uropod
uropod — noun
1. one of a pair of flat, wide body parts on the last section of the tail of a crus
one of a pair of flat, wide body parts on the last section of the tail of a crustacean (such as a shrimp, lobster, or crayfish). Together with the central tail piece (the telson), the uropods form a fan-like structure that helps the animal swim backward quickly and steer through the water.
To escape danger, a crayfish curls its tail and uses its uropods to swim backward.
uropods + tail curl for backward escape swimming
Marine biologists identify lobster species by the shape and color of their uropods.
shape and color of uropods for species identification
The shrimp's wide, flat uropods help push it through the water with each tail flick.
After molting, a crab's new uropods are soft and take several days to harden.
To flee predators, a prawn spreads its uropods like a fan and snaps its tail.
文法句型
uropods (plural) + verb
用法筆記
Always found in pairs (left and right). Together with the telson at the centre, the uropods make up the tail fan, which is the main swimming organ of decapod crustaceans. The uropods of each pair are slightly different in shape — the outer one (exopod) is usually larger and divided into two parts, while the inner one (endopod) is smaller and simpler.