Iguanodectes is a genus of slender, elongated tetras in the characin family, native to river and stream systems across northern and western South America, from the Amazon and Orinoco basins into Guyana, Venezuela, Colombia, Ecuador, Peru, and Bolivia. Its species share a torpedo-shaped body and a bold lengthwise stripe running from snout to tail, usually in green, gold, or bronze tones, and swim actively in loose midwater schools through both blackwater and clearwater tributaries. The genus name is generally explained as a reference to teeth resembling those of an iguana. Atlas species range from roughly 2–4 in.
In the hobby, Iguanodectes species are traded as "lizard tetras," valued for fast, active schooling behaviour and an understated but striking lateral stripe, seen well in fish such as the red-line lizard tetra (I. geisleri) and the green line tetra (I. spilurus). They do best in soft, acidic, well-oxygenated water with some current, echoing their native forest-stream habitat, and are generally peaceful additions to larger community or South American biotope tanks. Conservation status leans strongly toward Least Concern across the genus, with a single species Data Deficient, suggesting these fish are not currently considered at particular risk.