The species is the only known modern frog species with lower teeth, though certain other species with upper teeth do have toothlike structures on the lower jaw.

这是现代青蛙中唯一一种已知下颌长牙的蛙类物种，虽然其他上颌长牙的蛙类在下颌肯定也有类牙构造。

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This allows the crab to insert a large toothlike appendage on its right-hand claw into the opening, thus cracking the snail's shell.

ECONOMIST: Why some snails are left-handed