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Last updated on April 18, 2014 at 10:16 EDT

Eastern Newt, Notophthalamus viridescens

The Eastern Newt (Notophthalamus viridescens) is a common newt of eastern North America. They frequent small lakes, ponds, and streams or near-by wet forests. They can coexist in an aquatic environment with small, noncarnivorous fish, as their skin secretes a poisonous substance when the newt is threatened or injured. They have lifespans of 12 to 15 years within the wild and may grow to five inches long. These newts are common aquarium pets, being either collected from the wild or bought. The strikingly colored juvenile stage, which is land-dwelling, is often known as the red eft. Some sources blend the general name of the species and Red-spotted Newt subspecies name into Eastern Red-spotted Newt.

This species as four subspecies, the Red-spotted Newt (N. v. viridescens), the Broken-striped Newt (N. v. dorsalis), the Central Newt (N. v. louisianensis) and the Peninsula Newt (N. v. piaropicola).

These eastern newts have three stages of their life, the aquatic larva or tadpole stage, the red eft or terrestrial juvenile stage, and the aquatic adult stage.

The larva possesses gills and doesn’t leave the pond environment where it was hatched. Larvae are brown-green and shed their gills when they transform into the red eft.

The red eft is bright orangeish red in coloration, with darker red spots outlined in black. As eastern newt can have as many as 21 spots. The pattern of these differs among the subspecies. During this stage in their life, the eft may travel far, acting as a dispersal stage from one pond to another, ensuring outcrossing in the population.

After two or three years, the eft finds a pond and transforms into the aquatic adult. The skin of the adult is olive green, but retains the efts characteristic outlined red spots. It has a larger and wider tail and slimy skin.

It’s common for the Peninsula Newt (N. v. piaropicola) to be neotenic, with a larva transforming directly into a sexually mature aquatic adult, never losing the external gills. The red eft stage is, in these cases, skipped.

The Eastern Newts home using magnetic orientation. Their magnetoreception system appears to be a hybrid of polarity-based inclination and sun-dependent compass. Ferromagnetic material, most likely biogenic magnetite, is likely present in the Eastern Newts body.

These newts are at home in both coniferous and deciduous forests. They require a moist environment with either a temporary or permanent body of water, and thrive best in a muddy environment. During the eft stage, they may travel far from their initial location. Red efts may frequently be seen in a forest after a rainstorm. The adult show a preference for muddy habitat, but will move to land during a dry spell. They have some amount of toxins in their skin, which is brightly colored to act as a warning. Even then, only 2 percent of larvae make it to the eft stage. Some larvae have been found in the pitchers of the carnivorous plant Sarracenis purpurea.

They consume a variety of prey, such as insects, small mollusks and crustaceans, young amphibians, worms, and frog eggs.

Image Caption: Redspotted newt or eastern newt (Notophthalmus viridescens) is a common salamander of eastern North America. Credit: Brian Gratwicke/Wikipedia (CC BY 2.0)

Eastern Newt Notophthalamus viridescens