Adaptive features, such as the presence of a fan-like wettable mucro, allow some species to move at the surface of water ( " Sminthurides aquaticus ", " Sminthurides malmgreni " ) . " Podura aquatica ", a unique representative of the family Poduridae ( and one of the first springtails to have been described by Linnaeus ), spends its entire life at the surface of water, its wettable eggs dropping in water until the non-wettable first instar hatches then surfaces.
