FORS2355 Vertebrate Natural History
Survey Lab -- Class Amphibia
September 13, 2021
Predator Avoidance (aposematic, crypsis, camouflage) - Crypsis or camouflage is a strategy to avoid detection. If spotted by a predator, most amphibians will initially attempt escape (e.g., jumping). If this is not successful, the predator may hesitate to attack an amphibian that is aposematic (warning coloration) because that body pattern is indicative of toxic skin secretions. Some species reveal aposematic coloration by using an "unken" reflex that exposes a brightly colored ventral surface.
Locomotion (swimming/jumping/climbing/burrowing/gliding) - Structures associated with swimming, include lateral compression of the tail (e.g., newts) or webbed feet (e.g., ranid frogs). Jumping ability is positively correlated with the ratio of hind limb length - trunk length. Toads have pronounced tubercles on their hind feet that assist them in burrowing into the soil. Frogs with adhesive toepads (e.g., treefrogs) are good at climbing, and those with large, webbed fee are skilled at gliding.
Feeding Structures (jaw/teeth/tongue) - Blunt peg-like teeth are found in most amphibians (absent in true toads) to hold and/or crush prey. The tongue is used to manipulate prey - it is poorly developed and fully aquatic salamanders, but can be protrusible and/or sticky in frogs and terrestrial salamanders (esp. Plethodontidae). Amphibian larvae obtain their food by either scraping material (e.g., algae, detritus) from substrate, or filter-feeding in the water in the water column.
Integument (skin) - The skin is another primary respiratory surface for all amphibians and thus has relatively high vascularization. The skin contains mucous glands that keep the body surface moist, granular glands that secrete poison produced as an anti-predatory response and melanophores that can regulate color of skin
Respiratory Apparatus (gills) - Gills are present in all amphibian larvae and in paedomorphic or fully-aquatic salamander species. The gills may be exposed (many salamanders) or concealed in a ventral chamber (many frogs). These structures are replaced during metamorphosis by lungs for most species of salamanders and all frogs. Lungs also function to control buoyancy and can assist in anti-predatory behavior.
Ontogeny (development) - Most amphibians have 3 distinct life history stages: egg, larva, and adult. However, some species undergo direct development such that the young emerge from t he egg as miniature forms of the adult, with fully-formed legs and lungs. A few species of salamanders are paedomorphic, retaining larval characteristics (e.g., gills, caudal fins, etc.) even when they are reproductively mature adults
Species
Family
Order
Class
Subphylum
Three-toed Amphiuma
Amphiumidae
Caudata
Amphibia
Vertebrata
Hellbender
Cryptobranchida e
Caudata
Amphibia
Vertebrata
Gulf-Coast Waterdog
Proteidae
Caudata
Amphibia
Vertebrata
Lesser Siren
Sirenidae
Caudata
Amphibia
Vertebrata
Marbled Salamander
Ambystomatidae Caudata
Amphibia
Vertebrata
Mole Salamander
Ambystomatidae Caudata
Amphibia
Vertebrata
Small-Mouthed Salamander
Ambystomatidae Caudata
Amphibia
Vertebrata
Spotted Salamander
Ambystomatidae Caudata
Amphibia
Vertebrata
Tiger Salamander
Ambystomatidae Caudata
Amphibia
Vertebrata
Eastern Newt
Salamandridae
Caudata
Amphibia
Vertebrata
Dwarf Salamander
Plethodontidae
Caudata
Amphibia
Vertebrata
Slimy Salamander
Plethodontidae
Caudata
Amphibia
Vertebrata
Southern Dusky Plethodontidae Salamander
Caudata
Amphibia
Vertebrata
Couch's Spadefoot
Scaphiopodidae
Anura
Amphibia
Vertebrata
Hurter's Spadefoot
Scaphiopodidae
Anura
Amphibia
Vertebrata
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