A western diamondback rattlesnake - a venomous reptile with a deadly bite - was photographed lurking in an Arizona backyard, but it was camouflaged so well that some studying the image struggled to spot it.
Rattlesnake Solutions - a snake removal and rattlesnake control service based in Phoenix and Tucson - posted a picture on Facebook of a rocky slope and asked followers whether they could find the serpent in the scene.
'I still don't see it,' Phillip Floyd said after examining the image. 'Somebody show me.'
The spot-the-snake challenge highlights how easy it can be to unknowingly cross paths with the dangerous creature, which some experts say is responsible for the most snake fatalities in the nation.
Arizona-based Rattlesnake Solutions posted a picture on Facebook of a rocky hill and asked followers whether they could spot the serpent in the scene.
'The Western Diamondback Rattlesnake is notorious for its fatal bite, and has instilled a certain fear and paranoia in humans,' according the University of Michigan's School of Zoology.
The species might strike a person if it feels threatened, but generally prefers small mammals, birds, fish and other reptiles, the school said.
'In a matter of seconds, individuals of this species can leave a fatal bite by injecting venom into its prey.'
If you look closely, you can see the snake hiding beneath the rock, obscured by a shadow
Some eagle-eyed followers spotted the coiled-up serpent hiding beneath a rock, where a shadow helped obscure its presence.
'I saw it right away and if I saw it in real life if I had a yard I'd just go about my