newt is an amphibian of the Salamandridae family, although not all aquatic salamanders are considered newts. Newts are classified in the subfamily Pleurodelinae of the family Salamandridae, and are found in North America, Europe and Asia. Aquatic larvae have true teeth on both upper and lower jaws, and external gills. They have the ability to regenerate limbs, eyes, spinal cords, hearts, intestines, and upper and lower jaws. The cells at the site of the injury have the ability to de-differentiate, reproduce rapidly, and differentiate again to create a new limb or organ. the male newt transfers a spermatophore which is taken up by the female. Fertilised eggs are laid singly and are usually attached to aquatic plants. This distinguishes them from the free-floating eggs of frogs or toads, that are laid in clumps or in strings.
Some species, such as the North American newts, also become more brightly coloured during this phase. Once fully metamorphosised they leave the water and live a terrestrial life, when they are known as "efts". Only when the eft reaches adulthood will the North American species return to live in water, rarely venturing back onto the land. More recently, a 29-year-old man in Coos Bay, Oregon, who had been drinking heavily, swallowed a rough-skin newt for a dare; he died later that day despite hospital treatment. However, the toxins are only dangerous if ingested, and the newts can easily and safely live in the same ponds or streams as frogs and other amphibians, or be safely kept as pets. The only predators of Taricha newts are garter snakes, some having developed a resistance to the poison. Most newts can be safely handled, provided that the toxins they produce are not ingested or allowed to come in contact with mucous membranes, or breaks in the skin. Other species present in Europe are the Iberian ribbed newt (Plurodeles waltl), which is the largest of the European newts the pyrenean brook newt (Calotriton sp.); the European brook newt (Euproctus sp.) and the Alpine newt (Mesotriton alpestris).
In North America, there are the Eastern newts (Notophthalmus spp.), of which the red-spotted newt (Notophthalmus viridescens) is the most abundant species, but it is limited to the area east of the Rocky Mountains.