dwarf male

crustacean

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June 25, 2026

Quick Summary

In some crustacean species, males are significantly smaller than females, a phenomenon known as dwarf males. These dwarf males can be so small they are difficult to locate on the much larger females. In certain groups, such as some barnacles, these dwarf males attach themselves inside the female's mantle cavity to fertilize her eggs. This extreme difference in size between sexes is a form of sexual dimorphism.1

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cirripede
Reproduction and life cycles
…attaching to it becomes a “dwarf” male. When the male occupies a fairly exposed position on its partner, it resembles the juvenile and is capable of feeding. When, through coevolution, males have come to be protected by the partner in one way or another, the dwarf male is variously reduced,…
Read More
…attaching to it becomes a “dwarf” male. When the male occupies a fairly exposed position on its partner, it resembles the juvenile and is capable of feeding. When, through coevolution, males have come to be protected by the partner in one way or another, the dwarf male is variously reduced,…
Read More