s amphibians and reptiles. The goal of the MARA project is to document the current distributions of Maryland’s amphibian and reptile species using a systematic and repeatable approach.
License | http://creativecommons.org/publicdomain/mark/1.0/ |
Rights holder/Author | Katja Schulz, Katja Schulz |
Source | http://www.marylandnature.org/mara/ |
NAAMP volunteers contribute their time to help states and USGS to assess frog and toad population trends. Data are collected using a calling survey technique, in which volunteers identify local amphibian species by their unique breeding vocalizations or calls.
Learn more about this project.
License | http://creativecommons.org/publicdomain/mark/1.0/ |
Rights holder/Author | Katja Schulz, Katja Schulz |
Source | http://www.pwrc.usgs.gov/naamp/ |
Amphibians are vertebrates of the taxonomic class Amphibia including animals such as frogs and toads (order Anura), salamanders (order Caudata), and caecilians (order Gymnophiona). Thought of as cold-blooded, amphibians are ectotherms, meaning they are unable to regulate their own body temperature independently of the temperature of their surroundings. Amphibians are generally small with thin skin permeable to air and water. With few exceptions, amphibians do not actively care for their young. In general, amphibian reproduction strategy consists of egg-laying and external fertilization of a large number of eggs in a moist or fully aquatic environment. Fertilized eggs develop into amphibian larvae that live part of their lives dependent on an aquatic environment requiring gills and specialized feeding habits. Following a pattern of development unique to amphibians, amphibian larvae undergo marked changes and metamorphose into a terrestrial form that lives on land. Typically, this metamorphosis is demonstrated by loss of gills, changes in overall appearance, and changes in diet.Amphibians live in diverse habitats, often in large numbers, and play several important ecological roles. As consumers, amphibians help regulate populations of the organisms they consume, chiefly invertebrates. As prey items, amphibians are consumed by a variety of larger predators such as reptiles, birds, mammals, fish, predatory invertebrates, and other amphibians. When consumed by larger predators, amphibians transfer the energy and nutrients from amphibian prey items such as small invertebrates to larger predators.
- National Biological Information Infrastructure (NBII) at http://www.nbii.gov
License | http://creativecommons.org/publicdomain/mark/1.0/ |
Rights holder/Author | Tracy Barbaro, Tracy Barbaro |
Source | http://www.nbii.gov/portal/server.pt/community/species_information/385 |
Salientia includes frogs and toads, and their close fossil relatives. The closest living relatives of the Salientia are the other amphibians, salamanders and caecilians. Frogs outnumber both of these groups substantially; as of May 2007, there are 172 living species of caecilians, 557 living salamanders, and 5424 living species of frogs.
The earliest known salientian is †Triadobatrachus massinoti, from the Early Triassic of Madagascar. This "proto-frog" is about 250 million years old. "Proto-frog" refers to the fact that it had not yet quite evolved the combination of features that are typically associated with frogs. For more information see †Triadobatrachus massinoti.
The earliest "true" frogs include †Prosalirus bitis and †Vieraella herbsti, from the Early Jurassic era. Thus, perfectly respectable frogs were around just before most of the major groups of dinosaurs had appeared. †Notobatrachus degiustoi from the Middle Jurassic is just a bit younger, about 155-170 million years old.
There are many distinctive features of living frogs. Frogs have at most nine vertebrae in front of the sacrum, and the three or four posterior to the sacrum are fused into a rod called the urostyle. In contrast, caecilians and salamanders have many more vertebrae and they do not have a urostyle. Frogs do not possess tails in the adult stage ("Anura" means without tail), as caecilians and salamanders do. Frogs also have a radioulna, which represents a fused radius and ulna (bones of the forearm), and a tibiofibula, the fused tibia and fibula (bones of the shank). The tibiale and fibulare (ankle bones; also called astragalus and calcaneum) of frogs are greatly elongate. Thus there is effectively an additional lever system that frogs can utilize in jumping. Indeed, the origin of saltation and its morphological correlates (lack of a tail, reduction in vertebrae, elongation of propulsive segments of the body) seems to be one of the features that clearly sets frogs apart from other major vertebrate groups (Gans and Parsons, 1966).
In addition to morphological distinctions, frogs also have a distinctive life phase known as the tadpole, which is a highly specialized "eating machine." Salamanders and caecilians have a larval form, but in neither does the larva possess the many specializations (such as the ceratohyal pump) that frog tadpoles have (Wassersug, 1974). Even the most basal living frogs have the beginnings of a unique mechanism of tongue projection (Nishikawa and Cannatella, 1991; Nishikawa and Roth, 1991) that is associated with extreme modification of the gill arches into a fused hyobranchial plate.
