Tiger Salamander (Ambystoma tigrinum)

DESCRIPTION: up to 6.5" in adult form and twice that in neotenic form (mature individuals that have retained the larval form -- often used as bait and called water dogs). Color variable. Has a wide snout, making the eyes appear smallish. Front and hind legs have tubercles underneath.
NATURAL HISTORY: Neoteny, becoming mature while remaining in the larval form, is common here. If the larval form metamorphoses to adult form (shown here), the adults spend much of their time in burrows dug by other animals, venturing out briefly to feed and breed after rains.