Viruses? The viral capsid is basically just a delivery device; the payload is the RNA or DNA inside (and in most species some protein machinery to handle, e.g., integration). An empty capsid is worthless, but the RNA/DNA can make new capsids once it’s in a host cell. Sperm, as mentioned, are in a similar category; the exterior bits are the delivery system, the only part that makes it into the embryo is the DNA and its associated protein scaffold.
For something multicellular, there’s a large variety of jellyfish where sexual reproduction results in a completely different-looking, non-reproductive larva that eventually settles down and buds off clonal baby jellyfish that grow up to become sexually reproductive adults. Kind of like your facehugger example?
The larval form eventually dies after budding a certain number of times, although in some species the adult jellyfish can convert back to the larval form and repeat the cycle indefinitely without going through a sexual reproduction step.