Down in The Bottomlands by L. Sprague de Camp, Harry Turtledove

obviously out of place on donkeyback than he had yesterday. As the group rode away from the lodge, Radnal looked back and saw park militiamen and Eyes and Ears advancing on the stables to go over them again.
    He made himself forget the murder investigation and remember he was a tour guide. "Because we're off earlier this morning, we're more likely to see small reptiles and mammals that shelter against the worst heat," he said. "Many of them—"
    A sudden little flip of sandy dirt a few cubits ahead made him stop. "By the gods, there's one now." He dismounted. "I think that's a shoveler skink."
    "A what?" By now, Radnal was used to the chorus that followed whenever he pointed out one of the more unusual denizens of the Bottomlands.
    "A shoveler skink," he repeated. He crouched down. Yes, sure enough, there was the lure. He knew he had an even-money chance. If he grabbed the tail end, the lizard would shed the appendage and flee. But if he got it by the neck—
    He did. The skink twisted like a piece of demented rubber, trying to wriggle free. It also voided. Lofosa made a disgusted noise. Radnal took such things in stride.
    After thirty or forty heartbeats, the skink gave up and lay still. Radnal had been waiting for that. He carried the palm-sized lizard into the midst of the tourists. "Skinks are common all over the world, but the shoveler is the most curious variety. It's a terrestrial equivalent of the anglerfish. Look—"
    He tapped the orange fleshy lump that grew on the end of a spine about two digits long. "The skink buries itself under sand, with just this lure and the tip of its nose sticking out. See how its ribs extend to either side, so it looks more like a gliding animal than one that lives underground? It has specialized musculature, to make those long rib ends bend what we'd think of as the wrong way. When an insect comes along, the lizard tosses dirt on it, then twists around and snaps it up. It's a beautiful creature."
    "It's the ugliest thing I ever saw," Moblay Sopsirk's son declared.
    The lizard didn't care one way or the other. It peered at him through little beady black eyes. If the variety survived another few million years—if the Bottomlands survived another couple of moons, Radnal thought nervously—future specimens might lose their sight altogether, as had already happened with other subterranean skinks.
    Radnal walked out of the path, put the lizard back on the ground. It scurried away, surprisingly fast on its short legs. After six or eight cubits, it seemed to melt into the ground. Within moments, only the bright orange lure betrayed its presence.
    Evillia asked, "Do any bigger creatures go around looking for lures to catch the skinks?"
    "As a matter of fact, yes," Radnal said. "Koprit birds can see color; you'll often see shoveler skinks impaled in their hoards. Big-eared nightfoxes eat them, too, but they track by scent, not sight."
    "I hope no koprit birds come after me," Evillia said, laughing. She and Lofosa wore matching red-orange tunics—almost the same shade as the shoveler skink's lure—with two rows of big gold buttons, and red plastic necklaces with gold clasps.
    Radnal smiled. "I think you're safe enough. And now that the lizard is safe, for the time being, shall we go—? No, wait, where's freeman vez Maprab?"
    The old Strongbrow emerged from behind a big, wide-spreading thornbush a few heartbeats later, still refastening the belt to his robe. "Sorry for the delay, but I thought I'd answer nature's call while we paused here."
    "I just didn't want to lose you, freeman." Radnal stared at Benter as he got back onto his donkey. This was the first apology he'd heard from him. He wondered if the tourist was well.
    The group rode slowly eastward. Before long, people began to complain. "Every piece of Trench Park looks like every other piece," Lofosa said.
    "Yes, when will we see something different?" Moblay Sopsirk's son agreed. Radnal suspected he would have agreed if Lofosa said the