Types of fer-de-lances

Xenodon is a genus of New World snakes traditionally placed in the broad family Colubridae and, in modern classification, in the dipsadid lineage of that group. The genus holds roughly a dozen species, with 12 represented in our database. Familiar members include Wagler's Snake, Neuwied's False Fer-de-lance, the False Fer-de-lance, and the South American Hognose Snake. The names hint at the central theme of the genus, which is mimicry: several species look and act like the dangerous pit vipers they share their habitat with.

These snakes are found across Central and South America, ranging through tropical and subtropical regions from southern Central America down into Argentina. They favor warm lowland habitats including forest edges, savanna, grassland, and open scrub, and they are mostly ground-dwelling. Many species are active by day, hunting across leaf litter and soil rather than climbing.

Xenodon are recognizable as thick-bodied, moderately sized snakes, generally under a meter, with broad heads and often bold blotched or banded patterns in browns, grays, and reddish tones. Some species carry an upturned snout used for digging, which is where the hognose name comes from. The viper-like patterning of the false fer-de-lance species is a defensive resemblance, not a sign that they are pit vipers.

On venom and safety, Xenodon are rear-fanged, meaning they have enlarged grooved teeth toward the back of the upper jaw and produce a mild saliva-borne toxin used to subdue prey rather than a potent front-fanged venom. They are not considered dangerous to people and bites from them are rare and minor, but this is still a wild animal and the right response is to leave it alone. Their main defense is theater: they flatten the head and neck, hiss, strike with a closed mouth, and may play dead, all to imitate a venomous snake. Do not handle a wild snake you cannot confidently identify, and if anyone is bitten by a snake and the species or reaction is uncertain, contact emergency services or US Poison Control at 1-800-222-1222.

Ecologically, Xenodon are best known as toad and frog specialists. Several species feed heavily on toads, including toxic ones, and possess enlarged rear teeth and adaptations thought to help deflate and handle puffed-up, poison-laden prey. They reproduce by laying eggs, and beyond their feeding and bluffing behavior they live fairly secretive ground-level lives, which is part of why much of the genus remains modestly studied.