On some tropical reefs , several species of minute Synalpheus pistol shrimp that depend on certain sponges for the survival of their colony , live eusocially , with a single breeding female and a preponderance of male defenders , armed with enlarged snapping claws . On some tropical reefs several species of minute Synalpheus pistol shrimp , that depend on certain sponges for the survival of their colony , live eusocially with a single breeding female and a preponderance of male defenders , armed with enlarged snapping claws .