Although there is no scientific distinction between "frogs" and "toads", frogs are typically smooth-skinned, have long hind limbs for leaping, and live in water, while toads have warty, drier skin, with shorter hind limbs for hopping, and live on land (Halliday and Adler, 1986).
With so many species of frogs and toads, it is not surprising that they inhabit a wide variety of habitats. Habitat types range from arid desert regions to mountainous regions to swamps to tropical rainforests.
Temperature and water regulation are critical to frogs and toads, and amphibians in general. Being ectotherms, frogs and toads are reliant on the ambient temperature for body temperature regulation. In the winter months, frogs in temperate zones cannot remain active and must enter into a state of torpor, or extremely reduced activity. In the contrasting summer months, frogs can avoid the extreme heat by remaining underground in daylight, and being active at night (Halliday and Adler, 1986).
Salientians are also susceptible to the loss of body water due to extremely hot or dry conditions. Moisture regulation in frogs varies with their habitat. Those in temperate climates maintain moist skin to aid in evaporative cooling. As external air passes over the moist skin, the frog's body temperature is lowered. Additionally, permeable skin allows the frog the ability to absorb water simply by jumping into a pond or sitting in a puddle. Frogs in arid regions, on the other hand, have different ways of regulating body water. Their skin is often impermeable to water to prevent rapid evaporation and dehydration. Instead, they may cover their bodies with a thick mucus, or burrow to avoid the heat altogether.
Breeding in frogs is triggered by environmental cues such as temperature change and rainfall. During the breeding season (which varies with each species) hundreds or thousands of frogs may be seen in a congregation. Male frogs attract mates by calling; often many males call in chorus. Calling usually occurs near a body of water, such as a pond, where the eggs can be laid and fertilized. Egg masses may be laid in long chains or in large clumps. Parental care in frogs and toads is variable; some species lay many smaller eggs and have little parental care, while others lay a few larger eggs and remain with them until tadpoles or froglets develop.
License | http://creativecommons.org/licenses/by/3.0/ |
Rights holder/Author | David Cannatella, Tree of Life web project |
Source | http://tolweb.org/Salientia/14938 |
The amphibia include toads, frogs, caecilians, and salamanders. They are cold-blooded tetrapods, unlike most other tetrapods (they do not form an amnion). Most amphibian undergo metamorphosis from a juvenile water-breathing form (tadpoe) to an adult air-breathing form, but some retain the juvenile water-breathing form throughout life. Mudpuppies, for example, retain juvenile gills in adulthood. The three modern orders of amphibia: Anura (frogs and toads); Caudata (salamanders and newts); and Gymnophiona (caecilians, limbless amphibians that resemble snakes). There are about 6,500 species. Many amphibians lay their eggs in water. Amphibia superficially resembles reptiles, but reptiles are amniotes, and have surface scales. In the lasdt 20 or 30 years, there has been a dramatic decline in amphibian populations around the globe. Many species are now threatened or extinct. The earliest amphibia evolved in the Devonian period from lobe-finned fish that used their strong, bony fins to venture onto dry land. They were the top predators in the Carboniferous and Permian periods, but they later faced competition from their descendants, the reptiles, and many lineages were wiped out during the PermianâTriassic extinction. One group, the metoposaurs, remained important predators during the Triassic, but as the world became drier during the Early Jurassic they died out, leaving a handful of relict temnospondyls like Koolasuchus and the Lissamphibia.
The Salientia clade includes all frogs and toads from around the world. For a list of only the frog species found in Texas, as well as other amphibians and reptiles, see Herps of Texas
License | http://creativecommons.org/licenses/by/3.0/ |
Rights holder/Author | David Cannatella, Tree of Life web project |
Source | http://tolweb.org/Salientia/14938 |
The global distribution of Salientia is indicated in red.
License | http://creativecommons.org/licenses/by/3.0/ |
Rights holder/Author | David Cannatella, Tree of Life web project |
Source | http://tolweb.org/Salientia/14938 |
Females generally larger than males but males usually larger in species with male-male combat or paternal care.
License | http://creativecommons.org/publicdomain/zero/1.0/ |
Rights holder/Author | Fairbairn, 2013 |
Source | http://datadryad.org/resource/doi:10.5061/dryad.n48cm |