I've caught and kept these shrimps in a tropical freshwater tank but as they are small/delicate get killed within a few weeks by anything bigger than a guppy. Only ever survived long term in a guppy/neon/danio tank.
research from google says Paratya curvirostris exist on pacific rim lands formed from the break up of Gondwana. they basically have the same life cycle as white bait hence why you'll find them on coastal streams. Doc may not be happy them been sold on trademe.