Venomous or harmless?

Pairs that people mix up most, with photos side by side, the one mark that separates them and where each one lives.

• Brown Recluse vs Wolf SpiderBrown recluse vs Wolf spider
• Coral Snake vs King SnakeEastern coral snake vs Scarlet kingsnake
• Copperhead vs CottonmouthCopperhead vs Cottonmouth
• Cottonmouth vs Water SnakeCottonmouth vs Water snake
• Coral Snake vs Milk SnakeEastern coral snake vs Milk snake
• Black Widow vs False WidowBlack widow vs False widow
• Black Widow vs Brown WidowBlack widow vs Brown widow
• Brown Recluse vs Hobo SpiderBrown recluse vs Hobo spider
• Copperhead vs Northern Water SnakeCopperhead vs Northern water snake
• Cottonmouth vs Banded Water SnakeCottonmouth vs Banded water snake
• Copperhead vs Corn SnakeCopperhead vs Corn snake
• Copperhead vs Rat SnakeCopperhead vs Rat snake
• Brown Recluse vs Cellar SpiderBrown recluse vs Cellar spider
• Hobo Spider vs Wolf SpiderHobo spider vs Wolf spider
• Copperhead vs Milk SnakeCopperhead vs Milk snake
• Brown Recluse vs Southern House SpiderBrown recluse vs Southern house spider
• Rattlesnake vs Gopher SnakeWestern rattlesnake vs Gopher snake
• Cottonmouth vs Diamondback Water SnakeCottonmouth vs Diamondback water snake
• Eastern Diamondback vs Timber RattlesnakeEastern diamondback rattlesnake vs Timber rattlesnake
• Cottonmouth vs Brown Water SnakeCottonmouth vs Brown water snake
• Coral Snake vs Scarlet SnakeEastern coral snake vs Scarlet snake
• Timber Rattlesnake vs CopperheadTimber rattlesnake vs Copperhead
• Western Diamondback vs Mojave RattlesnakeWestern diamondback rattlesnake vs Mojave rattlesnake
• Pygmy Rattlesnake vs Hognose SnakePygmy rattlesnake vs Eastern hognose snake
• Copperhead vs Hognose SnakeCopperhead vs Eastern hognose snake
• Bark Scorpion vs Desert Hairy ScorpionArizona bark scorpion vs Giant desert hairy scorpion